From eb6816a823da7ba144659eb6b2c5ea823558982b Mon Sep 17 00:00:00 2001
From: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
Date: Wed, 3 Sep 2025 14:50:43 +0200
Subject: [PATCH 01/14] Add mcap support for osi3trace

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
---
 osi3trace/osi_trace.py | 182 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 178 insertions(+), 4 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index 3c05770..d4ae5f2 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -3,8 +3,14 @@
 """
 
 import lzma
+from pathlib import Path
 import struct
 
+from abc import ABC, abstractmethod
+
+from mcap_protobuf.decoder import DecoderFactory
+from mcap.reader import make_reader
+
 from osi3.osi_sensorview_pb2 import SensorView
 from osi3.osi_sensorviewconfiguration_pb2 import SensorViewConfiguration
 from osi3.osi_groundtruth_pb2 import GroundTruth
@@ -32,8 +38,8 @@
 
 
 class OSITrace:
-    """This class can import and decode OSI trace files."""
-
+    """This class can import and decode OSI single- and multi-channel trace files."""
+    
     @staticmethod
     def map_message_type(type_name):
         """Map the type name to the protobuf message type."""
@@ -43,9 +49,120 @@ def map_message_type(type_name):
     def message_types():
         """Message types that OSITrace supports."""
         return list(MESSAGES_TYPE.keys())
+    
+    def __init__(self, path=None, type_name="SensorView", cache_messages=False, topic=None):
+        """
+        Initializes the trace reader depending on the trace file format.
+        
+        Args:
+            path (str): The path to the trace file.
+            type_name (str): The type name of the messages in the trace; check supported message types with `OSITrace.message_types()`.
+            cache_messages (bool): Whether to cache messages in memory (only applies to single-channel traces).
+            topic (str): The topic name for multi-channel traces (only applies to multi-channel traces); Using the first available topic if not specified.
+        """
+        self.reader = None
+        self.path = None
+
+        if path is not None:
+            self.reader = self._init_reader(Path(path), type_name, cache_messages, topic)
+            
+    def _init_reader(self, path, type_name, cache_messages, topic):
+        if not path.exists():
+            raise FileNotFoundError("File not found")
+
+        if path.suffix.lower() == ".mcap":
+            reader = OSITraceMulti(path, topic)
+            if reader.get_message_type() != type_name:
+                raise ValueError(f"Channel message type '{reader.get_message_type()}' does not match expected type '{type_name}'")
+            return reader
+        elif path.suffix.lower() in [".osi", ".lzma", ".xz"]:
+            return OSITraceSingle(str(path), type_name, cache_messages)
+        else:
+            raise ValueError(f"Unsupported file format: '{path.suffix}'")
+
+    def from_file(self, path, type_name="SensorView", cache_messages=False, topic=None):
+        """
+        Initializes the trace reader depending on the trace file format.
+        
+        Args:
+            path (str): The path to the trace file.
+            type_name (str): The type name of the messages in the trace; check supported message types with `OSITrace.message_types()`.
+            cache_messages (bool): Whether to cache messages in memory (only applies to single-channel traces).
+            topic (str): The topic name for multi-channel traces (only applies to multi-channel traces); Using the first available topic if not specified.
+        """
+        self.reader = self._init_reader(Path(path), type_name, cache_messages, topic)
+
+    def restart(self, index=None):
+        """
+        Restart the trace reader.
+
+        Note:
+            Multi-channel traces don't support restarting from a specific index.
+        """
+        return self.reader.restart(index)
+
+    def __iter__(self):
+        return self.reader.__iter__()
+
+    def close(self):
+        return self.reader.close()
+
+    def retrieve_offsets(self, limit=None):
+        if isinstance(self.reader, OSITraceSingle):
+            return self.reader.retrieve_offsets(limit)
+        raise NotImplementedError("Offsets are only supported for single-channel traces.")
+
+    def retrieve_message(self, index=None, skip=False):
+        if isinstance(self.reader, OSITraceSingle):
+            return self.reader.retrieve_message(index, skip)
+        raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
+
+    def get_message_by_index(self, index):
+        if isinstance(self.reader, OSITraceSingle):
+            return self.reader.get_message_by_index(index)
+        raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
+
+    def get_messages_in_index_range(self, begin, end):
+        if isinstance(self.reader, OSITraceSingle):
+            return self.reader.get_messages_in_index_range(begin, end)
+        raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
+
+    def get_available_topics(self):
+        if isinstance(self.reader, OSITraceMulti):
+            return self.reader.get_available_topics()
+        raise NotImplementedError("Getting available topics is only supported for multi-channel traces.")
+    
+    def get_file_metadata(self):
+        if isinstance(self.reader, OSITraceMulti):
+            return self.reader.get_file_metadata()
+        raise NotImplementedError("Getting file metadata is only supported for multi-channel traces.")
+    
+    def get_channel_metadata(self):
+        if isinstance(self.reader, OSITraceMulti):
+            return self.reader.get_channel_metadata()
+        raise NotImplementedError("Getting channel metadata is only supported for multi-channel traces.")
+
+
+class ReaderBase(ABC):
+    """Common interface for trace readers"""
+    @abstractmethod
+    def restart(self, index=None):
+        pass
+    
+    @abstractmethod
+    def __iter__(self):
+        pass
+
+    @abstractmethod
+    def close(self):
+        pass
 
+
+class OSITraceSingle(ReaderBase):
+    """OSI single-channel trace reader"""
+    
     def __init__(self, path=None, type_name="SensorView", cache_messages=False):
-        self.type = self.map_message_type(type_name)
+        self.type = OSITrace.map_message_type(type_name)
         self.file = None
         self.current_index = None
         self.message_offsets = None
@@ -57,7 +174,7 @@ def __init__(self, path=None, type_name="SensorView", cache_messages=False):
 
     def from_file(self, path, type_name="SensorView", cache_messages=False):
         """Import a trace from a file"""
-        self.type = self.map_message_type(type_name)
+        self.type = OSITrace.map_message_type(type_name)
 
         if path.lower().endswith((".lzma", ".xz")):
             self.file = lzma.open(path, "rb")
@@ -186,3 +303,60 @@ def close(self):
         self.read_complete = False
         self.read_limit = None
         self.type = None
+
+
+class OSITraceMulti(ReaderBase):
+    """OSI multi-channel trace reader"""
+
+    def __init__(self, path, topic):
+        self.path = Path(path)
+        self._file = open(self.path, "rb")
+        self.mcap_reader = make_reader(self._file, decoder_factories=[DecoderFactory()])
+        self._summary = self.mcap_reader.get_summary()
+        available_topics = self.get_available_topics()
+        if topic == None:
+            topic = available_topics[0]
+        if topic not in available_topics:
+            raise ValueError(f"The requested topic '{topic}' is not present in the trace file.")
+        self.topic = topic
+    
+    def restart(self, index=None):
+        if index != None:
+            raise NotImplementedError("Restarting from a given index is not supported for multi-channel traces.")
+        if hasattr(self, "_iter"):
+            del self._iter
+
+    def __iter__(self):
+        """Stateful iterator over the channel's messages in log time order."""
+        if not hasattr(self, "_iter"):
+            self._iter = self.mcap_reader.iter_decoded_messages(topics=[self.topic])
+        for message in self._iter:
+            yield message.decoded_message
+    
+    def close(self):
+        self._file.close()
+
+    def get_available_topics(self):
+        return [channel.topic for id, channel in self._summary.channels.items()]
+
+    def get_file_metadata(self):
+        metadata = []
+        for metadata_entry in self.mcap_reader.iter_metadata():
+            metadata.append(metadata_entry)
+        return metadata
+
+    def get_channel_metadata(self):
+        for id, channel in self._summary.channels.items():
+            if channel.topic == self.topic:
+                return channel.metadata
+        return None
+    
+    def get_message_type(self):
+        for channel_id, channel in self._summary.channels.items():
+            if channel.topic == self.topic:
+                schema = self._summary.schemas[channel.schema_id]
+                if schema.name.startswith("osi3."):
+                    return schema.name[len("osi3.") :]
+                else:
+                    raise ValueError(f"Schema '{schema.name}' is not an 'osi3.' schema.")
+        return None

From adc1cadc0bd81fa3c04236503504cb84d6ba011a Mon Sep 17 00:00:00 2001
From: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
Date: Thu, 4 Sep 2025 10:30:29 +0200
Subject: [PATCH 02/14] Update mcap dependencies

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
---
 poetry.lock    | 202 ++++++++++++++++++++++++++++++++++++++++++++++++-
 pyproject.toml |   2 +
 2 files changed, 203 insertions(+), 1 deletion(-)

diff --git a/poetry.lock b/poetry.lock
index 822e999..cef8a9d 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -106,6 +106,94 @@ files = [
     {file = "iniconfig-2.1.0.tar.gz", hash = "sha256:3abbd2e30b36733fee78f9c7f7308f2d0050e88f0087fd25c2645f63c773e1c7"},
 ]
 
+[[package]]
+name = "lz4"
+version = "4.4.4"
+description = "LZ4 Bindings for Python"
+optional = false
+python-versions = ">=3.9"
+groups = ["main"]
+files = [
+    {file = "lz4-4.4.4-cp310-cp310-macosx_10_9_x86_64.whl", hash = "sha256:f170abb8416c4efca48e76cac2c86c3185efdf841aecbe5c190121c42828ced0"},
+    {file = "lz4-4.4.4-cp310-cp310-macosx_11_0_arm64.whl", hash = "sha256:d33a5105cd96ebd32c3e78d7ece6123a9d2fb7c18b84dec61f27837d9e0c496c"},
+    {file = "lz4-4.4.4-cp310-cp310-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:30ebbc5b76b4f0018988825a7e9ce153be4f0d4eba34e6c1f2fcded120573e88"},
+    {file = "lz4-4.4.4-cp310-cp310-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:dc64d6dfa7a89397529b22638939e70d85eaedc1bd68e30a29c78bfb65d4f715"},
+    {file = "lz4-4.4.4-cp310-cp310-manylinux_2_5_i686.manylinux1_i686.manylinux_2_17_i686.manylinux2014_i686.whl", hash = "sha256:a355223a284f42a723c120ce68827de66d5cb872a38732b3d5abbf544fa2fe26"},
+    {file = "lz4-4.4.4-cp310-cp310-win32.whl", hash = "sha256:b28228197775b7b5096898851d59ef43ccaf151136f81d9c436bc9ba560bc2ba"},
+    {file = "lz4-4.4.4-cp310-cp310-win_amd64.whl", hash = "sha256:45e7c954546de4f85d895aa735989d77f87dd649f503ce1c8a71a151b092ed36"},
+    {file = "lz4-4.4.4-cp310-cp310-win_arm64.whl", hash = "sha256:e3fc90f766401684740978cd781d73b9685bd81b5dbf7257542ef9de4612e4d2"},
+    {file = "lz4-4.4.4-cp311-cp311-macosx_10_9_x86_64.whl", hash = "sha256:ddfc7194cd206496c445e9e5b0c47f970ce982c725c87bd22de028884125b68f"},
+    {file = "lz4-4.4.4-cp311-cp311-macosx_11_0_arm64.whl", hash = "sha256:714f9298c86f8e7278f1c6af23e509044782fa8220eb0260f8f8f1632f820550"},
+    {file = "lz4-4.4.4-cp311-cp311-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:a8474c91de47733856c6686df3c4aca33753741da7e757979369c2c0d32918ba"},
+    {file = "lz4-4.4.4-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:80dd27d7d680ea02c261c226acf1d41de2fd77af4fb2da62b278a9376e380de0"},
+    {file = "lz4-4.4.4-cp311-cp311-manylinux_2_5_i686.manylinux1_i686.manylinux_2_17_i686.manylinux2014_i686.whl", hash = "sha256:9b7d6dddfd01b49aedb940fdcaf32f41dc58c926ba35f4e31866aeec2f32f4f4"},
+    {file = "lz4-4.4.4-cp311-cp311-win32.whl", hash = "sha256:4134b9fd70ac41954c080b772816bb1afe0c8354ee993015a83430031d686a4c"},
+    {file = "lz4-4.4.4-cp311-cp311-win_amd64.whl", hash = "sha256:f5024d3ca2383470f7c4ef4d0ed8eabad0b22b23eeefde1c192cf1a38d5e9f78"},
+    {file = "lz4-4.4.4-cp311-cp311-win_arm64.whl", hash = "sha256:6ea715bb3357ea1665f77874cf8f55385ff112553db06f3742d3cdcec08633f7"},
+    {file = "lz4-4.4.4-cp312-cp312-macosx_10_13_x86_64.whl", hash = "sha256:23ae267494fdd80f0d2a131beff890cf857f1b812ee72dbb96c3204aab725553"},
+    {file = "lz4-4.4.4-cp312-cp312-macosx_11_0_arm64.whl", hash = "sha256:fff9f3a1ed63d45cb6514bfb8293005dc4141341ce3500abdfeb76124c0b9b2e"},
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+    {file = "lz4-4.4.4-cp39-cp39-win_amd64.whl", hash = "sha256:4ab1537bd3b3bfbafd3c8847e06827129794488304f21945fc2f5b669649d94f"},
+    {file = "lz4-4.4.4-cp39-cp39-win_arm64.whl", hash = "sha256:38730927ad51beb42ab8dbc5555270bfbe86167ba734265f88bbd799fced1004"},
+    {file = "lz4-4.4.4.tar.gz", hash = "sha256:070fd0627ec4393011251a094e08ed9fdcc78cb4e7ab28f507638eee4e39abda"},
+]
+
+[package.extras]
+docs = ["sphinx (>=1.6.0)", "sphinx_bootstrap_theme"]
+flake8 = ["flake8"]
+tests = ["psutil", "pytest (!=3.3.0)", "pytest-cov"]
+
+[[package]]
+name = "mcap"
+version = "1.3.0"
+description = "MCAP libraries for Python"
+optional = false
+python-versions = ">=3.7"
+groups = ["main"]
+files = [
+    {file = "mcap-1.3.0-py3-none-any.whl", hash = "sha256:6262a68cd5a9ed7f8fe8fa6330412a87949842782ab42a4800cd033d0f38e4cd"},
+    {file = "mcap-1.3.0.tar.gz", hash = "sha256:5f0d5826ba3b8418508c1d992bada4c5744073f1b3e6d685579f0aca0389fb2f"},
+]
+
+[package.dependencies]
+lz4 = "*"
+zstandard = "*"
+
+[[package]]
+name = "mcap-protobuf-support"
+version = "0.5.3"
+description = "Protobuf support for the Python MCAP library"
+optional = false
+python-versions = ">=3.7"
+groups = ["main"]
+files = [
+    {file = "mcap_protobuf_support-0.5.3-py3-none-any.whl", hash = "sha256:2cdfe7082f26f7da1bae8fa91c9196820562d03dccf39d4e4de11e8287f92dcb"},
+    {file = "mcap_protobuf_support-0.5.3.tar.gz", hash = "sha256:0545ed005cdc6ac22c5d87a7d8574f0e9adb0c5da7b0f46ae896f5702fc1a250"},
+]
+
+[package.dependencies]
+mcap = ">=0.0.14"
+protobuf = ">=4.25"
+
 [[package]]
 name = "mypy-extensions"
 version = "1.1.0"
@@ -289,7 +377,119 @@ files = [
     {file = "typing_extensions-4.14.1.tar.gz", hash = "sha256:38b39f4aeeab64884ce9f74c94263ef78f3c22467c8724005483154c26648d36"},
 ]
 
+[[package]]
+name = "zstandard"
+version = "0.24.0"
+description = "Zstandard bindings for Python"
+optional = false
+python-versions = ">=3.9"
+groups = ["main"]
+files = [
+    {file = "zstandard-0.24.0-cp310-cp310-macosx_10_9_x86_64.whl", hash = "sha256:af1394c2c5febc44e0bbf0fc6428263fa928b50d1b1982ce1d870dc793a8e5f4"},
+    {file = "zstandard-0.24.0-cp310-cp310-macosx_11_0_arm64.whl", hash = "sha256:5e941654cef13a1d53634ec30933722eda11f44f99e1d0bc62bbce3387580d50"},
+    {file = "zstandard-0.24.0-cp310-cp310-manylinux2010_i686.manylinux2014_i686.manylinux_2_12_i686.manylinux_2_17_i686.whl", hash = "sha256:561123d05681197c0e24eb8ab3cfdaf299e2b59c293d19dad96e1610ccd8fbc6"},
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+    {file = "zstandard-0.24.0.tar.gz", hash = "sha256:fe3198b81c00032326342d973e526803f183f97aa9e9a98e3f897ebafe21178f"},
+]
+
+[package.extras]
+cffi = ["cffi (>=1.17) ; python_version >= \"3.13\" and platform_python_implementation != \"PyPy\""]
+
 [metadata]
 lock-version = "2.1"
 python-versions = ">=3.10"
-content-hash = "f3992efe3ec9125cff08fa51b4e4b2f1281385b4fe5c5ca40cb3206ec192aeeb"
+content-hash = "d8d891dd9c0a16ba9080b4960ccdd5dd1048f27d04f1026e221132d9023df1ab"
diff --git a/pyproject.toml b/pyproject.toml
index 7292f6f..76108b3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,6 +13,8 @@ dynamic = ["version"]
 requires-python = ">=3.10"
 dependencies = [
     "protobuf>=6.30.2",
+    "mcap>=1.2.2",
+    "mcap-protobuf-support>=0.5.3"
 ]
 
 [project.urls]

From c42364442b71e3291d3bc522454289dc5ad3c0c4 Mon Sep 17 00:00:00 2001
From: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
Date: Thu, 4 Sep 2025 15:45:42 +0200
Subject: [PATCH 03/14] Minor changes

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
---
 osi3trace/osi_trace.py | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index d4ae5f2..00ae426 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -312,6 +312,7 @@ def __init__(self, path, topic):
         self.path = Path(path)
         self._file = open(self.path, "rb")
         self.mcap_reader = make_reader(self._file, decoder_factories=[DecoderFactory()])
+        self._iter = None
         self._summary = self.mcap_reader.get_summary()
         available_topics = self.get_available_topics()
         if topic == None:
@@ -323,18 +324,22 @@ def __init__(self, path, topic):
     def restart(self, index=None):
         if index != None:
             raise NotImplementedError("Restarting from a given index is not supported for multi-channel traces.")
-        if hasattr(self, "_iter"):
-            del self._iter
+        self._iter = None
 
     def __iter__(self):
         """Stateful iterator over the channel's messages in log time order."""
-        if not hasattr(self, "_iter"):
+        if self._iter is None:
             self._iter = self.mcap_reader.iter_decoded_messages(topics=[self.topic])
         for message in self._iter:
             yield message.decoded_message
     
     def close(self):
-        self._file.close()
+        if self._file:
+            self._file.close()
+        self._file = None
+        self.mcap_reader = None
+        self._summary = None
+        self._iter = None
 
     def get_available_topics(self):
         return [channel.topic for id, channel in self._summary.channels.items()]

From 635b227d956bb4711bf1823f67a1a934ff46655f Mon Sep 17 00:00:00 2001
From: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
Date: Wed, 24 Sep 2025 10:43:21 +0200
Subject: [PATCH 04/14] Minor attribute protection changes

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
---
 osi3trace/osi_trace.py | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index 00ae426..56a1a74 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -61,7 +61,6 @@ def __init__(self, path=None, type_name="SensorView", cache_messages=False, topi
             topic (str): The topic name for multi-channel traces (only applies to multi-channel traces); Using the first available topic if not specified.
         """
         self.reader = None
-        self.path = None
 
         if path is not None:
             self.reader = self._init_reader(Path(path), type_name, cache_messages, topic)
@@ -145,6 +144,7 @@ def get_channel_metadata(self):
 
 class ReaderBase(ABC):
     """Common interface for trace readers"""
+    
     @abstractmethod
     def restart(self, index=None):
         pass
@@ -309,11 +309,10 @@ class OSITraceMulti(ReaderBase):
     """OSI multi-channel trace reader"""
 
     def __init__(self, path, topic):
-        self.path = Path(path)
-        self._file = open(self.path, "rb")
-        self.mcap_reader = make_reader(self._file, decoder_factories=[DecoderFactory()])
+        self._file = open(path, "rb")
+        self._mcap_reader = make_reader(self._file, decoder_factories=[DecoderFactory()])
         self._iter = None
-        self._summary = self.mcap_reader.get_summary()
+        self._summary = self._mcap_reader.get_summary()
         available_topics = self.get_available_topics()
         if topic == None:
             topic = available_topics[0]
@@ -329,7 +328,7 @@ def restart(self, index=None):
     def __iter__(self):
         """Stateful iterator over the channel's messages in log time order."""
         if self._iter is None:
-            self._iter = self.mcap_reader.iter_decoded_messages(topics=[self.topic])
+            self._iter = self._mcap_reader.iter_decoded_messages(topics=[self.topic])
         for message in self._iter:
             yield message.decoded_message
     
@@ -337,7 +336,7 @@ def close(self):
         if self._file:
             self._file.close()
         self._file = None
-        self.mcap_reader = None
+        self._mcap_reader = None
         self._summary = None
         self._iter = None
 
@@ -346,7 +345,7 @@ def get_available_topics(self):
 
     def get_file_metadata(self):
         metadata = []
-        for metadata_entry in self.mcap_reader.iter_metadata():
+        for metadata_entry in self._mcap_reader.iter_metadata():
             metadata.append(metadata_entry)
         return metadata
 

From 16abb2c928e20283a28e03f822a3047e76a821dc Mon Sep 17 00:00:00 2001
From: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
Date: Wed, 24 Sep 2025 11:16:20 +0200
Subject: [PATCH 05/14] Delegate legacy instance attributes

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
---
 osi3trace/osi_trace.py | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index 56a1a74..480f145 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -50,6 +50,42 @@ def message_types():
         """Message types that OSITrace supports."""
         return list(MESSAGES_TYPE.keys())
     
+    _legacy_ositrace_attributes = {
+        "type",
+        "file",
+        "current_index",
+        "message_offsets",
+        "read_complete",
+        "message_cache",
+    }
+
+    def __getattr__(self, name):
+        """
+        This method forwards the getattr call for unsuccessful legacy attribute
+        name lookups to the reader in case it is an OSITraceSingle instance.
+        """
+        if name in self._legacy_ositrace_attributes and isinstance(self.reader, OSITraceSingle):
+            return getattr(self.reader, name)
+        raise AttributeError(f"'{type(self).__name__}' object has no attribute '{name}'")
+    
+    def __setattr__(self, name, value):
+        """
+        This method overwrites the default setter and forwards setattr calls for
+        legacy attribute names to the reader in case the reader is an
+        OSITraceSingle instance. Otherwise it uses the default setter.
+        """
+        reader = super().__getattribute__("reader") if "reader" in self.__dict__ else None
+        if name in self._legacy_ositrace_attributes and isinstance(reader, OSITraceSingle):
+            setattr(reader, name, value)
+        else:
+            super().__setattr__(name, value)
+
+    def __dir__(self):
+        attrs = super().__dir__()
+        if isinstance(self.reader, OSITraceSingle):
+            attrs += list(self._legacy_ositrace_attributes)
+        return attrs
+    
     def __init__(self, path=None, type_name="SensorView", cache_messages=False, topic=None):
         """
         Initializes the trace reader depending on the trace file format.

From d5b70dbb21b3074ff0313979e26c7b976572f986 Mon Sep 17 00:00:00 2001
From: "Pierre R. Mai" <pmai@pmsf.de>
Date: Tue, 21 Oct 2025 11:14:05 +0200
Subject: [PATCH 06/14] Apply refactoring to unify trace implementations more

Signed-off-by: Pierre R. Mai <pmai@pmsf.de>
---
 osi3trace/osi_trace.py | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index 480f145..f9f0d87 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -106,12 +106,9 @@ def _init_reader(self, path, type_name, cache_messages, topic):
             raise FileNotFoundError("File not found")
 
         if path.suffix.lower() == ".mcap":
-            reader = OSITraceMulti(path, topic)
-            if reader.get_message_type() != type_name:
-                raise ValueError(f"Channel message type '{reader.get_message_type()}' does not match expected type '{type_name}'")
-            return reader
+            return OSITraceMulti(path, type_name, topic)
         elif path.suffix.lower() in [".osi", ".lzma", ".xz"]:
-            return OSITraceSingle(str(path), type_name, cache_messages)
+            return OSITraceSingle(path, type_name, cache_messages)
         else:
             raise ValueError(f"Unsupported file format: '{path.suffix}'")
 
@@ -212,7 +209,7 @@ def from_file(self, path, type_name="SensorView", cache_messages=False):
         """Import a trace from a file"""
         self.type = OSITrace.map_message_type(type_name)
 
-        if path.lower().endswith((".lzma", ".xz")):
+        if path.suffix.lower() in [".lzma", ".xz"]:
             self.file = lzma.open(path, "rb")
         else:
             self.file = open(path, "rb")
@@ -344,16 +341,16 @@ def close(self):
 class OSITraceMulti(ReaderBase):
     """OSI multi-channel trace reader"""
 
-    def __init__(self, path, topic):
+    def __init__(self, path, type_name, topic):
         self._file = open(path, "rb")
         self._mcap_reader = make_reader(self._file, decoder_factories=[DecoderFactory()])
         self._iter = None
         self._summary = self._mcap_reader.get_summary()
-        available_topics = self.get_available_topics()
+        available_topics = self.get_available_topics(type_name)
         if topic == None:
-            topic = available_topics[0]
+            topic = next(iter(available_topics), None)
         if topic not in available_topics:
-            raise ValueError(f"The requested topic '{topic}' is not present in the trace file.")
+            raise ValueError(f"The requested topic '{topic}' is not present in the trace file or is not of type '{type_name}'.")
         self.topic = topic
     
     def restart(self, index=None):
@@ -376,8 +373,8 @@ def close(self):
         self._summary = None
         self._iter = None
 
-    def get_available_topics(self):
-        return [channel.topic for id, channel in self._summary.channels.items()]
+    def get_available_topics(self, type_name = None):
+        return [channel.topic for channel in self._summary.channels.values() if self._channel_is_of_type(channel, type_name)]
 
     def get_file_metadata(self):
         metadata = []
@@ -392,7 +389,7 @@ def get_channel_metadata(self):
         return None
     
     def get_message_type(self):
-        for channel_id, channel in self._summary.channels.items():
+        for channel in self._summary.channels.values():
             if channel.topic == self.topic:
                 schema = self._summary.schemas[channel.schema_id]
                 if schema.name.startswith("osi3."):
@@ -400,3 +397,7 @@ def get_message_type(self):
                 else:
                     raise ValueError(f"Schema '{schema.name}' is not an 'osi3.' schema.")
         return None
+    
+    def _channel_is_of_type(self, channel, type_name):
+        schema = self._summary.schemas[channel.schema_id]  
+        return type_name is None or schema.name == f"osi3.{type_name}"

From e45ee9cfdf117535a2d345f105cec998a9b74b30 Mon Sep 17 00:00:00 2001
From: "Pierre R. Mai" <pmai@pmsf.de>
Date: Tue, 21 Oct 2025 12:39:57 +0200
Subject: [PATCH 07/14] Deprecate single-channel only methods, unify new
 methods

Add deprecation for purely single-channel only legacy methods, place new
methods as reusable base methods, which can potentially be implemented
in the future for single-channel as well.

Signed-off-by: Pierre R. Mai <pmai@pmsf.de>
---
 osi3trace/osi_trace.py  | 65 +++++++++++++++++++++++++----------------
 poetry.lock             |  5 ++--
 pyproject.toml          |  1 +
 tests/test_osi_trace.py | 47 +++++++++++++++++++++--------
 4 files changed, 78 insertions(+), 40 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index f9f0d87..4e56370 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -7,6 +7,7 @@
 import struct
 
 from abc import ABC, abstractmethod
+from typing_extensions import deprecated
 
 from mcap_protobuf.decoder import DecoderFactory
 from mcap.reader import make_reader
@@ -139,40 +140,38 @@ def __iter__(self):
     def close(self):
         return self.reader.close()
 
+    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def retrieve_offsets(self, limit=None):
         if isinstance(self.reader, OSITraceSingle):
             return self.reader.retrieve_offsets(limit)
         raise NotImplementedError("Offsets are only supported for single-channel traces.")
 
+    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def retrieve_message(self, index=None, skip=False):
         if isinstance(self.reader, OSITraceSingle):
             return self.reader.retrieve_message(index, skip)
         raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
 
+    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def get_message_by_index(self, index):
         if isinstance(self.reader, OSITraceSingle):
             return self.reader.get_message_by_index(index)
         raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
 
+    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def get_messages_in_index_range(self, begin, end):
         if isinstance(self.reader, OSITraceSingle):
             return self.reader.get_messages_in_index_range(begin, end)
         raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
 
     def get_available_topics(self):
-        if isinstance(self.reader, OSITraceMulti):
-            return self.reader.get_available_topics()
-        raise NotImplementedError("Getting available topics is only supported for multi-channel traces.")
+        return self.reader.get_available_topics()
     
     def get_file_metadata(self):
-        if isinstance(self.reader, OSITraceMulti):
-            return self.reader.get_file_metadata()
-        raise NotImplementedError("Getting file metadata is only supported for multi-channel traces.")
+        return self.reader.get_file_metadata()
     
     def get_channel_metadata(self):
-        if isinstance(self.reader, OSITraceMulti):
-            return self.reader.get_channel_metadata()
-        raise NotImplementedError("Getting channel metadata is only supported for multi-channel traces.")
+        return self.reader.get_channel_metadata()
 
 
 class ReaderBase(ABC):
@@ -190,6 +189,18 @@ def __iter__(self):
     def close(self):
         pass
 
+    @abstractmethod
+    def get_available_topics(self):
+        pass
+
+    @abstractmethod
+    def get_file_metadata(self):
+        pass
+
+    @abstractmethod
+    def get_channel_metadata(self):
+        pass
+
 
 class OSITraceSingle(ReaderBase):
     """OSI single-channel trace reader"""
@@ -203,21 +214,16 @@ def __init__(self, path=None, type_name="SensorView", cache_messages=False):
         self.message_cache = {} if cache_messages else None
         self._header_length = 4
         if path:
-            self.from_file(path, type_name, cache_messages)
-
-    def from_file(self, path, type_name="SensorView", cache_messages=False):
-        """Import a trace from a file"""
-        self.type = OSITrace.map_message_type(type_name)
+            self.type = OSITrace.map_message_type(type_name)
 
-        if path.suffix.lower() in [".lzma", ".xz"]:
-            self.file = lzma.open(path, "rb")
-        else:
-            self.file = open(path, "rb")
-
-        self.read_complete = False
-        self.current_index = 0
-        self.message_offsets = [0]
-        self.message_cache = {} if cache_messages else None
+            if path.suffix.lower() in [".lzma", ".xz"]:
+                self.file = lzma.open(path, "rb")
+            else:
+                self.file = open(path, "rb")
+            self.read_complete = False
+            self.current_index = 0
+            self.message_offsets = [0]
+            self.message_cache = {} if cache_messages else None
 
     def retrieve_offsets(self, limit=None):
         """Retrieve the offsets of the messages from the file."""
@@ -337,6 +343,15 @@ def close(self):
         self.read_limit = None
         self.type = None
 
+    def get_available_topics(self):
+        raise NotImplementedError("Getting available topics is only supported for multi-channel traces.")
+
+    def get_file_metadata(self):
+        raise NotImplementedError("Getting file metadata is only supported for multi-channel traces.")
+
+    def get_channel_metadata(self):
+        raise NotImplementedError("Getting channel metadata is only supported for multi-channel traces.")
+
 
 class OSITraceMulti(ReaderBase):
     """OSI multi-channel trace reader"""
@@ -387,7 +402,7 @@ def get_channel_metadata(self):
             if channel.topic == self.topic:
                 return channel.metadata
         return None
-    
+
     def get_message_type(self):
         for channel in self._summary.channels.values():
             if channel.topic == self.topic:
@@ -397,7 +412,7 @@ def get_message_type(self):
                 else:
                     raise ValueError(f"Schema '{schema.name}' is not an 'osi3.' schema.")
         return None
-    
+
     def _channel_is_of_type(self, channel, type_name):
         schema = self._summary.schemas[channel.schema_id]  
         return type_name is None or schema.name == f"osi3.{type_name}"
diff --git a/poetry.lock b/poetry.lock
index cef8a9d..e135a32 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -370,8 +370,7 @@ version = "4.14.1"
 description = "Backported and Experimental Type Hints for Python 3.9+"
 optional = false
 python-versions = ">=3.9"
-groups = ["dev"]
-markers = "python_version == \"3.10\""
+groups = ["main", "dev"]
 files = [
     {file = "typing_extensions-4.14.1-py3-none-any.whl", hash = "sha256:d1e1e3b58374dc93031d6eda2420a48ea44a36c2b4766a4fdeb3710755731d76"},
     {file = "typing_extensions-4.14.1.tar.gz", hash = "sha256:38b39f4aeeab64884ce9f74c94263ef78f3c22467c8724005483154c26648d36"},
@@ -492,4 +491,4 @@ cffi = ["cffi (>=1.17) ; python_version >= \"3.13\" and platform_python_implemen
 [metadata]
 lock-version = "2.1"
 python-versions = ">=3.10"
-content-hash = "d8d891dd9c0a16ba9080b4960ccdd5dd1048f27d04f1026e221132d9023df1ab"
+content-hash = "2fb49d217c020e5dacb4a9ccbd6e9e833deaf265dc7279ef98ad6106dcf90d95"
diff --git a/pyproject.toml b/pyproject.toml
index 76108b3..211cd1b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -12,6 +12,7 @@ readme = "README.md"
 dynamic = ["version"]
 requires-python = ">=3.10"
 dependencies = [
+    "typing-extensions~=4.9",
     "protobuf>=6.30.2",
     "mcap>=1.2.2",
     "mcap-protobuf-support>=0.5.3"
diff --git a/tests/test_osi_trace.py b/tests/test_osi_trace.py
index 9d74f5a..c508cde 100644
--- a/tests/test_osi_trace.py
+++ b/tests/test_osi_trace.py
@@ -1,6 +1,7 @@
 import os
 import tempfile
 import unittest
+import warnings
 
 from osi3trace.osi_trace import OSITrace
 from osi3.osi_sensorview_pb2 import SensorView
@@ -30,7 +31,9 @@ def test_osi_trace_sv(self):
                     self.assertIsInstance(message, SensorView)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -47,7 +50,9 @@ def test_osi_trace_svc(self):
                     self.assertIsInstance(message, SensorViewConfiguration)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 1)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 1)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -64,7 +69,9 @@ def test_osi_trace_gt(self):
                     self.assertIsInstance(message, GroundTruth)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -81,7 +88,9 @@ def test_osi_trace_hvd(self):
                     self.assertIsInstance(message, HostVehicleData)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -98,7 +107,9 @@ def test_osi_trace_sd(self):
                     self.assertIsInstance(message, SensorData)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -115,7 +126,9 @@ def test_osi_trace_tc(self):
                     self.assertIsInstance(message, TrafficCommand)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -132,7 +145,9 @@ def test_osi_trace_tcu(self):
                     self.assertIsInstance(message, TrafficCommandUpdate)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -149,7 +164,9 @@ def test_osi_trace_tu(self):
                     self.assertIsInstance(message, TrafficUpdate)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -166,7 +183,9 @@ def test_osi_trace_mr(self):
                     self.assertIsInstance(message, MotionRequest)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -183,7 +202,9 @@ def test_osi_trace_su(self):
                     self.assertIsInstance(message, StreamingUpdate)
                     f.write(str(message))
 
-            self.assertEqual(len(trace.retrieve_offsets()), 10)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                self.assertEqual(len(trace.retrieve_offsets()), 10)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -195,8 +216,10 @@ def test_osi_trace_offsets_robustness(self):
 
             trace = OSITrace(path_input)
             # Test whether the function can handle be run multiple times safely
-            offsets = trace.retrieve_offsets(None)
-            offsets2 = trace.retrieve_offsets(None)
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                offsets = trace.retrieve_offsets(None)
+                offsets2 = trace.retrieve_offsets(None)
             trace.close()
 
             self.assertEqual(len(offsets), 10)

From 2a86e4d1d75c185cb5a1bba450b0cb76e57cb1df Mon Sep 17 00:00:00 2001
From: "Pierre R. Mai" <pmai@pmsf.de>
Date: Tue, 28 Oct 2025 15:58:42 +0100
Subject: [PATCH 08/14] Make implementation classes private

Signed-off-by: Pierre R. Mai <pmai@pmsf.de>
---
 osi3trace/osi_trace.py | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index 4e56370..30e2f8e 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -63,9 +63,9 @@ def message_types():
     def __getattr__(self, name):
         """
         This method forwards the getattr call for unsuccessful legacy attribute
-        name lookups to the reader in case it is an OSITraceSingle instance.
+        name lookups to the reader in case it is an _OSITraceSingle instance.
         """
-        if name in self._legacy_ositrace_attributes and isinstance(self.reader, OSITraceSingle):
+        if name in self._legacy_ositrace_attributes and isinstance(self.reader, _OSITraceSingle):
             return getattr(self.reader, name)
         raise AttributeError(f"'{type(self).__name__}' object has no attribute '{name}'")
     
@@ -73,17 +73,17 @@ def __setattr__(self, name, value):
         """
         This method overwrites the default setter and forwards setattr calls for
         legacy attribute names to the reader in case the reader is an
-        OSITraceSingle instance. Otherwise it uses the default setter.
+        _OSITraceSingle instance. Otherwise it uses the default setter.
         """
         reader = super().__getattribute__("reader") if "reader" in self.__dict__ else None
-        if name in self._legacy_ositrace_attributes and isinstance(reader, OSITraceSingle):
+        if name in self._legacy_ositrace_attributes and isinstance(reader, _OSITraceSingle):
             setattr(reader, name, value)
         else:
             super().__setattr__(name, value)
 
     def __dir__(self):
         attrs = super().__dir__()
-        if isinstance(self.reader, OSITraceSingle):
+        if isinstance(self.reader, _OSITraceSingle):
             attrs += list(self._legacy_ositrace_attributes)
         return attrs
     
@@ -107,9 +107,9 @@ def _init_reader(self, path, type_name, cache_messages, topic):
             raise FileNotFoundError("File not found")
 
         if path.suffix.lower() == ".mcap":
-            return OSITraceMulti(path, type_name, topic)
+            return _OSITraceMulti(path, type_name, topic)
         elif path.suffix.lower() in [".osi", ".lzma", ".xz"]:
-            return OSITraceSingle(path, type_name, cache_messages)
+            return _OSITraceSingle(path, type_name, cache_messages)
         else:
             raise ValueError(f"Unsupported file format: '{path.suffix}'")
 
@@ -142,25 +142,25 @@ def close(self):
 
     @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def retrieve_offsets(self, limit=None):
-        if isinstance(self.reader, OSITraceSingle):
+        if isinstance(self.reader, _OSITraceSingle):
             return self.reader.retrieve_offsets(limit)
         raise NotImplementedError("Offsets are only supported for single-channel traces.")
 
     @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def retrieve_message(self, index=None, skip=False):
-        if isinstance(self.reader, OSITraceSingle):
+        if isinstance(self.reader, _OSITraceSingle):
             return self.reader.retrieve_message(index, skip)
         raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
 
     @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def get_message_by_index(self, index):
-        if isinstance(self.reader, OSITraceSingle):
+        if isinstance(self.reader, _OSITraceSingle):
             return self.reader.get_message_by_index(index)
         raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
 
     @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
     def get_messages_in_index_range(self, begin, end):
-        if isinstance(self.reader, OSITraceSingle):
+        if isinstance(self.reader, _OSITraceSingle):
             return self.reader.get_messages_in_index_range(begin, end)
         raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
 
@@ -174,7 +174,7 @@ def get_channel_metadata(self):
         return self.reader.get_channel_metadata()
 
 
-class ReaderBase(ABC):
+class _ReaderBase(ABC):
     """Common interface for trace readers"""
     
     @abstractmethod
@@ -202,7 +202,7 @@ def get_channel_metadata(self):
         pass
 
 
-class OSITraceSingle(ReaderBase):
+class _OSITraceSingle(_ReaderBase):
     """OSI single-channel trace reader"""
     
     def __init__(self, path=None, type_name="SensorView", cache_messages=False):
@@ -353,7 +353,7 @@ def get_channel_metadata(self):
         raise NotImplementedError("Getting channel metadata is only supported for multi-channel traces.")
 
 
-class OSITraceMulti(ReaderBase):
+class _OSITraceMulti(_ReaderBase):
     """OSI multi-channel trace reader"""
 
     def __init__(self, path, type_name, topic):

From 6fa580f1b33730a70203d7e7d88fd75be86788d5 Mon Sep 17 00:00:00 2001
From: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
Date: Mon, 3 Nov 2025 14:45:38 +0100
Subject: [PATCH 09/14] Use static parsing

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
---
 osi3trace/osi_trace.py | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index 30e2f8e..eacd0d9 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -358,7 +358,7 @@ class _OSITraceMulti(_ReaderBase):
 
     def __init__(self, path, type_name, topic):
         self._file = open(path, "rb")
-        self._mcap_reader = make_reader(self._file, decoder_factories=[DecoderFactory()])
+        self._mcap_reader = make_reader(self._file)
         self._iter = None
         self._summary = self._mcap_reader.get_summary()
         available_topics = self.get_available_topics(type_name)
@@ -376,9 +376,14 @@ def restart(self, index=None):
     def __iter__(self):
         """Stateful iterator over the channel's messages in log time order."""
         if self._iter is None:
-            self._iter = self._mcap_reader.iter_decoded_messages(topics=[self.topic])
-        for message in self._iter:
-            yield message.decoded_message
+            self._iter = self._mcap_reader.iter_messages(topics=[self.topic])
+
+        message_class = OSITrace.map_message_type(self.get_message_type())
+
+        for _, _, message in self._iter:
+            msg = message_class()
+            msg.ParseFromString(message.data)
+            yield msg
     
     def close(self):
         if self._file:

From 9ae1254f38c2a956a05488da9246b4b5bd40ec69 Mon Sep 17 00:00:00 2001
From: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
Date: Mon, 3 Nov 2025 14:56:09 +0100
Subject: [PATCH 10/14] Add mcap tests

Signed-off-by: Thomas Sedlmayer <tsedlmayer@pmsfit.de>
---
 tests/test_osi_trace_multi.py | 839 ++++++++++++++++++++++++++++++++++
 1 file changed, 839 insertions(+)
 create mode 100644 tests/test_osi_trace_multi.py

diff --git a/tests/test_osi_trace_multi.py b/tests/test_osi_trace_multi.py
new file mode 100644
index 0000000..1bc2392
--- /dev/null
+++ b/tests/test_osi_trace_multi.py
@@ -0,0 +1,839 @@
+import os
+import tempfile
+import unittest
+import warnings
+
+from osi3trace.osi_trace import OSITrace
+from osi3.osi_sensorview_pb2 import SensorView
+from osi3.osi_sensorviewconfiguration_pb2 import SensorViewConfiguration
+from osi3.osi_groundtruth_pb2 import GroundTruth
+from osi3.osi_hostvehicledata_pb2 import HostVehicleData
+from osi3.osi_sensordata_pb2 import SensorData
+from osi3.osi_trafficcommand_pb2 import TrafficCommand
+from osi3.osi_trafficcommandupdate_pb2 import TrafficCommandUpdate
+from osi3.osi_trafficupdate_pb2 import TrafficUpdate
+from osi3.osi_motionrequest_pb2 import MotionRequest
+from osi3.osi_streamingupdate_pb2 import StreamingUpdate
+
+from mcap.writer import Writer
+from mcap.well_known import MessageEncoding
+
+from google.protobuf.descriptor import FileDescriptor
+from google.protobuf.descriptor_pb2 import FileDescriptorSet
+
+
+class TestOSITraceMulti(unittest.TestCase):
+    def test_osi_trace_sv(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_sv.txth")
+            path_input = os.path.join(tmpdirname, "input_sv.mcap")
+            create_sample_sv(path_input)
+
+            trace = OSITrace(path_input)
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, SensorView)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_svc(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_svc.txth")
+            path_input = os.path.join(tmpdirname, "input_svc.mcap")
+            create_sample_svc(path_input)
+
+            trace = OSITrace(path_input, "SensorViewConfiguration")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, SensorViewConfiguration)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_gt(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_gt.txth")
+            path_input = os.path.join(tmpdirname, "input_gt.mcap")
+            create_sample_gt(path_input)
+
+            trace = OSITrace(path_input, "GroundTruth")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, GroundTruth)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_hvd(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_hvd.txth")
+            path_input = os.path.join(tmpdirname, "input_hvd.mcap")
+            create_sample_hvd(path_input)
+
+            trace = OSITrace(path_input, "HostVehicleData")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, HostVehicleData)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_sd(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_sd.txth")
+            path_input = os.path.join(tmpdirname, "input_sd.mcap")
+            create_sample_sd(path_input)
+
+            trace = OSITrace(path_input, "SensorData")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, SensorData)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_tc(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_tc.txth")
+            path_input = os.path.join(tmpdirname, "input_tc.mcap")
+            create_sample_tc(path_input)
+
+            trace = OSITrace(path_input, "TrafficCommand")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, TrafficCommand)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_tcu(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_tcu.txth")
+            path_input = os.path.join(tmpdirname, "input_tcu.mcap")
+            create_sample_tcu(path_input)
+
+            trace = OSITrace(path_input, "TrafficCommandUpdate")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, TrafficCommandUpdate)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_tu(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_tu.txth")
+            path_input = os.path.join(tmpdirname, "input_tu.mcap")
+            create_sample_tu(path_input)
+
+            trace = OSITrace(path_input, "TrafficUpdate")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, TrafficUpdate)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_mr(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_mr.txth")
+            path_input = os.path.join(tmpdirname, "input_mr.mcap")
+            create_sample_mr(path_input)
+
+            trace = OSITrace(path_input, "MotionRequest")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, MotionRequest)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+    def test_osi_trace_su(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output = os.path.join(tmpdirname, "output_su.txth")
+            path_input = os.path.join(tmpdirname, "input_su.mcap")
+            create_sample_su(path_input)
+
+            trace = OSITrace(path_input, "StreamingUpdate")
+            with open(path_output, "wt") as f:
+                for message in trace:
+                    self.assertIsInstance(message, StreamingUpdate)
+                    f.write(str(message))
+
+            with warnings.catch_warnings():
+                warnings.simplefilter("ignore")
+                try:
+                    self.assertEqual(len(trace.retrieve_offsets()), 10)
+                except NotImplementedError:
+                    pass
+            trace.close()
+
+            self.assertTrue(os.path.exists(path_output))
+
+
+def build_file_descriptor_set(message_class) -> FileDescriptorSet:
+        file_descriptor_set = FileDescriptorSet()
+        seen_dependencies = set()
+
+        def append_file_descriptor(file_descriptor: FileDescriptor):
+            for dep in file_descriptor.dependencies:
+                if dep.name not in seen_dependencies:
+                    seen_dependencies.add(dep.name)
+                    append_file_descriptor(dep)
+            file_descriptor.CopyToProto(file_descriptor_set.file.add())
+
+        append_file_descriptor(message_class.DESCRIPTOR.file)
+        return file_descriptor_set
+
+
+def create_sample_sv(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(SensorView)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.SensorView",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "SensorViewTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    sensorview = SensorView()
+
+    sensorview.version.version_major = 3
+    sensorview.version.version_minor = 0
+    sensorview.version.version_patch = 0
+
+    sensorview.timestamp.seconds = 0
+    sensorview.timestamp.nanos = 0
+
+    sensorview.sensor_id.value = 42
+
+    sensorview.host_vehicle_id.value = 114
+
+    sv_ground_truth = sensorview.global_ground_truth
+    sv_ground_truth.version.version_major = 3
+    sv_ground_truth.version.version_minor = 0
+    sv_ground_truth.version.version_patch = 0
+
+    sv_ground_truth.timestamp.seconds = 0
+    sv_ground_truth.timestamp.nanos = 0
+
+    sv_ground_truth.host_vehicle_id.value = 114
+
+    moving_object = sv_ground_truth.moving_object.add()
+    moving_object.id.value = 114
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        sensorview.timestamp.seconds += 1
+        sensorview.timestamp.nanos += 100000
+
+        sv_ground_truth.timestamp.seconds += 1
+        sv_ground_truth.timestamp.nanos += 100000
+
+        moving_object.vehicle_classification.type = 2
+
+        moving_object.base.dimension.length = 5
+        moving_object.base.dimension.width = 2
+        moving_object.base.dimension.height = 1
+
+        moving_object.base.position.x = 0.0 + i
+        moving_object.base.position.y = 0.0
+        moving_object.base.position.z = 0.0
+
+        moving_object.base.orientation.roll = 0.0
+        moving_object.base.orientation.pitch = 0.0
+        moving_object.base.orientation.yaw = 0.0
+
+        time = sensorview.timestamp.seconds + sensorview.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=sensorview.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_svc(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(SensorViewConfiguration)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.SensorViewConfiguration",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "SensorViewConfigurationTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    sensorviewconfig = SensorViewConfiguration()
+
+    sensorviewconfig.version.version_major = 3
+    sensorviewconfig.version.version_minor = 0
+    sensorviewconfig.version.version_patch = 0
+
+    sensorviewconfig.sensor_id.value = 42
+
+    sensorviewconfig.mounting_position.position.x = 0.8
+    sensorviewconfig.mounting_position.position.y = 1.0
+    sensorviewconfig.mounting_position.position.z = 0.5
+
+    sensorviewconfig.mounting_position.orientation.roll = 0.10
+    sensorviewconfig.mounting_position.orientation.pitch = 0.15
+    sensorviewconfig.mounting_position.orientation.yaw = 0.25
+
+    time = 0
+    mcap_writer.add_message(
+        channel_id=channel_id,
+        log_time=int(time*1000000000),
+        data=sensorviewconfig.SerializeToString(),
+        publish_time=int(time*1000000000),
+    )
+
+    mcap_writer.finish()
+
+
+def create_sample_gt(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(GroundTruth)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.GroundTruth",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "GroundTruthTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    ground_truth = GroundTruth()
+
+    ground_truth.version.version_major = 3
+    ground_truth.version.version_minor = 0
+    ground_truth.version.version_patch = 0
+
+    ground_truth.timestamp.seconds = 0
+    ground_truth.timestamp.nanos = 0
+
+    moving_object = ground_truth.moving_object.add()
+    moving_object.id.value = 114
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        ground_truth.timestamp.seconds += 1
+        ground_truth.timestamp.nanos += 100000
+
+        moving_object.vehicle_classification.type = 2
+
+        moving_object.base.dimension.length = 5
+        moving_object.base.dimension.width = 2
+        moving_object.base.dimension.height = 1
+
+        moving_object.base.position.x = 0.0 + i
+        moving_object.base.position.y = 0.0
+        moving_object.base.position.z = 0.0
+
+        moving_object.base.orientation.roll = 0.0
+        moving_object.base.orientation.pitch = 0.0
+        moving_object.base.orientation.yaw = 0.0
+
+        time = ground_truth.timestamp.seconds + ground_truth.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=ground_truth.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_hvd(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(HostVehicleData)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.HostVehicleData",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "HostVehicleDataTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    hostvehicledata = HostVehicleData()
+
+    hostvehicledata.version.version_major = 3
+    hostvehicledata.version.version_minor = 0
+    hostvehicledata.version.version_patch = 0
+
+    hostvehicledata.timestamp.seconds = 0
+    hostvehicledata.timestamp.nanos = 0
+
+    hostvehicledata.host_vehicle_id.value = 114
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        hostvehicledata.timestamp.seconds += 1
+        hostvehicledata.timestamp.nanos += 100000
+
+        hostvehicledata.location.dimension.length = 5
+        hostvehicledata.location.dimension.width = 2
+        hostvehicledata.location.dimension.height = 1
+
+        hostvehicledata.location.position.x = 0.0 + i
+        hostvehicledata.location.position.y = 0.0
+        hostvehicledata.location.position.z = 0.0
+
+        hostvehicledata.location.orientation.roll = 0.0
+        hostvehicledata.location.orientation.pitch = 0.0
+        hostvehicledata.location.orientation.yaw = 0.0
+
+        time = hostvehicledata.timestamp.seconds + hostvehicledata.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=hostvehicledata.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_sd(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(SensorData)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.SensorData",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "SensorDataTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    sensordata = SensorData()
+
+    sensordata.version.version_major = 3
+    sensordata.version.version_minor = 0
+    sensordata.version.version_patch = 0
+
+    sensordata.timestamp.seconds = 0
+    sensordata.timestamp.nanos = 0
+
+    sensordata.sensor_id.value = 42
+
+    moving_object = sensordata.moving_object.add()
+    moving_object.header.tracking_id.value = 1
+    gt_id = moving_object.header.ground_truth_id.add()
+    gt_id.value = 114
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        sensordata.timestamp.seconds += 1
+        sensordata.timestamp.nanos += 100000
+
+        moving_object.base.dimension.length = 5
+        moving_object.base.dimension.width = 2
+        moving_object.base.dimension.height = 1
+
+        moving_object.base.position.x = 0.0 + i
+        moving_object.base.position.y = 0.0
+        moving_object.base.position.z = 0.0
+
+        moving_object.base.orientation.roll = 0.0
+        moving_object.base.orientation.pitch = 0.0
+        moving_object.base.orientation.yaw = 0.0
+
+        time = sensordata.timestamp.seconds + sensordata.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=sensordata.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_tc(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(TrafficCommand)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.TrafficCommand",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "TrafficCommandTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    trafficcommand = TrafficCommand()
+
+    trafficcommand.version.version_major = 3
+    trafficcommand.version.version_minor = 0
+    trafficcommand.version.version_patch = 0
+
+    trafficcommand.timestamp.seconds = 0
+    trafficcommand.timestamp.nanos = 0
+
+    trafficcommand.traffic_participant_id.value = 114
+
+    action = trafficcommand.action.add()
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        trafficcommand.timestamp.seconds += 1
+        trafficcommand.timestamp.nanos += 100000
+
+        action.speed_action.action_header.action_id.value = 1000 + i
+
+        action.speed_action.absolute_target_speed = 10.0 + 0.5 * i
+
+        time = trafficcommand.timestamp.seconds + trafficcommand.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=trafficcommand.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_tcu(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(TrafficCommandUpdate)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.TrafficCommandUpdate",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "TrafficCommandUpdateTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    trafficcommandupdate = TrafficCommandUpdate()
+
+    trafficcommandupdate.version.version_major = 3
+    trafficcommandupdate.version.version_minor = 0
+    trafficcommandupdate.version.version_patch = 0
+
+    trafficcommandupdate.timestamp.seconds = 0
+    trafficcommandupdate.timestamp.nanos = 0
+
+    trafficcommandupdate.traffic_participant_id.value = 114
+
+    action = trafficcommandupdate.dismissed_action.add()
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        trafficcommandupdate.timestamp.seconds += 1
+        trafficcommandupdate.timestamp.nanos += 100000
+
+        action.dismissed_action_id.value = 1000 + i
+        action.failure_reason = "Cannot complete!"
+
+        time = trafficcommandupdate.timestamp.seconds + trafficcommandupdate.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=trafficcommandupdate.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_tu(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(TrafficUpdate)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.TrafficUpdate",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "TrafficUpdateTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    trafficupdate = TrafficUpdate()
+
+    trafficupdate.version.version_major = 3
+    trafficupdate.version.version_minor = 0
+    trafficupdate.version.version_patch = 0
+
+    trafficupdate.timestamp.seconds = 0
+    trafficupdate.timestamp.nanos = 0
+
+    moving_object = trafficupdate.update.add()
+    moving_object.id.value = 114
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        trafficupdate.timestamp.seconds += 1
+        trafficupdate.timestamp.nanos += 100000
+
+        moving_object.vehicle_classification.type = 2
+
+        moving_object.base.dimension.length = 5
+        moving_object.base.dimension.width = 2
+        moving_object.base.dimension.height = 1
+
+        moving_object.base.position.x = 0.0 + i
+        moving_object.base.position.y = 0.0
+        moving_object.base.position.z = 0.0
+
+        moving_object.base.orientation.roll = 0.0
+        moving_object.base.orientation.pitch = 0.0
+        moving_object.base.orientation.yaw = 0.0
+
+        time = trafficupdate.timestamp.seconds + trafficupdate.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=trafficupdate.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_mr(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(MotionRequest)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.MotionRequest",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "MotionRequestTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    motionrequest = MotionRequest()
+
+    motionrequest.version.version_major = 3
+    motionrequest.version.version_minor = 0
+    motionrequest.version.version_patch = 0
+
+    motionrequest.timestamp.seconds = 0
+    motionrequest.timestamp.nanos = 0
+
+    desired_state = motionrequest.desired_state
+
+    desired_state.timestamp.seconds = 0
+    desired_state.timestamp.nanos = 0
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        motionrequest.timestamp.seconds += 1
+        motionrequest.timestamp.nanos += 100000
+
+        desired_state.timestamp.seconds += 1
+        desired_state.timestamp.nanos += 100000
+
+        desired_state.position.x = 0.0 + i
+        desired_state.position.y = 0.0
+        desired_state.position.z = 0.0
+
+        desired_state.orientation.roll = 0.0
+        desired_state.orientation.pitch = 0.0
+        desired_state.orientation.yaw = 0.10
+
+        time = motionrequest.timestamp.seconds + motionrequest.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=motionrequest.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()
+
+
+def create_sample_su(path):
+    mcap_writer = Writer(output=str(path),)
+    file_descriptor_set = build_file_descriptor_set(StreamingUpdate)
+    schema_id = mcap_writer.register_schema(
+        name="osi3.StreamingUpdate",
+        encoding=MessageEncoding.Protobuf,
+        data=file_descriptor_set.SerializeToString(),
+    )
+    topic_name = "StreamingUpdateTopic"
+    channel_id = mcap_writer.register_channel(
+        topic=topic_name,
+        message_encoding=MessageEncoding.Protobuf,
+        schema_id=schema_id,
+        metadata={},
+    )
+    mcap_writer.start(library=f"osi-python mcap tests")
+
+    streamingupdate = StreamingUpdate()
+
+    streamingupdate.version.version_major = 3
+    streamingupdate.version.version_minor = 0
+    streamingupdate.version.version_patch = 0
+
+    streamingupdate.timestamp.seconds = 0
+    streamingupdate.timestamp.nanos = 0
+
+    moving_object = streamingupdate.moving_object_update.add()
+    moving_object.id.value = 114
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        streamingupdate.timestamp.seconds += 1
+        streamingupdate.timestamp.nanos += 100000
+
+        moving_object.vehicle_classification.type = 2
+
+        moving_object.base.dimension.length = 5
+        moving_object.base.dimension.width = 2
+        moving_object.base.dimension.height = 1
+
+        moving_object.base.position.x = 0.0 + i
+        moving_object.base.position.y = 0.0
+        moving_object.base.position.z = 0.0
+
+        moving_object.base.orientation.roll = 0.0
+        moving_object.base.orientation.pitch = 0.0
+        moving_object.base.orientation.yaw = 0.0
+
+        time = streamingupdate.timestamp.seconds + streamingupdate.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_id,
+            log_time=int(time*1000000000),
+            data=streamingupdate.SerializeToString(),
+            publish_time=int(time*1000000000),
+        )
+
+    mcap_writer.finish()

From 49cc9d2345851525310a438ef00468be99d1ffa7 Mon Sep 17 00:00:00 2001
From: "Pierre R. Mai" <pmai@pmsf.de>
Date: Tue, 4 Nov 2025 11:08:50 +0100
Subject: [PATCH 11/14] Add meta-data handling, refactor multi tests

Signed-off-by: Pierre R. Mai <pmai@pmsf.de>
---
 tests/test_osi_trace_multi.py | 261 ++++++++++++----------------------
 1 file changed, 90 insertions(+), 171 deletions(-)

diff --git a/tests/test_osi_trace_multi.py b/tests/test_osi_trace_multi.py
index 1bc2392..3e6f930 100644
--- a/tests/test_osi_trace_multi.py
+++ b/tests/test_osi_trace_multi.py
@@ -4,6 +4,7 @@
 import warnings
 
 from osi3trace.osi_trace import OSITrace
+from osi3 import __version__ as osi3_version
 from osi3.osi_sensorview_pb2 import SensorView
 from osi3.osi_sensorviewconfiguration_pb2 import SensorViewConfiguration
 from osi3.osi_groundtruth_pb2 import GroundTruth
@@ -18,6 +19,7 @@
 from mcap.writer import Writer
 from mcap.well_known import MessageEncoding
 
+from google.protobuf import __version__ as google_protobuf_version
 from google.protobuf.descriptor import FileDescriptor
 from google.protobuf.descriptor_pb2 import FileDescriptorSet
 
@@ -245,36 +247,63 @@ def test_osi_trace_su(self):
 
 
 def build_file_descriptor_set(message_class) -> FileDescriptorSet:
-        file_descriptor_set = FileDescriptorSet()
-        seen_dependencies = set()
+    file_descriptor_set = FileDescriptorSet()
+    seen_dependencies = set()
 
-        def append_file_descriptor(file_descriptor: FileDescriptor):
-            for dep in file_descriptor.dependencies:
-                if dep.name not in seen_dependencies:
-                    seen_dependencies.add(dep.name)
-                    append_file_descriptor(dep)
-            file_descriptor.CopyToProto(file_descriptor_set.file.add())
+    def append_file_descriptor(file_descriptor: FileDescriptor):
+        for dep in file_descriptor.dependencies:
+            if dep.name not in seen_dependencies:
+                seen_dependencies.add(dep.name)
+                append_file_descriptor(dep)
+        file_descriptor.CopyToProto(file_descriptor_set.file.add())
 
-        append_file_descriptor(message_class.DESCRIPTOR.file)
-        return file_descriptor_set
+    append_file_descriptor(message_class.DESCRIPTOR.file)
+    return file_descriptor_set
 
 
-def create_sample_sv(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(SensorView)
+def prepare_mcap_writer(path):
+    mcap_writer = Writer(
+        output=str(path),
+    )
+
+    mcap_writer.start(library=f"osi-python mcap test suite")
+    mcap_writer.add_metadata(
+        name="net.asam.osi.trace",
+        data={
+            "version": osi3_version,
+            "min_osi_version": osi3_version,
+            "max_osi_version": osi3_version,
+            "min_protobuf_version": google_protobuf_version,
+            "max_protobuf_version": google_protobuf_version,
+            "description": "Test trace created by osi-python test suite",
+        },
+    )
+    return mcap_writer
+
+
+def add_channel(mcap_writer, message_class, topic_name):
+    file_descriptor_set = build_file_descriptor_set(message_class)
     schema_id = mcap_writer.register_schema(
-        name="osi3.SensorView",
+        name=f"osi3.{message_class.__name__}",
         encoding=MessageEncoding.Protobuf,
         data=file_descriptor_set.SerializeToString(),
     )
-    topic_name = "SensorViewTopic"
     channel_id = mcap_writer.register_channel(
         topic=topic_name,
         message_encoding=MessageEncoding.Protobuf,
         schema_id=schema_id,
-        metadata={},
+        metadata={
+            "net.asam.osi.trace.channel.osi_version": osi3_version,
+            "net.asam.osi.trace.channel.protobuf_version": google_protobuf_version,
+            "net.asam.osi.trace.channel.description": f"Channel for OSI message type {message_class.__name__}",
+        },
     )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    return channel_id
+
+
+def create_sample_sv(path):
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, SensorView, "SensorViewTopic")
 
     sensorview = SensorView()
 
@@ -328,30 +357,19 @@ def create_sample_sv(path):
         time = sensorview.timestamp.seconds + sensorview.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=sensorview.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_svc(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(SensorViewConfiguration)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.SensorViewConfiguration",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(
+        mcap_writer, SensorViewConfiguration, "SensorViewConfigurationTopic"
     )
-    topic_name = "SensorViewConfigurationTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
 
     sensorviewconfig = SensorViewConfiguration()
 
@@ -372,30 +390,17 @@ def create_sample_svc(path):
     time = 0
     mcap_writer.add_message(
         channel_id=channel_id,
-        log_time=int(time*1000000000),
+        log_time=int(time * 1000000000),
         data=sensorviewconfig.SerializeToString(),
-        publish_time=int(time*1000000000),
+        publish_time=int(time * 1000000000),
     )
 
     mcap_writer.finish()
 
 
 def create_sample_gt(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(GroundTruth)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.GroundTruth",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
-    )
-    topic_name = "GroundTruthTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, GroundTruth, "GroundTruthTopic")
 
     ground_truth = GroundTruth()
 
@@ -432,30 +437,17 @@ def create_sample_gt(path):
         time = ground_truth.timestamp.seconds + ground_truth.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=ground_truth.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_hvd(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(HostVehicleData)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.HostVehicleData",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
-    )
-    topic_name = "HostVehicleDataTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, HostVehicleData, "HostVehicleDataTopic")
 
     hostvehicledata = HostVehicleData()
 
@@ -489,30 +481,17 @@ def create_sample_hvd(path):
         time = hostvehicledata.timestamp.seconds + hostvehicledata.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=hostvehicledata.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_sd(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(SensorData)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.SensorData",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
-    )
-    topic_name = "SensorDataTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, SensorData, "SensorDataTopic")
 
     sensordata = SensorData()
 
@@ -551,30 +530,17 @@ def create_sample_sd(path):
         time = sensordata.timestamp.seconds + sensordata.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=sensordata.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_tc(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(TrafficCommand)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.TrafficCommand",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
-    )
-    topic_name = "TrafficCommandTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, TrafficCommand, "TrafficCommandTopic")
 
     trafficcommand = TrafficCommand()
 
@@ -602,30 +568,19 @@ def create_sample_tc(path):
         time = trafficcommand.timestamp.seconds + trafficcommand.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=trafficcommand.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_tcu(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(TrafficCommandUpdate)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.TrafficCommandUpdate",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(
+        mcap_writer, TrafficCommandUpdate, "TrafficCommandUpdateTopic"
     )
-    topic_name = "TrafficCommandUpdateTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
 
     trafficcommandupdate = TrafficCommandUpdate()
 
@@ -649,33 +604,23 @@ def create_sample_tcu(path):
         action.dismissed_action_id.value = 1000 + i
         action.failure_reason = "Cannot complete!"
 
-        time = trafficcommandupdate.timestamp.seconds + trafficcommandupdate.timestamp.nanos / 1e9
+        time = (
+            trafficcommandupdate.timestamp.seconds
+            + trafficcommandupdate.timestamp.nanos / 1e9
+        )
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=trafficcommandupdate.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_tu(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(TrafficUpdate)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.TrafficUpdate",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
-    )
-    topic_name = "TrafficUpdateTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, TrafficUpdate, "TrafficUpdateTopic")
 
     trafficupdate = TrafficUpdate()
 
@@ -712,30 +657,17 @@ def create_sample_tu(path):
         time = trafficupdate.timestamp.seconds + trafficupdate.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=trafficupdate.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_mr(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(MotionRequest)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.MotionRequest",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
-    )
-    topic_name = "MotionRequestTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, MotionRequest, "MotionRequestTopic")
 
     motionrequest = MotionRequest()
 
@@ -771,30 +703,17 @@ def create_sample_mr(path):
         time = motionrequest.timestamp.seconds + motionrequest.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=motionrequest.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()
 
 
 def create_sample_su(path):
-    mcap_writer = Writer(output=str(path),)
-    file_descriptor_set = build_file_descriptor_set(StreamingUpdate)
-    schema_id = mcap_writer.register_schema(
-        name="osi3.StreamingUpdate",
-        encoding=MessageEncoding.Protobuf,
-        data=file_descriptor_set.SerializeToString(),
-    )
-    topic_name = "StreamingUpdateTopic"
-    channel_id = mcap_writer.register_channel(
-        topic=topic_name,
-        message_encoding=MessageEncoding.Protobuf,
-        schema_id=schema_id,
-        metadata={},
-    )
-    mcap_writer.start(library=f"osi-python mcap tests")
+    mcap_writer = prepare_mcap_writer(path)
+    channel_id = add_channel(mcap_writer, StreamingUpdate, "StreamingUpdateTopic")
 
     streamingupdate = StreamingUpdate()
 
@@ -831,9 +750,9 @@ def create_sample_su(path):
         time = streamingupdate.timestamp.seconds + streamingupdate.timestamp.nanos / 1e9
         mcap_writer.add_message(
             channel_id=channel_id,
-            log_time=int(time*1000000000),
+            log_time=int(time * 1000000000),
             data=streamingupdate.SerializeToString(),
-            publish_time=int(time*1000000000),
+            publish_time=int(time * 1000000000),
         )
 
     mcap_writer.finish()

From 37cb4d1024054dd2fcb6ca145b71c48e819920a9 Mon Sep 17 00:00:00 2001
From: "Pierre R. Mai" <pmai@pmsf.de>
Date: Tue, 4 Nov 2025 11:26:37 +0100
Subject: [PATCH 12/14] Adjust length checking code to multi trace

Signed-off-by: Pierre R. Mai <pmai@pmsf.de>
---
 tests/test_osi_trace_multi.py | 72 ++++++++++++++++++++---------------
 1 file changed, 41 insertions(+), 31 deletions(-)

diff --git a/tests/test_osi_trace_multi.py b/tests/test_osi_trace_multi.py
index 3e6f930..9254c7f 100644
--- a/tests/test_osi_trace_multi.py
+++ b/tests/test_osi_trace_multi.py
@@ -33,16 +33,17 @@ def test_osi_trace_sv(self):
 
             trace = OSITrace(path_input)
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, SensorView)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -55,16 +56,17 @@ def test_osi_trace_svc(self):
 
             trace = OSITrace(path_input, "SensorViewConfiguration")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, SensorViewConfiguration)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 1)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
-                    self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
+                with self.assertRaises(NotImplementedError):
+                    self.assertEqual(len(trace.retrieve_offsets()), 1)
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -77,16 +79,17 @@ def test_osi_trace_gt(self):
 
             trace = OSITrace(path_input, "GroundTruth")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, GroundTruth)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -99,16 +102,17 @@ def test_osi_trace_hvd(self):
 
             trace = OSITrace(path_input, "HostVehicleData")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, HostVehicleData)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -121,16 +125,17 @@ def test_osi_trace_sd(self):
 
             trace = OSITrace(path_input, "SensorData")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, SensorData)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -143,16 +148,17 @@ def test_osi_trace_tc(self):
 
             trace = OSITrace(path_input, "TrafficCommand")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, TrafficCommand)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -165,16 +171,17 @@ def test_osi_trace_tcu(self):
 
             trace = OSITrace(path_input, "TrafficCommandUpdate")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, TrafficCommandUpdate)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -187,16 +194,17 @@ def test_osi_trace_tu(self):
 
             trace = OSITrace(path_input, "TrafficUpdate")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, TrafficUpdate)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -209,16 +217,17 @@ def test_osi_trace_mr(self):
 
             trace = OSITrace(path_input, "MotionRequest")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, MotionRequest)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))
@@ -231,16 +240,17 @@ def test_osi_trace_su(self):
 
             trace = OSITrace(path_input, "StreamingUpdate")
             with open(path_output, "wt") as f:
+                count = 0
                 for message in trace:
                     self.assertIsInstance(message, StreamingUpdate)
+                    count += 1
                     f.write(str(message))
+                self.assertEqual(count, 10)
 
             with warnings.catch_warnings():
                 warnings.simplefilter("ignore")
-                try:
+                with self.assertRaises(NotImplementedError):
                     self.assertEqual(len(trace.retrieve_offsets()), 10)
-                except NotImplementedError:
-                    pass
             trace.close()
 
             self.assertTrue(os.path.exists(path_output))

From 958381475951de7a2f591fac8375589be5d77f34 Mon Sep 17 00:00:00 2001
From: "Pierre R. Mai" <pmai@pmsf.de>
Date: Tue, 4 Nov 2025 11:41:17 +0100
Subject: [PATCH 13/14] Add multi-channel test case with type checks

Signed-off-by: Pierre R. Mai <pmai@pmsf.de>
---
 tests/test_osi_trace_multi.py | 157 ++++++++++++++++++++++++++++++++++
 1 file changed, 157 insertions(+)

diff --git a/tests/test_osi_trace_multi.py b/tests/test_osi_trace_multi.py
index 9254c7f..de67b8d 100644
--- a/tests/test_osi_trace_multi.py
+++ b/tests/test_osi_trace_multi.py
@@ -255,6 +255,59 @@ def test_osi_trace_su(self):
 
             self.assertTrue(os.path.exists(path_output))
 
+    def test_osi_trace_sv_and_sd(self):
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            path_output1 = os.path.join(tmpdirname, "output_svsd1.txth")
+            path_output2 = os.path.join(tmpdirname, "output_svsd2.txth")
+            path_output3 = os.path.join(tmpdirname, "output_svsd3.txth")
+            path_input = os.path.join(tmpdirname, "input_svsd.mcap")
+            create_sample_svsd(path_input)
+
+            # Select channel via type name
+            trace = OSITrace(path_input, "SensorView")
+            with open(path_output1, "wt") as f:
+                count = 0
+                for message in trace:
+                    self.assertIsInstance(message, SensorView)
+                    count += 1
+                    f.write(str(message))
+                self.assertEqual(count, 10)
+            trace.close()
+
+            # Select channel via type name
+            trace = OSITrace(path_input, "SensorData")
+            with open(path_output2, "wt") as f:
+                count = 0
+                for message in trace:
+                    self.assertIsInstance(message, SensorData)
+                    count += 1
+                    f.write(str(message))
+                self.assertEqual(count, 10)
+            trace.close()
+
+            # Select channel via channel name and type name
+            trace = OSITrace(path_input, "SensorData", False, "SensorDataTopic")
+            with open(path_output3, "wt") as f:
+                count = 0
+                for message in trace:
+                    self.assertIsInstance(message, SensorData)
+                    count += 1
+                    f.write(str(message))
+                self.assertEqual(count, 10)
+            trace.close()
+
+            # Mismatched channel name and type name
+            with self.assertRaises(ValueError):
+                trace = OSITrace(path_input, "SensorData", False, "SensorViewTopic")
+
+            # Unknown channel name
+            with self.assertRaises(ValueError):
+                trace = OSITrace(path_input, "SensorData", False, "UnknownTopic")
+
+            self.assertTrue(os.path.exists(path_output1))
+            self.assertTrue(os.path.exists(path_output2))
+            self.assertTrue(os.path.exists(path_output3))
+
 
 def build_file_descriptor_set(message_class) -> FileDescriptorSet:
     file_descriptor_set = FileDescriptorSet()
@@ -766,3 +819,107 @@ def create_sample_su(path):
         )
 
     mcap_writer.finish()
+
+
+def create_sample_svsd(path):
+    mcap_writer = prepare_mcap_writer(path)
+    channel_sv = add_channel(mcap_writer, SensorView, "SensorViewTopic")
+    channel_sd = add_channel(mcap_writer, SensorData, "SensorDataTopic")
+
+    sensorview = SensorView()
+
+    sensorview.version.version_major = 3
+    sensorview.version.version_minor = 0
+    sensorview.version.version_patch = 0
+
+    sensorview.timestamp.seconds = 0
+    sensorview.timestamp.nanos = 0
+
+    sensorview.sensor_id.value = 42
+
+    sensorview.host_vehicle_id.value = 114
+
+    sv_ground_truth = sensorview.global_ground_truth
+    sv_ground_truth.version.version_major = 3
+    sv_ground_truth.version.version_minor = 0
+    sv_ground_truth.version.version_patch = 0
+
+    sv_ground_truth.timestamp.seconds = 0
+    sv_ground_truth.timestamp.nanos = 0
+
+    sv_ground_truth.host_vehicle_id.value = 114
+
+    moving_object = sv_ground_truth.moving_object.add()
+    moving_object.id.value = 114
+
+    sensordata = SensorData()
+
+    sensordata.version.version_major = 3
+    sensordata.version.version_minor = 0
+    sensordata.version.version_patch = 0
+
+    sensordata.timestamp.seconds = 0
+    sensordata.timestamp.nanos = 0
+
+    sensordata.sensor_id.value = 42
+
+    sdmoving_object = sensordata.moving_object.add()
+    sdmoving_object.header.tracking_id.value = 1
+    gt_id = sdmoving_object.header.ground_truth_id.add()
+    gt_id.value = 114
+
+    # Generate 10 OSI messages for 9 seconds
+    for i in range(10):
+        # Increment the time
+        sensorview.timestamp.seconds += 1
+        sensorview.timestamp.nanos += 100000
+
+        sv_ground_truth.timestamp.seconds += 1
+        sv_ground_truth.timestamp.nanos += 100000
+
+        sensordata.timestamp.seconds += 1
+        sensordata.timestamp.nanos += 100000
+
+        # SensorView moving object
+        moving_object.vehicle_classification.type = 2
+
+        moving_object.base.dimension.length = 5
+        moving_object.base.dimension.width = 2
+        moving_object.base.dimension.height = 1
+
+        moving_object.base.position.x = 0.0 + i
+        moving_object.base.position.y = 0.0
+        moving_object.base.position.z = 0.0
+
+        moving_object.base.orientation.roll = 0.0
+        moving_object.base.orientation.pitch = 0.0
+        moving_object.base.orientation.yaw = 0.0
+
+        # SensorData moving object
+        sdmoving_object.base.dimension.length = 5
+        sdmoving_object.base.dimension.width = 2
+        sdmoving_object.base.dimension.height = 1
+
+        sdmoving_object.base.position.x = 0.0 + i
+        sdmoving_object.base.position.y = 0.0
+        sdmoving_object.base.position.z = 0.0
+
+        sdmoving_object.base.orientation.roll = 0.0
+        sdmoving_object.base.orientation.pitch = 0.0
+        sdmoving_object.base.orientation.yaw = 0.0
+
+        time = sensorview.timestamp.seconds + sensorview.timestamp.nanos / 1e9
+        mcap_writer.add_message(
+            channel_id=channel_sv,
+            log_time=int(time * 1000000000),
+            data=sensorview.SerializeToString(),
+            publish_time=int(time * 1000000000),
+        )
+        mcap_writer.add_message(
+            channel_id=channel_sd,
+            log_time=int(time * 1000000000),
+            data=sensordata.SerializeToString(),
+            publish_time=int(time * 1000000000),
+        )
+
+    mcap_writer.finish()

From 7ee607f20625941b165795faa04ad12ca98ac47f Mon Sep 17 00:00:00 2001
From: "Pierre R. Mai" <pmai@pmsf.de>
Date: Tue, 4 Nov 2025 11:42:57 +0100
Subject: [PATCH 14/14] Reformat with black settings

Signed-off-by: Pierre R. Mai <pmai@pmsf.de>
---
 osi3trace/osi_trace.py | 118 ++++++++++++++++++++++++++++-------------
 1 file changed, 81 insertions(+), 37 deletions(-)

diff --git a/osi3trace/osi_trace.py b/osi3trace/osi_trace.py
index eacd0d9..a3ed619 100644
--- a/osi3trace/osi_trace.py
+++ b/osi3trace/osi_trace.py
@@ -40,7 +40,7 @@
 
 class OSITrace:
     """This class can import and decode OSI single- and multi-channel trace files."""
-    
+
     @staticmethod
     def map_message_type(type_name):
         """Map the type name to the protobuf message type."""
@@ -50,7 +50,7 @@ def map_message_type(type_name):
     def message_types():
         """Message types that OSITrace supports."""
         return list(MESSAGES_TYPE.keys())
-    
+
     _legacy_ositrace_attributes = {
         "type",
         "file",
@@ -65,18 +65,26 @@ def __getattr__(self, name):
         This method forwards the getattr call for unsuccessful legacy attribute
         name lookups to the reader in case it is an _OSITraceSingle instance.
         """
-        if name in self._legacy_ositrace_attributes and isinstance(self.reader, _OSITraceSingle):
+        if name in self._legacy_ositrace_attributes and isinstance(
+            self.reader, _OSITraceSingle
+        ):
             return getattr(self.reader, name)
-        raise AttributeError(f"'{type(self).__name__}' object has no attribute '{name}'")
-    
+        raise AttributeError(
+            f"'{type(self).__name__}' object has no attribute '{name}'"
+        )
+
     def __setattr__(self, name, value):
         """
         This method overwrites the default setter and forwards setattr calls for
         legacy attribute names to the reader in case the reader is an
         _OSITraceSingle instance. Otherwise it uses the default setter.
         """
-        reader = super().__getattribute__("reader") if "reader" in self.__dict__ else None
-        if name in self._legacy_ositrace_attributes and isinstance(reader, _OSITraceSingle):
+        reader = (
+            super().__getattribute__("reader") if "reader" in self.__dict__ else None
+        )
+        if name in self._legacy_ositrace_attributes and isinstance(
+            reader, _OSITraceSingle
+        ):
             setattr(reader, name, value)
         else:
             super().__setattr__(name, value)
@@ -86,11 +94,13 @@ def __dir__(self):
         if isinstance(self.reader, _OSITraceSingle):
             attrs += list(self._legacy_ositrace_attributes)
         return attrs
-    
-    def __init__(self, path=None, type_name="SensorView", cache_messages=False, topic=None):
+
+    def __init__(
+        self, path=None, type_name="SensorView", cache_messages=False, topic=None
+    ):
         """
         Initializes the trace reader depending on the trace file format.
-        
+
         Args:
             path (str): The path to the trace file.
             type_name (str): The type name of the messages in the trace; check supported message types with `OSITrace.message_types()`.
@@ -100,8 +110,10 @@ def __init__(self, path=None, type_name="SensorView", cache_messages=False, topi
         self.reader = None
 
         if path is not None:
-            self.reader = self._init_reader(Path(path), type_name, cache_messages, topic)
-            
+            self.reader = self._init_reader(
+                Path(path), type_name, cache_messages, topic
+            )
+
     def _init_reader(self, path, type_name, cache_messages, topic):
         if not path.exists():
             raise FileNotFoundError("File not found")
@@ -116,7 +128,7 @@ def _init_reader(self, path, type_name, cache_messages, topic):
     def from_file(self, path, type_name="SensorView", cache_messages=False, topic=None):
         """
         Initializes the trace reader depending on the trace file format.
-        
+
         Args:
             path (str): The path to the trace file.
             type_name (str): The type name of the messages in the trace; check supported message types with `OSITrace.message_types()`.
@@ -140,47 +152,63 @@ def __iter__(self):
     def close(self):
         return self.reader.close()
 
-    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
+    @deprecated(
+        "This is a legacy interface only supported for single-channel traces, which will be removed in future versions."
+    )
     def retrieve_offsets(self, limit=None):
         if isinstance(self.reader, _OSITraceSingle):
             return self.reader.retrieve_offsets(limit)
-        raise NotImplementedError("Offsets are only supported for single-channel traces.")
+        raise NotImplementedError(
+            "Offsets are only supported for single-channel traces."
+        )
 
-    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
+    @deprecated(
+        "This is a legacy interface only supported for single-channel traces, which will be removed in future versions."
+    )
     def retrieve_message(self, index=None, skip=False):
         if isinstance(self.reader, _OSITraceSingle):
             return self.reader.retrieve_message(index, skip)
-        raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
+        raise NotImplementedError(
+            "Index-based message retrieval is only supported for single-channel traces."
+        )
 
-    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
+    @deprecated(
+        "This is a legacy interface only supported for single-channel traces, which will be removed in future versions."
+    )
     def get_message_by_index(self, index):
         if isinstance(self.reader, _OSITraceSingle):
             return self.reader.get_message_by_index(index)
-        raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
+        raise NotImplementedError(
+            "Index-based message retrieval is only supported for single-channel traces."
+        )
 
-    @deprecated("This is a legacy interface only supported for single-channel traces, which will be removed in future versions.")
+    @deprecated(
+        "This is a legacy interface only supported for single-channel traces, which will be removed in future versions."
+    )
     def get_messages_in_index_range(self, begin, end):
         if isinstance(self.reader, _OSITraceSingle):
             return self.reader.get_messages_in_index_range(begin, end)
-        raise NotImplementedError("Index-based message retrieval is only supported for single-channel traces.")
+        raise NotImplementedError(
+            "Index-based message retrieval is only supported for single-channel traces."
+        )
 
     def get_available_topics(self):
         return self.reader.get_available_topics()
-    
+
     def get_file_metadata(self):
         return self.reader.get_file_metadata()
-    
+
     def get_channel_metadata(self):
         return self.reader.get_channel_metadata()
 
 
 class _ReaderBase(ABC):
     """Common interface for trace readers"""
-    
+
     @abstractmethod
     def restart(self, index=None):
         pass
-    
+
     @abstractmethod
     def __iter__(self):
         pass
@@ -204,7 +232,7 @@ def get_channel_metadata(self):
 
 class _OSITraceSingle(_ReaderBase):
     """OSI single-channel trace reader"""
-    
+
     def __init__(self, path=None, type_name="SensorView", cache_messages=False):
         self.type = OSITrace.map_message_type(type_name)
         self.file = None
@@ -344,13 +372,19 @@ def close(self):
         self.type = None
 
     def get_available_topics(self):
-        raise NotImplementedError("Getting available topics is only supported for multi-channel traces.")
+        raise NotImplementedError(
+            "Getting available topics is only supported for multi-channel traces."
+        )
 
     def get_file_metadata(self):
-        raise NotImplementedError("Getting file metadata is only supported for multi-channel traces.")
+        raise NotImplementedError(
+            "Getting file metadata is only supported for multi-channel traces."
+        )
 
     def get_channel_metadata(self):
-        raise NotImplementedError("Getting channel metadata is only supported for multi-channel traces.")
+        raise NotImplementedError(
+            "Getting channel metadata is only supported for multi-channel traces."
+        )
 
 
 class _OSITraceMulti(_ReaderBase):
@@ -365,12 +399,16 @@ def __init__(self, path, type_name, topic):
         if topic == None:
             topic = next(iter(available_topics), None)
         if topic not in available_topics:
-            raise ValueError(f"The requested topic '{topic}' is not present in the trace file or is not of type '{type_name}'.")
+            raise ValueError(
+                f"The requested topic '{topic}' is not present in the trace file or is not of type '{type_name}'."
+            )
         self.topic = topic
-    
+
     def restart(self, index=None):
         if index != None:
-            raise NotImplementedError("Restarting from a given index is not supported for multi-channel traces.")
+            raise NotImplementedError(
+                "Restarting from a given index is not supported for multi-channel traces."
+            )
         self._iter = None
 
     def __iter__(self):
@@ -384,7 +422,7 @@ def __iter__(self):
             msg = message_class()
             msg.ParseFromString(message.data)
             yield msg
-    
+
     def close(self):
         if self._file:
             self._file.close()
@@ -393,8 +431,12 @@ def close(self):
         self._summary = None
         self._iter = None
 
-    def get_available_topics(self, type_name = None):
-        return [channel.topic for channel in self._summary.channels.values() if self._channel_is_of_type(channel, type_name)]
+    def get_available_topics(self, type_name=None):
+        return [
+            channel.topic
+            for channel in self._summary.channels.values()
+            if self._channel_is_of_type(channel, type_name)
+        ]
 
     def get_file_metadata(self):
         metadata = []
@@ -415,9 +457,11 @@ def get_message_type(self):
                 if schema.name.startswith("osi3."):
                     return schema.name[len("osi3.") :]
                 else:
-                    raise ValueError(f"Schema '{schema.name}' is not an 'osi3.' schema.")
+                    raise ValueError(
+                        f"Schema '{schema.name}' is not an 'osi3.' schema."
+                    )
         return None
 
     def _channel_is_of_type(self, channel, type_name):
-        schema = self._summary.schemas[channel.schema_id]  
+        schema = self._summary.schemas[channel.schema_id]
         return type_name is None or schema.name == f"osi3.{type_name}"