From 60508f8621ae9188871c68a7317413a274071550 Mon Sep 17 00:00:00 2001
From: Henrik Lundin <henrik.lundin@webrtc.org>
Date: Wed, 3 Jun 2015 09:38:23 +0200
Subject: [PATCH] Small changes to rtpAnalyze Matlab script

These changes are in response to post-commit comments in
https://webrtc-codereview.appspot.com/47339004/.

BUG=webrtc:2692
R=tina.legrand@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/50189004

Cr-Commit-Position: refs/heads/master@{#9358}
---
 tools/matlab/rtpAnalyze.m | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/tools/matlab/rtpAnalyze.m b/tools/matlab/rtpAnalyze.m
index 6da25f6a4d..7ad45631b9 100644
--- a/tools/matlab/rtpAnalyze.m
+++ b/tools/matlab/rtpAnalyze.m
@@ -15,13 +15,14 @@ function rtpAnalyze( input_file )
 % in the file PATENTS.  All contributing project authors may
 % be found in the AUTHORS file in the root of the source tree.
 
-
-
 [SeqNo,TimeStamp,ArrTime,Size,PT,M,SSRC] = importfile(input_file);
 
-%% Find streams
+%% Find streams.
 [uSSRC, ~, uix] = unique(SSRC);
 
+% If there are multiple streams, select one and purge the other
+% streams from the data vectors. If there is only one stream, the
+% vectors are good to use as they are.
 if length(uSSRC) > 1
     for i=1:length(uSSRC)
         uPT = unique(PT(uix == i));
@@ -36,7 +37,8 @@ if length(uSSRC) > 1
     if sel < 1 || sel > length(uSSRC)
         error('Out of range');
     end
-    ix = find(uix==sel);
+    ix = find(uix == sel);
+    % This is where the data vectors are trimmed.
     SeqNo = SeqNo(ix);
     TimeStamp = TimeStamp(ix);
     ArrTime = ArrTime(ix);
@@ -46,11 +48,11 @@ if length(uSSRC) > 1
     SSRC = SSRC(ix);
 end
 
-%% Unwrap SeqNo and TimeStamp
+%% Unwrap SeqNo and TimeStamp.
 SeqNoUW = maxUnwrap(SeqNo, 65535);
 TimeStampUW = maxUnwrap(TimeStamp, 4294967295);
 
-%% Generate some stats for the stream
+%% Generate some stats for the stream.
 fprintf('Statistics:\n');
 fprintf('SSRC: %s\n', SSRC{1});
 uPT = unique(PT);
@@ -73,10 +75,10 @@ fprintf('Common packet sizes:\n');
 for i = 1:length(utsdiff)
     fprintf('  %i samples (%i%%)\n', ...
         utsdiff(i), ...
-        round(100 * length(find(ixtsdiff==i))/length(ixtsdiff)));
+        round(100 * length(find(ixtsdiff == i))/length(ixtsdiff)));
 end
 
-%% Trying to figure out sample rate
+%% Trying to figure out sample rate.
 fs_est = (TimeStampUW(end) - TimeStampUW(1)) / (ArrTime(end) - ArrTime(1));
 fs_vec = [8, 16, 32, 48];
 fs = 0;
@@ -108,10 +110,11 @@ fprintf('Clock drift: %.2f%%\n', ...
 
 fprintf('Sent average bitrate: %i kbps\n', ...
     round(sum(Size) * 8 / (SendTimeMs(end)-SendTimeMs(1))));
+
 fprintf('Received average bitrate: %i kbps\n', ...
     round(sum(Size) * 8 / (ArrTime(end)-ArrTime(1))));
 
-%% Plots
+%% Plots.
 delay = ArrTime - SendTimeMs;
 delay = delay - min(delay);
 figure
@@ -127,6 +130,7 @@ xlabel('Send time [s]');
 ylabel('Send bitrate [kbps]');
 end
 
+%% Auto-generated subfunction.
 function [SeqNo,TimeStamp,SendTime,Size,PT,M,SSRC] = ...
     importfile(filename, startRow, endRow)
 %IMPORTFILE Import numeric data from a text file as column vectors.