Make path to wav file for jitter buffer simulation in event_log_visualizer configurable.

webrtc/rtc_tools/event_log_visualizer/main.cc

Index: webrtc/rtc_tools/event_log_visualizer/main.cc
diff --git a/webrtc/rtc_tools/event_log_visualizer/main.cc b/webrtc/rtc_tools/event_log_visualizer/main.cc
index 7df0374484aec628b85e76f2884ab14054c189e7..d9760d1dc4ef19210be5ba2626cf0258c3c2a944 100644
--- a/webrtc/rtc_tools/event_log_visualizer/main.cc
+++ b/webrtc/rtc_tools/event_log_visualizer/main.cc
@@ -88,6 +88,9 @@ DEFINE_string(
     "E.g. running with --force_fieldtrials=WebRTC-FooFeature/Enabled/"
     " will assign the group Enabled to field trial WebRTC-FooFeature. Multiple "
     "trials are separated by \"/\"");
+DEFINE_string(wav_filename,
+              "",

[hlundin-webrtc, 2017/08/15 11:54:45]

Is it possible to use
webrtc::test::ResourcePath("audio_processing/conversational_speech/EN_script2_F_sp2_B1",
"wav") as a default value here?

If not, I have other suggestions below.

[owb1, 2017/08/15 13:01:28]

This does not seem to work and results in an undefined value for the flag.

[hlundin-webrtc, 2017/08/15 13:51:17]

Acknowledged. I thought so too, but figured that maybe some compiler magic could
work it out. Now when I look at the implementation of ResourcePath, I see that
it checks for the existence of files, which would be impossible to do accurately
during compile time.

+              "Path to wav file used for simulation of jitter buffer");
 DEFINE_bool(help, false, "prints this message");
 
 DEFINE_bool(
@@ -241,11 +244,15 @@ int main(int argc, char* argv[]) {
   }
 
   if (FLAG_plot_all || FLAG_plot_audio_jitter_buffer) {
-    analyzer.CreateAudioJitterBufferGraph(
-        webrtc::test::ResourcePath(
-            "audio_processing/conversational_speech/EN_script2_F_sp2_B1",
-            "wav"),
-        48000, collection->AppendNewPlot());
+    std::string wav_path;

[hlundin-webrtc, 2017/08/15 11:54:45]

If you can't set the flag default as above, I suggest you change to the
following:

const std::string wav_path = FLAG_wav_filename.empty() ?
webrtc::test::ResourcePath("audio_processing/conversational_speech/EN_script2_F_sp2_B1",
"wav") : 
FLAG_wav_filename;

[owb1, 2017/08/15 13:01:28]

I implemented this version. FLAG_wav_filename is a character array, therefore I
used strlen instead of .empty().

[hlundin-webrtc, 2017/08/15 13:51:17]

Oh, I thought it was a c++ string. I must be confusing it with gflags. Then your
initial approach with an if-statement is not so bad. You can decide if you want
to go back to that, or keep the current version with the conditional.

+    if (FLAG_wav_filename[0] != '\0') {
+      wav_path = FLAG_wav_filename;
+    } else {
+      wav_path = webrtc::test::ResourcePath(
+          "audio_processing/conversational_speech/EN_script2_F_sp2_B1", "wav");
+    }
+    analyzer.CreateAudioJitterBufferGraph(wav_path, 48000,
+                                          collection->AppendNewPlot());
   }
 
   collection->Draw();