From 86ec99ede58da518ced7d3fbfba02d841e72ce04 Mon Sep 17 00:00:00 2001
From: Nicolas Hug <nicolashug@meta.com>
Date: Tue, 11 Nov 2025 15:56:20 +0000
Subject: [PATCH 1/2] Simplify seek skipping logic

---
 src/torchcodec/_core/SingleStreamDecoder.cpp | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/torchcodec/_core/SingleStreamDecoder.cpp b/src/torchcodec/_core/SingleStreamDecoder.cpp
index 4a81c9a8f..b6cdf055b 100644
--- a/src/torchcodec/_core/SingleStreamDecoder.cpp
+++ b/src/torchcodec/_core/SingleStreamDecoder.cpp
@@ -1100,6 +1100,9 @@ I    P     P    P    I    P    P    P    I    P    P    I    P    P    I    P
 */
 bool SingleStreamDecoder::canWeAvoidSeeking() const {
   const StreamInfo& streamInfo = streamInfos_.at(activeStreamIndex_);
+  if (!cursorWasJustSet_) {
+    return true;
+  }
   if (streamInfo.avMediaType == AVMEDIA_TYPE_AUDIO) {
     // For audio, we only need to seek if a backwards seek was requested
     // within getFramesPlayedInRangeAudio(), when setCursorPtsInSeconds() was
@@ -1181,10 +1184,8 @@ UniqueAVFrame SingleStreamDecoder::decodeAVFrame(
 
   resetDecodeStats();
 
-  if (cursorWasJustSet_) {
-    maybeSeekToBeforeDesiredPts();
-    cursorWasJustSet_ = false;
-  }
+  maybeSeekToBeforeDesiredPts();
+  cursorWasJustSet_ = false;
 
   UniqueAVFrame avFrame(av_frame_alloc());
   AutoAVPacket autoAVPacket;

From abc2cb1e3d4b06f326612a4bd7e0d0c4947d5173 Mon Sep 17 00:00:00 2001
From: Nicolas Hug <nicolashug@meta.com>
Date: Tue, 11 Nov 2025 18:49:55 +0000
Subject: [PATCH 2/2] Minor change

---
 src/torchcodec/_core/SingleStreamDecoder.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/torchcodec/_core/SingleStreamDecoder.cpp b/src/torchcodec/_core/SingleStreamDecoder.cpp
index b6cdf055b..0097f278d 100644
--- a/src/torchcodec/_core/SingleStreamDecoder.cpp
+++ b/src/torchcodec/_core/SingleStreamDecoder.cpp
@@ -1100,15 +1100,16 @@ I    P     P    P    I    P    P    P    I    P    P    I    P    P    I    P
 */
 bool SingleStreamDecoder::canWeAvoidSeeking() const {
   const StreamInfo& streamInfo = streamInfos_.at(activeStreamIndex_);
-  if (!cursorWasJustSet_) {
-    return true;
-  }
   if (streamInfo.avMediaType == AVMEDIA_TYPE_AUDIO) {
     // For audio, we only need to seek if a backwards seek was requested
     // within getFramesPlayedInRangeAudio(), when setCursorPtsInSeconds() was
     // called. For more context, see [Audio Decoding Design]
     return !cursorWasJustSet_;
+  } else if (!cursorWasJustSet_) {
+    // For videos, when decoding consecutive frames, we don't need to seek.
+    return true;
   }
+
   if (cursor_ < lastDecodedAvFramePts_) {
     // We can never skip a seek if we are seeking backwards.
     return false;