Fix rtp_analyzer tool

- Make rtp_analyzer work with a single SSRC
- Simplify rtp_analyzer.sh (it allows to run the python script
  from any directory)
- Update README.md (simplified, added missing dependency)

Bug: webrtc:10829
Change-Id: Idb82e7228918a973778762a39b732ce3b26b6bbc
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/146711
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28668}

rtc_tools/py_event_log_analyzer/README

@@ -1,32 +0,0 @@
-This file describes how to set up and use the RTP log analyzer.
-
-First build the tool with
-
-    ninja -C out/my_build webrtc:rtp_analyzer
-
-The tool is built by default, so
-
-    ninja -C out/my_build
-
-is enough.
-
-After building, run the tool as follows:
-
-    ./out/my_build/rtp_analyzer.sh [options] <rtc event log>
-
-where <rtc event log> is a recorded RTC event log, which is stored in
-protobuf format. Such logs are generated in multiple ways, e.g. by
-Chrome through the chrome://webrtc-internals page.
-
-Options:
-  -h, --help            show this help message and exit
-  --dump_header_to_stdout
-                        print header info to stdout; similar to rtp_analyze
-  --query_sample_rate   always query user for real sample rate
-
-The script has been tested to work in python versions 3.4.1 and 2.7.6,
-but should work in all python versions.
-
-Working versions of NumPy (http://www.numpy.org/) and matplotlib
-(http://matplotlib.org/) are needed to run this tool. See this link
-with installation instructions (http://www.scipy.org/install.html).

rtc_tools/py_event_log_analyzer/README.md

@@ -0,0 +1,26 @@
+# RTP log analyzer
+This file describes how to set up and use the RTP log analyzer.
+
+## Build
+
+```shell
+$ autoninja -C out/my_build webrtc:rtp_analyzer
+```
+
+## Usage
+
+```shell
+./out/my_build/rtp_analyzer.sh [options] /path/to/rtc_event.log
+```
+
+where `/path/to/rtc_event.log` is a recorded RTC event log, which is stored in
+protobuf format. Such logs are generated in multiple ways, e.g. by Chrome
+through the chrome://webrtc-internals page.
+
+Use `--help` for the options.
+
+The script requires Python (2.7 or 3+) and it has the following dependencies:
+Dependencies (available on pip):
+- matplotlib (http://matplotlib.org/)
+- numpy (http://www.numpy.org/)
+- protobuf (https://pypi.org/project/protobuf/)

rtc_tools/py_event_log_analyzer/rtp_analyzer.py

@@ -90,7 +90,7 @@ class RTPStatistics(object):
     """Queries user for SSRC."""
 
     if len(self.ssrc_frequencies) == 1:
-      chosen_ssrc = self.ssrc_frequencies[0][-1]
+      chosen_ssrc = self.ssrc_frequencies.keys()[0]
       self.PrintSsrcInfo("", chosen_ssrc)
       return chosen_ssrc
 

rtc_tools/py_event_log_analyzer/rtp_analyzer.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 #  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
 #
 #  Use of this source code is governed by a BSD-style license
@@ -6,12 +6,5 @@
 #  tree. An additional intellectual property rights grant can be found
 #  in the file PATENTS.  All contributing project authors may
 #  be found in the AUTHORS file in the root of the source tree.
-set -e
-WORKING_DIR=$(pwd)
-cd $(dirname $0)
-PYTHONPATH="../../third_party/protobuf/python/"
-if [ -z ${PYTHON_EXECUTABLE+x} ]
-then
-    PYTHON_EXECUTABLE=python3
-fi
-exec $PYTHON_EXECUTABLE "rtp_analyzer.py" $@ --working_dir $WORKING_DIR
+BASE_DIR=`dirname $0`
+python "${BASE_DIR}/rtp_analyzer.py" $@ --working_dir $BASE_DIR