From 6354eb29ed2ed5321509fefcfdbc793bb3aaf16f Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:02:14 +0100
Subject: [PATCH 01/12] Draw a red point if a survey failed. Remove failed
 points when starting a new survey.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 wifi_survey_heatmap/ui.py | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/wifi_survey_heatmap/ui.py b/wifi_survey_heatmap/ui.py
index dc6d69a..80e8394 100644
--- a/wifi_survey_heatmap/ui.py
+++ b/wifi_survey_heatmap/ui.py
@@ -119,6 +119,7 @@ def set_progress(self, value, total):
 
     def set_is_finished(self):
         self.is_finished = True
+        self.is_failed = False
         self.progress = 100
 
     def draw(self, dc, color=None):
@@ -334,9 +335,17 @@ def _check_bssid(self):
         self.warn(msg)
         return False
 
+    def _abort(self, reason):
+        self.survey_points[-1].set_is_failed()
+        self.parent.SetStatusText('Aborted: {}'.format(reason))
+        self.Refresh()
+
     def _do_measurement(self, pos):
-        self.parent.SetStatusText('Got click at: %s' % pos)
+        self.parent.SetStatusText('Starting survey...')
+        # Add new survey point
         self.survey_points.append(SurveyPoint(self, pos[0], pos[1]))
+        # Delete failed survey points
+        self.survey_points = [p for p in self.survey_points if not p.is_failed]
         self.Refresh()
         res = {}
         count = 0
@@ -345,9 +354,11 @@ def _do_measurement(self, pos):
         # Check if we are connected to an AP, all the
         # rest doesn't any sense otherwise
         if not self.collector.check_associated():
+            self._abort("Not connected to an access point")
             return
         # Check BSSID
         if not self._check_bssid():
+            self._abort("BSSID check failed")
             return
 
         # Skip iperf test if empty server string was given
@@ -360,15 +371,14 @@ def _do_measurement(self, pos):
 
                     # Check if we're still connected to the same AP
                     if not self._check_bssid():
+                        self._abort("BSSID check failed")
                         return
 
                     # Start iperf test
                     tmp = self.run_iperf(count, udp, reverse)
                     if tmp is None:
                         # bail out; abort this survey point
-                        del self.survey_points[-1]
-                        self.parent.SetStatusText('Aborted; ready to retry...')
-                        self.Refresh()
+                        self._abort("iperf test failed")
                         return
                     # else success
                     res['%s%s' % (protoname, suffix)] = {
@@ -377,7 +387,7 @@ def _do_measurement(self, pos):
 
         # Check if we're still connected to the same AP
         if not self._check_bssid():
-            del self.survey_points[-1]
+            self._abort("BSSID check failed")
             return
 
         # Get all signal metrics from nl

From 09af720312b03ec3ce1574b21a034e1d2e8a1d0d Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:03:04 +0100
Subject: [PATCH 02/12] Do not start maximized. This makes sense now that we
 support image scaling.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 wifi_survey_heatmap/ui.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/wifi_survey_heatmap/ui.py b/wifi_survey_heatmap/ui.py
index 80e8394..04107a6 100644
--- a/wifi_survey_heatmap/ui.py
+++ b/wifi_survey_heatmap/ui.py
@@ -598,7 +598,6 @@ def main():
         title='wifi-survey: %s' % args.TITLE,
     )
     frm.Show()
-    frm.Maximize(True)
     frm.SetStatusText('%s' % frm.pnl.GetSize())
     app.MainLoop()
 

From e9dcde570a8026e435e743dc0566df9b5d20a925 Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:06:44 +0100
Subject: [PATCH 03/12] Change color of moving point from red to lightblue as
 we're now using red to indicate failure.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 wifi_survey_heatmap/ui.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/wifi_survey_heatmap/ui.py b/wifi_survey_heatmap/ui.py
index 04107a6..cd95229 100644
--- a/wifi_survey_heatmap/ui.py
+++ b/wifi_survey_heatmap/ui.py
@@ -283,7 +283,7 @@ def onLeftDown(self, event):
         self._moving_point = point
         self._moving_x = point.x
         self._moving_y = point.y
-        point.draw(wx.ClientDC(self), color='blue')
+        point.draw(wx.ClientDC(self), color='lightblue')
 
     def onLeftUp(self, event):
         x, y = pos = self.get_xy(event)
@@ -294,9 +294,9 @@ def onLeftUp(self, event):
         oldy = self._moving_point.y
         self._moving_point.x = x
         self._moving_point.y = y
-        self._moving_point.draw(wx.ClientDC(self), color='red')
+        self._moving_point.draw(wx.ClientDC(self), color='lightblue')
         res = self.YesNo(
-            f'Move point from blue ({oldx}, {oldy}) to red ({x}, {y})?'
+            f'Move point from ({oldx}, {oldy}) to ({x}, {y})?'
         )
         if not res:
             self._moving_point.x = self._moving_x
@@ -315,7 +315,7 @@ def onMotion(self, event):
         self._moving_point.erase(dc)
         self._moving_point.x = x
         self._moving_point.y = y
-        self._moving_point.draw(dc, color='red')
+        self._moving_point.draw(dc, color='lightblue')
 
     def _check_bssid(self):
         # Return early if BSSID is not to be verified

From ab44db2ad042eb32feb9d33632f9d3293a3467e8 Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:10:11 +0100
Subject: [PATCH 04/12] Make SERVER an optional property to easily skip iperf3
 tests in case there is no suitable server. Also disable scanning by default
 as it takes quite some time and does not give all that much information in
 the end. Finally, update the README to reflect these changes

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 README.rst                | 24 ++++++++++++------------
 wifi_survey_heatmap/ui.py | 21 +++++++++++----------
 2 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/README.rst b/README.rst
index f6944cf..c8cd3af 100644
--- a/README.rst
+++ b/README.rst
@@ -20,7 +20,7 @@ Quick start
 
 Check out the **Running In Docker** steps below to get single-line commands that run without the need to install *anything* on your computer (thanks to using `docker`).
 Creating a heatmap using the software consists of the following three essential steps:
-1. Start an `iperf3` server on any machine in your local network. This server is used for bandwidth measurements to be independent of your Internet connection.
+1. Start an `iperf3` server on any machine in your local network. This server is used for bandwidth measurements to be independent of your Internet connection. When omitting the `--server` option, this may be skipped, however, be aware that the performance heatmaps tpyically are the icing on the cake of your measurement and are very useful in determining the *real* performance of your WiFi.
 2. Use the `wifi-survey` tool to record a measurement. You can load a floorplan and click on your current location ot record signal strength and determine the achievable bandwidth.
 3. Once done with all the measurements, use the `wifi-heatmap` tool to compute a high-resolution heatmap from your recorded data. In case your data turns out to be too coarse, you can always go back to step 2 and delete or move old and also add new measurements at any time.
 
@@ -32,7 +32,7 @@ Installation and Dependencies
 * The Python `iperf3 <https://pypi.org/project/iperf3/>`_ package, which needs `iperf3 <http://software.es.net/iperf/>`_ installed on your system.
 * The Python `libiw <https://pypi.org/project/libiw/>`_ package.
 * `wxPython Phoenix <https://wiki.wxpython.org/How%20to%20install%20wxPython>`_, which unfortunately must be installed using OS packages or built from source.
-* An iperf3 server running on another system on the LAN, as described below.
+* An iperf3 server running on another system on the LAN, as described below is recommended but optional.
 
 Recommended installation is via ``python setup.py develop`` in a virtualenv setup with ``--system-site-packages`` (for the above dependencies).
 
@@ -43,15 +43,15 @@ Data Collection
 
 At each survey location, data collection should take 45-60 seconds. The data collected is currently:
 
-* 10-second iperf3 measurement, TCP, client (this app) sending to server, default iperf3 options
-* 10-second iperf3 measurement, TCP, server sending to client, default iperf3 options
-* 10-second iperf3 measurement, UDP, client (this app) sending to server, default iperf3 options
+* 10-second iperf3 measurement, TCP, client (this app) sending to server, default iperf3 options [optional, enable with `--server`]
+* 10-second iperf3 measurement, TCP, server sending to client, default iperf3 options [optional, enable with `--server`]
+* 10-second iperf3 measurement, UDP, client (this app) sending to server, default iperf3 options [optional, enable with `--server`]
 * Recording of various WiFi details such as advertised channel bandwidth, bitrate, or signal strength
-* Scan of all visible access points in the vicinity
+* Scan of all visible access points in the vicinity [optional, enable with `--scan`]
 
 Hints:
 - The duration of the bandwidth measurement can be changed using the `--duration` argument of `wifi-survey`. This has great influence on the actual length of the individual data collections.
-- Scanning for other network takes rather long. As this isn't required in most cases, you can skip this using `wifi-survey --no-scan`
+- Scanning for other network takes rather long. As this isn't required in most cases, it is not enabled by default
 
 Usage
 -----
@@ -68,10 +68,9 @@ Performing a Survey
 
 The survey tool (``wifi-survey``) must be run as root or via ``sudo`` in order to use iwconfig/iwlist.
 
-First connect to the network that you want to survey. Then, run ``sudo wifi-survey INTERFACE SERVER PNG Title`` where:
+First connect to the network that you want to survey. Then, run ``sudo wifi-survey INTERFACE PNG Title`` where:
 
 * ``INTERFACE`` is the name of your Wireless interface (e.g. ``wlp3s0``)
-* ``SERVER`` is the IP address or hostname of the iperf3 server
 * ``PNG`` is the path to a floorplan PNG file to use as the background for the map; see `examples/example_floorplan.png <examples/example_floorplan.png>`_ for an example. In order to compare multiple surveys it may be helpful to pre-mark your measurement points on the floorplan, like `examples/example_with_marks.png <examples/example_with_marks.png`_. The UI currently loads the PNG at exact size, so it may help to scale your PNG file to your display.
 * ``Title`` is the title for the survey (such as the network name or AP location), which will also be used to name the data file and output files.
 
@@ -79,8 +78,9 @@ If ``Title.json`` already exists, the data from it will be pre-loaded into the a
 
 Some other command-line options include:
 
-* ``-S`` / ``--no-scan`` to disable running iwlist scans at the end of each measurement. This greatly speeds up survey time but loses the data used for channel utilization graphs. If you're using a modern wireless product that allows running RF scans, it makes sense to use that data instead of iw scans.
-* ``-b`` / ``--bssid`` allows you to specify a single desired BSSID for your survey. This will be checked several times during of every measurement, and the measurement will be discarded if you're connected to the wrong BSSID. This can be useful as a safeguard to make sure you don't accidentally roam to a different AP.
+* ``-s`` / ``--server IPERF3_SERVER`` to enable ``iperf3`` scans. The generated speed heatmaps are very useful (much more useful than signal strength) in visualizing the *real* performance of your network as they are live measurements with real data (instead of only theoretical values).
+* ``-S`` / ``--scan`` to enable wireless scaning at the end of each measurement. This may take a lot of time, however, generates data used later for generating channel utilization graphs. If you're using a modern wireless product that allows running RF scans, it makes sense to use that data instead of these scans.
+* ``-b`` / ``--bssid BSSID`` allows you to specify a single desired BSSID for your survey. This will be checked several times during of every measurement, and the measurement will be discarded if you're connected to the wrong BSSID. This can be useful as a safeguard to make sure you don't accidentally roam to a different AP.
 * ``-d`` / ``--duration`` allows you to change the duration of each individual `iperf3` test run (default is 10 seconds as mentioned above)
 
 When the UI loads, you should see your PNG file displayed. The UI is really simple:
@@ -153,7 +153,7 @@ Survey
      -e DISPLAY=$DISPLAY \
      -v "$HOME/.Xauthority:/root/.Xauthority:ro" \
      jantman/python-wifi-survey-heatmap \
-     wifi-survey INTERFACE SERVER FLOORPLAN.png TITLE
+     wifi-survey INTERFACE FLOORPLAN.png TITLE
 
 Note that running with ``--net="host"`` and ``--privileged`` is required in order to manipulate the host's wireless interface.
 
diff --git a/wifi_survey_heatmap/ui.py b/wifi_survey_heatmap/ui.py
index cd95229..045fab6 100644
--- a/wifi_survey_heatmap/ui.py
+++ b/wifi_survey_heatmap/ui.py
@@ -362,7 +362,7 @@ def _do_measurement(self, pos):
             return
 
         # Skip iperf test if empty server string was given
-        if len(self.collector._iperf_server) > 0:
+        if self.collector._iperf_server is not None:
             for protoname, udp in {'tcp': False, 'udp': True}.items():
                 for suffix, reverse in {'': False, '-reverse': True}.items():
                     # Update progress mark
@@ -525,9 +525,14 @@ def parse_args(argv):
     p = argparse.ArgumentParser(description='wifi survey data collection UI')
     p.add_argument('-v', '--verbose', dest='verbose', action='count', default=0,
                    help='verbose output. specify twice for debug-level output.')
-    p.add_argument('-S', '--no-scan', dest='scan', action='store_false',
-                   default=True, help='skip access point scan')
-    p.add_argument('-b', '--bssid', dest='bssid', action='store', type=str,
+    p.add_argument('-S', '--scan', dest='scan', action='store_true',
+                   default=False, help='Scan for access points in the vicinity')
+    p.add_argument('-s', '--server', dest='IPERF3_SERVER', action='store', type=str,
+                   default=None, help='iperf3 server IP or hostname')
+    p.add_argument('-d', '--duration', dest='IPERF3_DURATION', action='store',
+                   type=int, default=10,
+                   help='Duration of each individual ipref3 test run')
+    p.add_argument('-b', '--bssid', dest='BSSID', action='store', type=str,
                    default=None, help='Restrict survey to this BSSID')
     p.add_argument('--ding', dest='ding', action='store', type=str,
                    default=None,
@@ -535,11 +540,7 @@ def parse_args(argv):
     p.add_argument('--ding-command', dest='ding_command', action='store',
                    type=str, default='/usr/bin/paplay',
                    help='Path to ding command')
-    p.add_argument('-d', '--duration', dest='duration', action='store',
-                   type=int, default=10,
-                   help='Duration of each individual ipref test run')
     p.add_argument('INTERFACE', type=str, help='Wireless interface name')
-    p.add_argument('SERVER', type=str, help='iperf3 server IP or hostname')
     p.add_argument('IMAGE', type=str, help='Path to background image')
     p.add_argument(
         'TITLE', type=str, help='Title for survey (and data filename)'
@@ -593,8 +594,8 @@ def main():
 
     app = wx.App()
     frm = MainFrame(
-        args.IMAGE, args.INTERFACE, args.SERVER, args.TITLE, args.scan,
-        args.bssid, args.ding, args.ding_command, args.duration, None,
+        args.IMAGE, args.INTERFACE, args.IPERF3_SERVER, args.TITLE, args.scan,
+        args.BSSID, args.ding, args.ding_command, args.IPERF3_DURATION, None,
         title='wifi-survey: %s' % args.TITLE,
     )
     frm.Show()

From aa49de1c28829a0ead6cc80fbb7bcca18ef91941 Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:16:51 +0100
Subject: [PATCH 05/12] Add frequency graph and differentiate

between upload and download UDP jitter.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 README.rst                     | 10 ++++++----
 wifi_survey_heatmap/heatmap.py | 36 ++++++++++++++++++++++------------
 2 files changed, 29 insertions(+), 17 deletions(-)

diff --git a/README.rst b/README.rst
index c8cd3af..a48981c 100644
--- a/README.rst
+++ b/README.rst
@@ -121,14 +121,16 @@ The end result of this process for a given survey (Title) should be some ``.png`
 
 * `channels24_TITLE.png` - Bar graph of average signal quality of APs seen on 2.4 GHz channels, by channel. Useful for visualizing channel contention. (Based on 20 MHz channel bandwidth)
 * `channels5_TITLE.png` - Bar graph of average signal quality of APs seen on 5 GHz channels, by channel. Useful for visualizing channel contention. (Based on per-channel bandwidth from 20 to 160 MHz)
-* `jitter_TITLE.png` - Heatmap based on UDP jitter measurement in milliseconds.
-* `rss_TITLE.png` - Heatmap based on the received signal strength.
+* `signal_quality_TITLE.png` - Heatmap based on the received signal strength.
+* `tx_power_TITLE.png` - Heatmap based on the transmitter power your WiFi card used. If your WiFi card doe snot support adaptive power management, this number will stay constant.
 * `tcp_download_Mbps_TITLE.png` - Heatmap of `iperf3` transfer rate, TCP, downloading from server to client.
 * `tcp_upload_Mbps_TITLE.png` - Heatmap of `iperf3` transfer rate, TCP, uploading from client to server.
+* `udp_download_Mbps_TITLE.png` - Heatmap of `iperf3` transfer rate, UDP, downloading from server to client.
 * `udp_upload_Mbps_TITLE.png` - Heatmap of `iperf3` transfer rate, UDP, uploading from client to server.
+* `jitter_download_TITLE.png` - Heatmap based on UDP jitter measurement in milliseconds.
+* `jitter_upload_TITLE.png` - Heatmap based on UDP jitter measurement in milliseconds.
 * `frequency_TITLE.png` - Heatmap of used frequency. May reveal zones in which Wi-Fi steering moved the device onto a different band (2.4GHz / 5 GHz co-existance).
-* `channel_rx_bitrate_TITLE.png` - Heatmap of advertised channel bandwidth in RX direction (AP to client)
-* `channel_tx_bitrate_TITLE.png` - Heatmap of advertised channel bandwidth in TX direction (client to AP)
+* `channel_bitrate_TITLE.png` - Heatmap of negotiated channel bandwidth
 
 If you'd like to synchronize the colors/thresholds across multiple heatmaps, such as when comparing different AP placements, you can run ``wifi-heatmap-thresholds`` passing it each of the titles / output JSON filenames. This will generate a ``thresholds.json`` file in the current directory, suitable for passing to the ``wifi-heatmap`` ``-t`` / ``--thresholds`` option.
 
diff --git a/wifi_survey_heatmap/heatmap.py b/wifi_survey_heatmap/heatmap.py
index 116c37c..78cee04 100644
--- a/wifi_survey_heatmap/heatmap.py
+++ b/wifi_survey_heatmap/heatmap.py
@@ -136,10 +136,11 @@ class HeatMapGenerator(object):
         'udp_download_Mbps': 'Download (UDP) [MBit/s]',
         'tcp_upload_Mbps': 'Upload (TCP) [MBit/s]',
         'udp_upload_Mbps': 'Upload (UDP) [MBit/s]',
-        'jitter': 'UDP Jitter [ms]',
+        'jitter_download': 'UDP Download Jitter [ms]',
+        'jitter_upload': 'UDP Upload Jitter [ms]',
+        'frequency': 'Wi-Fi frequency [GHz]',
         'channel': 'Wi-Fi channel',
         'channel_bitrate': 'Maximum channel bandwidth [MBit/s]',
-
     }
 
     def __init__(
@@ -183,18 +184,24 @@ def load_data(self):
             a['x'].append(row['x'])
             a['y'].append(row['y'])
             a['channel'].append(row['result']['channel'])
-            a['tcp_upload_Mbps'].append(
-                row['result']['tcp']['received_Mbps']
-            )
-            a['tcp_download_Mbps'].append(
-                row['result']['tcp-reverse']['received_Mbps']
-            )
-            a['udp_download_Mbps'].append(row['result']['udp']['Mbps'])
-            a['udp_upload_Mbps'].append(row['result']['udp-reverse']['Mbps'])
-            a['jitter'].append(row['result']['udp']['jitter_ms'])
+            if 'tcp' in row['result']:
+                a['tcp_upload_Mbps'].append(
+                    row['result']['tcp']['received_Mbps']
+                )
+            if 'tcp-reverse' in row['result']:
+                a['tcp_download_Mbps'].append(
+                    row['result']['tcp-reverse']['received_Mbps']
+                )
+            if 'udp' in row['result']:
+                a['udp_download_Mbps'].append(row['result']['udp']['Mbps'])
+                a['jitter_download'].append(row['result']['udp']['jitter_ms'])
+            if 'udp-reverse' in row['result']:
+                a['udp_upload_Mbps'].append(row['result']['udp-reverse']['Mbps'])
+                a['jitter_upload'].append(row['result']['udp-reverse']['jitter_ms'])
             a['tx_power'].append(row['result']['tx_power'])
-            a['frequency'].append(row['result']['frequency'])
-            a['channel_bitrate'].append(row['result']['bitrate'])
+            a['frequency'].append(row['result']['frequency']*1e-3)
+            if 'bitrate' in row['result']:
+                a['channel_bitrate'].append(row['result']['bitrate'])
             a['signal_quality'].append(row['result']['signal_mbm']+130)
             ap = self._ap_names.get(
                 row['result']['ssid'].upper(),
@@ -338,6 +345,9 @@ def _add_inner_title(self, ax, title, loc, size=None, **kwargs):
         return at
 
     def _plot(self, a, key, title, gx, gy, num_x, num_y):
+        if key not in a:
+            logger.info("Skipping {} due to insufficient data".format(key))
+            return
         logger.debug('Plotting: %s', key)
         pp.rcParams['figure.figsize'] = (
             self._image_width / 300, self._image_height / 300

From 7258a416fdc46a6dd166972fc6281e3973cd3f96 Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:19:55 +0100
Subject: [PATCH 06/12] Update Dockerfile to use patched version of libnl

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 Dockerfile | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index fb67fb7..b125740 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -6,22 +6,26 @@ ARG repo_ref
 USER root
 
 RUN apt-get update && \
-  DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
+  DEBIAN_FRONTEND=noninteractive \
+  apt-get install -y --no-install-recommends \
     iperf3 \
     gcc \
     git \
     pulseaudio-utils \
     python3 \
     python3-dev \
-    python3-matplotlib \
     python3-pip \
-    python3-scipy \
     python3-setuptools \
-    python3-wheel \
     python3-wxgtk4.0 \
-    wireless-tools && \
-  pip3 install \
-    iperf3
+    wireless-tools \
+  && rm -rf /var/lib/apt/lists/*
+
+RUN pip3 install iperf3 matplotlib scipy wheel
+
+# Install libnl from DL6ER's fork because the python3.6+
+# compatibility fixes weren't included in the upstream
+# project in 12/2020
+RUN pip3 install --upgrade --user git+https://github.com/DL6ER/libnl
 
 COPY . /app
 

From 98c1a014cfa0adf489d9642c0a04cf4e55c32195 Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:37:55 +0100
Subject: [PATCH 07/12] Allow starting wifi-survey without any mandatory
 arguments. Missing items will be asked for in an interactive manner.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 README.rst                       |  23 ++++---
 wifi_survey_heatmap/collector.py |   8 +--
 wifi_survey_heatmap/libnl.py     |  31 +++++----
 wifi_survey_heatmap/ui.py        | 105 +++++++++++++++++++++++++++----
 4 files changed, 126 insertions(+), 41 deletions(-)

diff --git a/README.rst b/README.rst
index a48981c..429c7cf 100644
--- a/README.rst
+++ b/README.rst
@@ -68,20 +68,19 @@ Performing a Survey
 
 The survey tool (``wifi-survey``) must be run as root or via ``sudo`` in order to use iwconfig/iwlist.
 
-First connect to the network that you want to survey. Then, run ``sudo wifi-survey INTERFACE PNG Title`` where:
+First connect to the network that you want to survey. Then, run ``sudo wifi-survey`` where:
 
-* ``INTERFACE`` is the name of your Wireless interface (e.g. ``wlp3s0``)
-* ``PNG`` is the path to a floorplan PNG file to use as the background for the map; see `examples/example_floorplan.png <examples/example_floorplan.png>`_ for an example. In order to compare multiple surveys it may be helpful to pre-mark your measurement points on the floorplan, like `examples/example_with_marks.png <examples/example_with_marks.png`_. The UI currently loads the PNG at exact size, so it may help to scale your PNG file to your display.
-* ``Title`` is the title for the survey (such as the network name or AP location), which will also be used to name the data file and output files.
+Command-line options include:
 
-If ``Title.json`` already exists, the data from it will be pre-loaded into the application; this can be used to resume a survey.
-
-Some other command-line options include:
-
-* ``-s`` / ``--server IPERF3_SERVER`` to enable ``iperf3`` scans. The generated speed heatmaps are very useful (much more useful than signal strength) in visualizing the *real* performance of your network as they are live measurements with real data (instead of only theoretical values).
+* ``-i INTERFACE`` / ``--interface INTERFACE`` is the name of your Wireless interface (e.g. ``wlp3s0``)
+* ``-p PICTURE`` / ``--picture PICTURE`` is the path to a floorplan PNG file to use as the background for the map; see `examples/example_floorplan.png <examples/example_floorplan.png>`_ for an example. In order to compare multiple surveys it may be helpful to pre-mark your measurement points on the floorplan, like `examples/example_with_marks.png <examples/example_with_marks.png`_. The UI currently loads the PNG at exact size, so it may help to scale your PNG file to your display.
+* ``-t TITLE`` / ``--title TITLE`` is the title for the survey (such as the network name or AP location), which will also be used to name the data file and output files.
+* ``-s IPERF3_SERVER`` / ``--server IPERF3_SERVER`` to enable ``iperf3`` scans. The generated speed heatmaps are very useful (much more useful than signal strength) in visualizing the *real* performance of your network as they are live measurements with real data (instead of only theoretical values).
 * ``-S`` / ``--scan`` to enable wireless scaning at the end of each measurement. This may take a lot of time, however, generates data used later for generating channel utilization graphs. If you're using a modern wireless product that allows running RF scans, it makes sense to use that data instead of these scans.
-* ``-b`` / ``--bssid BSSID`` allows you to specify a single desired BSSID for your survey. This will be checked several times during of every measurement, and the measurement will be discarded if you're connected to the wrong BSSID. This can be useful as a safeguard to make sure you don't accidentally roam to a different AP.
-* ``-d`` / ``--duration`` allows you to change the duration of each individual `iperf3` test run (default is 10 seconds as mentioned above)
+* ``-b BSSID`` / ``--bssid BSSID`` allows you to specify a single desired BSSID for your survey. This will be checked several times during of every measurement, and the measurement will be discarded if you're connected to the wrong BSSID. This can be useful as a safeguard to make sure you don't accidentally roam to a different AP.
+* ``-d 123`` / ``--duration 123`` allows you to change the duration of each individual `iperf3` test run (default is 10 seconds as mentioned above)
+
+If ``TITLE.json`` already exists, the data from it will be pre-loaded into the application; this can be used to **resume a survey**.
 
 When the UI loads, you should see your PNG file displayed. The UI is really simple:
 
@@ -155,7 +154,7 @@ Survey
      -e DISPLAY=$DISPLAY \
      -v "$HOME/.Xauthority:/root/.Xauthority:ro" \
      jantman/python-wifi-survey-heatmap \
-     wifi-survey INTERFACE FLOORPLAN.png TITLE
+     wifi-survey
 
 Note that running with ``--net="host"`` and ``--privileged`` is required in order to manipulate the host's wireless interface.
 
diff --git a/wifi_survey_heatmap/collector.py b/wifi_survey_heatmap/collector.py
index b12cf4c..6730fe0 100644
--- a/wifi_survey_heatmap/collector.py
+++ b/wifi_survey_heatmap/collector.py
@@ -47,19 +47,17 @@
 
 class Collector(object):
 
-    def __init__(self, interface_name, server_addr, duration, scan=True):
+    def __init__(self, server_addr, duration, scanner, scan=True):
         super().__init__()
         logger.debug(
             'Initializing Collector for interface: %s; iperf server: %s',
-            interface_name, server_addr
+            scanner.interface_name, server_addr
         )
         # ensure interface_name is a wireless interfaces
-        self._interface_name = interface_name
         self._iperf_server = server_addr
         self._scan = scan
         self._duration = duration
-
-        self.scanner = Scanner(interface_name, scan)
+        self.scanner = scanner
 
     def run_iperf(self, udp=False, reverse=False):
         client = iperf3.Client()
diff --git a/wifi_survey_heatmap/libnl.py b/wifi_survey_heatmap/libnl.py
index 5d42d62..355c435 100644
--- a/wifi_survey_heatmap/libnl.py
+++ b/wifi_survey_heatmap/libnl.py
@@ -73,13 +73,13 @@
 
 class Scanner(object):
 
-    def __init__(self, interface_name, scan=True):
+    def __init__(self, interface_name=None, scan=True):
         super().__init__()
         logger.debug(
             'Initializing Scanner for interface: %s',
             interface_name
         )
-        self._interface_name = interface_name
+        self.interface_name = interface_name
         self._scan = scan
         self.iface_data = {}
 
@@ -87,19 +87,26 @@ def __init__(self, interface_name, scan=True):
 
         # Get all interfaces of this machine
         self.if_idx = None
-        self.update_iface_details(nl80211.NL80211_CMD_GET_INTERFACE)
-        names = []
+        self.iface_names = self.list_all_interfaces()
+
+    def set_interface(self, interface_name):
         for idx in self.iface_data:
-            if 'name' in self.iface_data[idx]:
-                names.append(self.iface_data[idx]['name'])
-                if self.iface_data[idx]['name'] == interface_name:
-                    self.if_idx = idx
-                    break
+            if self.iface_data[idx]['name'] == interface_name:
+                self.if_idx = idx
+                break
         if self.if_idx == None:
             logger.error("Device {0} is not a valid interface, use"
-                         " one of {1}".format(interface_name, names))
+                        " one of {1}".format(interface_name, self.iface_names))
             exit(1)
 
+    def list_all_interfaces(self):
+        self.update_iface_details(nl80211.NL80211_CMD_GET_INTERFACE)
+        iface_names = []
+        for idx in self.iface_data:
+            if 'name' in self.iface_data[idx]:
+                iface_names.append(self.iface_data[idx]['name'])
+        return iface_names
+
     def _error_handler(self, _, err, arg):
         """Update the mutable integer `arg` with the error code."""
         arg.value = err.error
@@ -289,7 +296,7 @@ def scan_all_access_points(self):
         # Scan for access points within reach
 
         # First get the wireless interface index.
-        pack = struct.pack('16sI', self._interface_name.encode('ascii'), 0)
+        pack = struct.pack('16sI', self.interface_name.encode('ascii'), 0)
         sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
         try:
             info = struct.unpack('16sI', fcntl.ioctl(
@@ -297,7 +304,7 @@ def scan_all_access_points(self):
         except OSError:
             return logger.warning(
                 'Wireless interface {0}\
-                    does not exist.'.format(self._interface_name))
+                    does not exist.'.format(self.interface_name))
         finally:
             sock.close()
         if_index = int(info[1])
diff --git a/wifi_survey_heatmap/ui.py b/wifi_survey_heatmap/ui.py
index 045fab6..e260ef3 100644
--- a/wifi_survey_heatmap/ui.py
+++ b/wifi_survey_heatmap/ui.py
@@ -44,6 +44,7 @@
 import subprocess
 
 from wifi_survey_heatmap.collector import Collector
+from wifi_survey_heatmap.libnl import Scanner
 
 FORMAT = "[%(asctime)s %(levelname)s] %(message)s"
 logging.basicConfig(level=logging.WARNING, format=FORMAT)
@@ -193,7 +194,7 @@ def __init__(self, parent):
             self._load_file(self.data_filename)
         self._duration = self.parent.duration
         self.collector = Collector(
-            self.parent.interface, self.parent.server, self._duration)
+            self.parent.server, self._duration, self.parent.scanner)
         self.parent.SetStatusText("Ready.")
 
     def _load_file(self, fpath):
@@ -482,12 +483,11 @@ def on_paint(self, event=None):
 class MainFrame(wx.Frame):
 
     def __init__(
-            self, img_path, interface, server, survey_title, scan, bssid, ding,
-            ding_command, duration, *args, **kw
+            self, img_path, server, survey_title, scan, bssid, ding,
+            ding_command, duration, scanner, *args, **kw
     ):
         super(MainFrame, self).__init__(*args, **kw)
         self.img_path = img_path
-        self.interface = interface
         self.server = server
         self.scan = scan
         self.survey_title = survey_title
@@ -498,6 +498,7 @@ def __init__(
         self.ding_command = ding_command
         self.duration = duration
         self.CreateStatusBar()
+        self.scanner = scanner
         self.pnl = FloorplanPanel(self)
         self.makeMenuBar()
 
@@ -540,11 +541,14 @@ def parse_args(argv):
     p.add_argument('--ding-command', dest='ding_command', action='store',
                    type=str, default='/usr/bin/paplay',
                    help='Path to ding command')
-    p.add_argument('INTERFACE', type=str, help='Wireless interface name')
-    p.add_argument('IMAGE', type=str, help='Path to background image')
-    p.add_argument(
-        'TITLE', type=str, help='Title for survey (and data filename)'
-    )
+    p.add_argument('-i', '--interface', dest='INTERFACE', action='store',
+                   type=str, default=None,
+                   help='Wireless interface name')
+    p.add_argument('-p', '--picture', dest='IMAGE', type=str,
+                   default=None, help='Path to background image')
+    p.add_argument('-t', '--title', dest='TITLE', type=str,
+                   default=None, help='Title for survey (and data filename)'
+                   )
     args = p.parse_args(argv)
     return args
 
@@ -578,6 +582,58 @@ def set_log_level_format(level, format):
     logger.setLevel(level)
 
 
+def ask_for_wifi_iface(app, scanner):
+    frame = wx.Frame(None)
+    title = 'Wireless interface'
+    description = 'Please specify the wireless interface\nto be used for your survey'
+    dlg = wx.SingleChoiceDialog(frame, description, title, scanner.iface_names)
+    if dlg.ShowModal() == wx.ID_OK:
+        resu = dlg.GetStringSelection()
+    else:
+        # User clicked [Cancel]
+        exit()
+    dlg.Destroy()
+    frame.Destroy()
+
+    return resu
+
+
+def ask_for_title(app):
+    frame = wx.Frame(None)
+    title = 'Title of your measurement'
+    description = 'Please specify a title for your measurement. This title will be used to store the results and to distinguish the generated plots'
+    default = 'Example'
+    dlg = wx.TextEntryDialog(frame, description, title)
+    dlg.SetValue(default)
+    if dlg.ShowModal() == wx.ID_OK:
+        resu = dlg.GetValue()
+    else:
+        # User clicked [Cancel]
+        exit()
+    dlg.Destroy()
+    frame.Destroy()
+
+    return resu
+
+
+def ask_for_floorplan(app):
+    frame = wx.Frame(None)
+    title = 'Select floorplan for your measurement'
+    dlg = wx.FileDialog(frame, title,
+                        wildcard='Compatible image files (*.png, *.jpg,*.tiff, *.bmp)|*.png;*.jpg;*.tiff;*.bmp;*:PNG;*.JPG;*.TIFF;*.BMP;*.jpeg;*.JPEG',
+                        style=wx.FD_FILE_MUST_EXIST)
+    if dlg.ShowModal() == wx.ID_OK:
+        resu = dlg.GetPath()
+        print(resu)
+    else:
+        # User clicked [Cancel]
+        exit()
+    dlg.Destroy()
+    frame.Destroy()
+
+    return resu
+
+
 def main():
     if os.getuid() != 0:
         logger.warning("You should run this script as root"
@@ -593,10 +649,35 @@ def main():
         set_log_info()
 
     app = wx.App()
+
+    scanner = Scanner(scan=args.scan)
+
+    # Ask for possibly missing fields
+    # Wireless interface
+    if args.INTERFACE is None:
+        INTERFACE = ask_for_wifi_iface(app, scanner)
+    else:
+        INTERFACE = args.INTERFACE
+
+    # Definitely set interface at this point
+    scanner.set_interface(INTERFACE)
+
+   # Floorplan image
+    if args.IMAGE is None:
+        IMAGE = ask_for_floorplan(app)
+    else:
+        IMAGE = args.IMAGE
+
+    # Title
+    if args.TITLE is None:
+        TITLE = ask_for_title(app)
+    else:
+        TITLE = args.TITLE
+
     frm = MainFrame(
-        args.IMAGE, args.INTERFACE, args.IPERF3_SERVER, args.TITLE, args.scan,
-        args.BSSID, args.ding, args.ding_command, args.IPERF3_DURATION, None,
-        title='wifi-survey: %s' % args.TITLE,
+        IMAGE, args.IPERF3_SERVER, TITLE, args.scan,
+        args.BSSID, args.ding, args.ding_command, args.IPERF3_DURATION,
+        scanner, None, title='wifi-survey: %s' % args.TITLE,
     )
     frm.Show()
     frm.SetStatusText('%s' % frm.pnl.GetSize())

From 4748d0dc27c26dcd85ea3709584d9f30d5ce150a Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:42:24 +0100
Subject: [PATCH 08/12] Store used image filename in JSON file so wifi-heatmaps
 works with TITLE alone. This can still be overwritten when explicitly
 specifying an image.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 README.rst                     |  4 ++--
 wifi_survey_heatmap/heatmap.py | 35 +++++++++++++++++++++++++---------
 wifi_survey_heatmap/ui.py      | 10 ++++++++--
 3 files changed, 36 insertions(+), 13 deletions(-)

diff --git a/README.rst b/README.rst
index 429c7cf..2f2c4bc 100644
--- a/README.rst
+++ b/README.rst
@@ -112,7 +112,7 @@ Inside Docker, however, this becomes quite a bit more difficult. Currently Pulse
 Heatmap Generation
 ++++++++++++++++++
 
-Once you've performed a survey with a given title and the results are saved in ``Title.json``, run ``wifi-heatmap PNG Title`` to generate heatmap files in the current directory. This process does not require (and shouldn't have) root/sudo and operates only on the JSON data file. For this, it will look better if you use a PNG without the measurement location marks.
+Once you've performed a survey with a given title and the results are saved in ``Title.json``, run ``wifi-heatmap TITLE`` to generate heatmap files in the current directory. This process does not require (and shouldn't have) root/sudo and operates only on the JSON data file. For this, it will look better if you use a PNG without the measurement location marks.
 
 You can optionally pass the path to a JSON file mapping the access point MAC addresses (BSSIDs) to friendly names via the ``-a`` / ``--ap-names`` argument. If specified, this will annotate each measurement dot on the heatmap with the name (mapping value) and frequency band of the AP that was connected when the measurement was taken. This can be useful in multi-AP roaming environments.
 
@@ -161,7 +161,7 @@ Note that running with ``--net="host"`` and ``--privileged`` is required in orde
 Heatmap
 +++++++
 
-``docker run -it --rm -v $(pwd):/pwd -w /pwd jantman/python-wifi-survey-heatmap:23429a4 wifi-heatmap floorplan.png DeckTest``
+``docker run -it --rm -v $(pwd):/pwd -w /pwd jantman/python-wifi-survey-heatmap:23429a4 wifi-heatmap Example``
 
 iperf3 server
 +++++++++++++
diff --git a/wifi_survey_heatmap/heatmap.py b/wifi_survey_heatmap/heatmap.py
index 78cee04..fd9bfbe 100644
--- a/wifi_survey_heatmap/heatmap.py
+++ b/wifi_survey_heatmap/heatmap.py
@@ -153,7 +153,6 @@ def __init__(
                 self._ap_names = {
                     x.upper(): y for x, y in json.loads(fh.read()).items()
                 }
-        self._image_path = image_path
         self._layout = None
         self._image_width = 0
         self._image_height = 0
@@ -165,12 +164,24 @@ def __init__(
             self._title += '.json'
         self._ignore_ssids = ignore_ssids
         logger.debug(
-            'Initialized HeatMapGenerator; image_path=%s title=%s',
-            self._image_path, self._title
+            'Initialized HeatMapGenerator; title=%s',
+            self._title
         )
         with open(self._title, 'r') as fh:
             self._data = json.loads(fh.read())
-        logger.info('Loaded %d measurement points', len(self._data))
+        if 'survey_points' not in self._data:
+            logger.error('No survey points found in {}'.format(self._title))
+            exit()
+        logger.info('Loaded %d survey points',
+                    len(self._data['survey_points']))
+
+        # Try to load image from JSON if not overwritten
+        if image_path is None:
+            if 'img_path' not in self._data:
+                logger.error('No image path found in {}'.format(self._title))
+                exit(1)
+            self._image_path = self._data['img_path']
+
         self.thresholds = {}
         if thresholds is not None:
             logger.info('Loading thresholds from: %s', thresholds)
@@ -180,7 +191,7 @@ def __init__(
 
     def load_data(self):
         a = defaultdict(list)
-        for row in self._data:
+        for row in self._data['survey_points']:
             a['x'].append(row['x'])
             a['y'].append(row['y'])
             a['channel'].append(row['result']['channel'])
@@ -196,8 +207,10 @@ def load_data(self):
                 a['udp_download_Mbps'].append(row['result']['udp']['Mbps'])
                 a['jitter_download'].append(row['result']['udp']['jitter_ms'])
             if 'udp-reverse' in row['result']:
-                a['udp_upload_Mbps'].append(row['result']['udp-reverse']['Mbps'])
-                a['jitter_upload'].append(row['result']['udp-reverse']['jitter_ms'])
+                a['udp_upload_Mbps'].append(
+                    row['result']['udp-reverse']['Mbps'])
+                a['jitter_upload'].append(
+                    row['result']['udp-reverse']['jitter_ms'])
             a['tx_power'].append(row['result']['tx_power'])
             a['frequency'].append(row['result']['frequency']*1e-3)
             if 'bitrate' in row['result']:
@@ -258,7 +271,7 @@ def _channel_to_signal(self):
         """
         # build a dict of frequency (GHz) to list of quality values
         channels = defaultdict(list)
-        for row in self._data:
+        for row in self._data['survey_points']:
             for scan in row['result']['scan_results']:
                 ssid = row['result']['scan_results'][scan]['ssid']
                 if ssid in self._ignore_ssids:
@@ -348,6 +361,9 @@ def _plot(self, a, key, title, gx, gy, num_x, num_y):
         if key not in a:
             logger.info("Skipping {} due to insufficient data".format(key))
             return
+        if not len(a['x']) == len(a['y']) == len(a[key]):
+            logger.info("Skipping {} because data has holes".format(key))
+            return
         logger.debug('Plotting: %s', key)
         pp.rcParams['figure.figsize'] = (
             self._image_width / 300, self._image_height / 300
@@ -442,7 +458,8 @@ def parse_args(argv):
     p.add_argument('-c', '--cmap-name', type=str, dest='cname', action='store',
                    default="RdYlBu_r",
                    help='If specified, a valid matplotlib colormap name.')
-    p.add_argument('IMAGE', type=str, help='Path to background image')
+    p.add_argument('-p', '--picture', dest='IMAGE', type=str, action='store',
+                   default=None, help='Path to background image')
     p.add_argument(
         'TITLE', type=str, help='Title for survey (and data filename)'
     )
diff --git a/wifi_survey_heatmap/ui.py b/wifi_survey_heatmap/ui.py
index e260ef3..9615d0e 100644
--- a/wifi_survey_heatmap/ui.py
+++ b/wifi_survey_heatmap/ui.py
@@ -201,7 +201,10 @@ def _load_file(self, fpath):
         with open(fpath, 'r') as fh:
             raw = fh.read()
         data = json.loads(raw)
-        for point in data:
+        if 'survey_points' not in data:
+            logger.error('Trying to load incompatible JSON file')
+            exit(1)
+        for point in data['survey_points']:
             p = SurveyPoint(self, point['x'], point['y'])
             p.set_result(point['result'])
             p.set_is_finished()
@@ -424,8 +427,11 @@ def _ding(self):
         subprocess.call([self.parent.ding_command, self.parent.ding_path])
 
     def _write_json(self):
+        # Only store finished survey points
+        survey_points = [p.as_dict for p in self.survey_points if p.is_finished]
+
         res = json.dumps(
-            [x.as_dict for x in self.survey_points],
+            {'img_path': self.img_path, 'survey_points': survey_points},
             cls=SafeEncoder, indent=2
         )
         with open(self.data_filename, 'w') as fh:

From 7f570e40d03123659c14ce479defcf18eb796739 Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:48:09 +0100
Subject: [PATCH 09/12] Add optional argument --contours N to draw N contours
 in the image (with inline labels)

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 wifi_survey_heatmap/heatmap.py | 56 +++++++++++++++++++++++++---------
 1 file changed, 41 insertions(+), 15 deletions(-)

diff --git a/wifi_survey_heatmap/heatmap.py b/wifi_survey_heatmap/heatmap.py
index fd9bfbe..798e695 100644
--- a/wifi_survey_heatmap/heatmap.py
+++ b/wifi_survey_heatmap/heatmap.py
@@ -51,6 +51,7 @@
 from matplotlib.offsetbox import AnchoredText
 from matplotlib.patheffects import withStroke
 from matplotlib.font_manager import FontManager
+from matplotlib.colors import ListedColormap
 import matplotlib
 
 
@@ -144,7 +145,7 @@ class HeatMapGenerator(object):
     }
 
     def __init__(
-        self, image_path, title, showpoints, cname, ignore_ssids=[], aps=None,
+        self, image_path, title, showpoints, cname, contours, ignore_ssids=[], aps=None,
         thresholds=None
     ):
         self._ap_names = {}
@@ -159,7 +160,8 @@ def __init__(
         self._corners = [(0, 0), (0, 0), (0, 0), (0, 0)]
         self._title = title
         self._showpoints = showpoints
-        self._cname = cname
+        self._cmap = self.get_cmap(cname)
+        self._contours = contours
         if not self._title.endswith('.json'):
             self._title += '.json'
         self._ignore_ssids = ignore_ssids
@@ -189,6 +191,23 @@ def __init__(
                 self.thresholds = json.loads(fh.read())
             logger.debug('Thresholds: %s', self.thresholds)
 
+    def get_cmap(self, cname):
+        multi_string = cname.split('//')
+        if len(multi_string) == 2:
+            cname = multi_string[0]
+            steps = int(multi_string[1])
+            N = 256
+            colormap = cm.get_cmap(cname, N)
+            newcolors = colormap(np.linspace(0, 1, N))
+            rgba = np.array([0, 0, 0, 1])
+            interval = int(N/steps) if steps > 0 else 0
+            for i in range(0,N,interval):
+                newcolors[i] = rgba
+            print(newcolors)
+            return ListedColormap(newcolors)
+        else:
+            return pp.get_cmap(cname)
+
     def load_data(self):
         a = defaultdict(list)
         for row in self._data['survey_points']:
@@ -368,7 +387,8 @@ def _plot(self, a, key, title, gx, gy, num_x, num_y):
         pp.rcParams['figure.figsize'] = (
             self._image_width / 300, self._image_height / 300
         )
-        pp.title(title)
+        fig, ax = pp.subplots()
+        ax.set_title(title)
         if 'min' in self.thresholds.get(key, {}):
             vmin = self.thresholds[key]['min']
             logger.debug('Using min threshold from thresholds: %s', vmin)
@@ -394,36 +414,39 @@ def _plot(self, a, key, title, gx, gy, num_x, num_y):
             # (avoids interpolation artifacts)
             z = numpy.ones((num_y, num_x))*vmin
         # Render the interpolated data to the plot
-        pp.axis('off')
+        ax.axis('off')
         # begin color mapping
-
-        cmap = pp.get_cmap(self._cname)
         norm = matplotlib.colors.Normalize(vmin=vmin, vmax=vmax, clip=True)
-        mapper = cm.ScalarMappable(norm=norm, cmap=cmap)
+        mapper = cm.ScalarMappable(norm=norm, cmap=self._cmap)
         # end color mapping
-        image = pp.imshow(
+        image = ax.imshow(
             z,
             extent=(0, self._image_width, self._image_height, 0),
             alpha=0.5, zorder=100,
-            cmap=cmap, vmin=vmin, vmax=vmax
+            cmap=self._cmap, vmin=vmin, vmax=vmax
         )
-        cbar = pp.colorbar(image)
+        if self._contours is not None:
+            CS = ax.contour(z, colors='k', linewidths=1, levels=self._contours,
+                            extent=(0, self._image_width, self._image_height, 0),
+                            alpha=0.3, zorder=150, origin='upper')
+            ax.clabel(CS, inline=1, fontsize=6)
+        cbar = fig.colorbar(image)
         # Print only one ytick label when there is only one value to be shown
         if vmin == vmax:
             cbar.set_ticks([vmin])
-        pp.imshow(self._layout, interpolation='bicubic', zorder=1, alpha=1)
+        ax.imshow(self._layout, interpolation='bicubic', zorder=1, alpha=1)
         labelsize = FontManager.get_default_size() * 0.4
         if(self._showpoints):
             # begin plotting points
             for idx in range(0, len(a['x'])):
                 if (a['x'][idx], a['y'][idx]) in self._corners:
                     continue
-                pp.plot(
+                ax.plot(
                     a['x'][idx], a['y'][idx],
                     marker='o', markeredgecolor='black', markeredgewidth=1,
                     markerfacecolor=mapper.to_rgba(a[key][idx]), markersize=6
                 )
-                pp.text(
+                ax.text(
                     a['x'][idx], a['y'][idx] - 30,
                     a['ap'][idx], fontsize=labelsize,
                     horizontalalignment='center'
@@ -455,9 +478,12 @@ def parse_args(argv):
                         'a string to label each measurement with, showing '
                         'which AP it was connected to. Useful when doing '
                         'multi-AP surveys.')
-    p.add_argument('-c', '--cmap-name', type=str, dest='cname', action='store',
+    p.add_argument('-c', '--cmap', type=str, dest='CNAME', action='store',
                    default="RdYlBu_r",
                    help='If specified, a valid matplotlib colormap name.')
+    p.add_argument('-n', '--contours', type=int, dest='N', action='store',
+                   default=None,
+                   help='If specified, N contour lines will be added to the graphs')
     p.add_argument('-p', '--picture', dest='IMAGE', type=str, action='store',
                    default=None, help='Path to background image')
     p.add_argument(
@@ -510,7 +536,7 @@ def main():
     showpoints = True if args.showpoints > 0 else False
 
     HeatMapGenerator(
-        args.IMAGE, args.TITLE, showpoints, args.cname,
+        args.IMAGE, args.TITLE, showpoints, args.CNAME, args.N,
         ignore_ssids=args.ignore, aps=args.aps, thresholds=args.thresholds
     ).generate()
 

From e549a8e9f8779e01234428091e055caa2dfe8743 Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Thu, 10 Dec 2020 23:52:39 +0100
Subject: [PATCH 10/12] Ensure survey points are drawn on top of everything
 else when they are used and that contour lines are omitted for uniform data.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 wifi_survey_heatmap/heatmap.py | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/wifi_survey_heatmap/heatmap.py b/wifi_survey_heatmap/heatmap.py
index 798e695..3cdf7ad 100644
--- a/wifi_survey_heatmap/heatmap.py
+++ b/wifi_survey_heatmap/heatmap.py
@@ -239,10 +239,7 @@ def load_data(self):
                 row['result']['ssid'].upper(),
                 row['result']['ssid']
             )
-            if row['result']['frequency'] < 5000:
-                a['ap'].append(ap + '_2.4GHz')
-            else:
-                a['ap'].append(ap + '_5GHz')
+            a['ap'].append(ap + ' ({0:.1f} GHz)'.format(1e-3*int(row['result']['frequency'])))
         return a
 
     def _load_image(self):
@@ -425,15 +422,20 @@ def _plot(self, a, key, title, gx, gy, num_x, num_y):
             alpha=0.5, zorder=100,
             cmap=self._cmap, vmin=vmin, vmax=vmax
         )
-        if self._contours is not None:
+
+        # Draw contours if requested and meaningful in this plot
+        if self._contours is not None and vmin != vmax:
             CS = ax.contour(z, colors='k', linewidths=1, levels=self._contours,
                             extent=(0, self._image_width, self._image_height, 0),
                             alpha=0.3, zorder=150, origin='upper')
             ax.clabel(CS, inline=1, fontsize=6)
         cbar = fig.colorbar(image)
+
         # Print only one ytick label when there is only one value to be shown
         if vmin == vmax:
             cbar.set_ticks([vmin])
+
+        # Draw floorplan itself to the lowest layer with full opacity
         ax.imshow(self._layout, interpolation='bicubic', zorder=1, alpha=1)
         labelsize = FontManager.get_default_size() * 0.4
         if(self._showpoints):
@@ -442,7 +444,7 @@ def _plot(self, a, key, title, gx, gy, num_x, num_y):
                 if (a['x'][idx], a['y'][idx]) in self._corners:
                     continue
                 ax.plot(
-                    a['x'][idx], a['y'][idx],
+                    a['x'][idx], a['y'][idx], zorder=200,
                     marker='o', markeredgecolor='black', markeredgewidth=1,
                     markerfacecolor=mapper.to_rgba(a[key][idx]), markersize=6
                 )

From 2a43eb4d3a9a81500890324a44e576b32373963e Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Sun, 20 Dec 2020 13:03:49 +0100
Subject: [PATCH 11/12] Only try to plot for what we have data in the JSON file

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 wifi_survey_heatmap/heatmap.py | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/wifi_survey_heatmap/heatmap.py b/wifi_survey_heatmap/heatmap.py
index 3cdf7ad..7b2bd38 100644
--- a/wifi_survey_heatmap/heatmap.py
+++ b/wifi_survey_heatmap/heatmap.py
@@ -275,9 +275,13 @@ def generate(self):
         gx, gy = np.meshgrid(x, y)
         gx, gy = gx.flatten(), gy.flatten()
         for k, ptitle in self.graphs.items():
-            self._plot(
-                a, k, '%s - %s' % (self._title, ptitle), gx, gy, num_x, num_y
-            )
+            try:
+                self._plot(
+                    a, k, '%s - %s' % (self._title, ptitle), gx, gy, num_x, num_y
+                )
+            except:
+                logger.warning('Cannot create {} plot: '
+                               'insufficient data'.format(k))
 
     def _channel_to_signal(self):
         """

From 39f4d984225019f69464a282d1e148718a75516d Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Sun, 20 Dec 2020 15:58:18 +0100
Subject: [PATCH 12/12] Allow iperf3 server to be specified as ip:port

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 wifi_survey_heatmap/collector.py | 15 +++++++++++----
 wifi_survey_heatmap/ui.py        |  3 ++-
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/wifi_survey_heatmap/collector.py b/wifi_survey_heatmap/collector.py
index 6730fe0..1c3f772 100644
--- a/wifi_survey_heatmap/collector.py
+++ b/wifi_survey_heatmap/collector.py
@@ -62,11 +62,18 @@ def __init__(self, server_addr, duration, scanner, scan=True):
     def run_iperf(self, udp=False, reverse=False):
         client = iperf3.Client()
         client.duration = self._duration
-        client.server_hostname = self._iperf_server
-        client.port = 5201
+
+        server_parts = self._iperf_server.split(":")
+        if len(server_parts) == 2:
+            client.server_hostname = server_parts[0]
+            client.port = int(server_parts[1])
+        else:
+            client.server_hostname = self._iperf_server
+            client.port = 5201 # substitute some default port
+
         client.protocol = 'udp' if udp else 'tcp'
         client.reverse = reverse
-        logger.debug(
+        logger.info(
             'Running iperf to %s; udp=%s reverse=%s', self._iperf_server,
             udp, reverse
         )
@@ -74,7 +81,7 @@ def run_iperf(self, udp=False, reverse=False):
             res = client.run()
             if res.error is None:
                 break
-            logger.error('iperf error: %s; retrying', res.error)
+            logger.error('iperf error %s; retrying', res.error)
         logger.debug('iperf result: %s', res)
         return res
 
diff --git a/wifi_survey_heatmap/ui.py b/wifi_survey_heatmap/ui.py
index 9615d0e..5023e2b 100644
--- a/wifi_survey_heatmap/ui.py
+++ b/wifi_survey_heatmap/ui.py
@@ -471,7 +471,8 @@ def run_iperf(self, count, udp, reverse):
         # else this is an error
         if tmp.error.startswith('unable to connect to server'):
             self.warn(
-                'ERROR: Unable to connect to iperf server. Aborting.'
+                'ERROR: Unable to connect to iperf server at {}. Aborting.'.
+                format(self.collector._iperf_server)
             )
             return None
         if self.YesNo('iperf error: %s. Retry?' % tmp.error):