Add Jpeg frame writer for test support.

webrtc/video/video_quality_test.cc

Index: webrtc/video/video_quality_test.cc
diff --git a/webrtc/video/video_quality_test.cc b/webrtc/video/video_quality_test.cc
index aa5ff7121d9359e378cace1941a080e480a6a2d1..cde4b91ffc303d25e1a89a0e745b408e99fc2559 100644
--- a/webrtc/video/video_quality_test.cc
+++ b/webrtc/video/video_quality_test.cc
@@ -36,6 +36,7 @@
 #include "webrtc/rtc_base/format_macros.h"
 #include "webrtc/rtc_base/memory_usage.h"
 #include "webrtc/rtc_base/optional.h"
+#include "webrtc/rtc_base/pathutils.h"
 #include "webrtc/rtc_base/platform_file.h"
 #include "webrtc/rtc_base/timeutils.h"
 #include "webrtc/system_wrappers/include/cpu_info.h"
@@ -46,6 +47,7 @@
 #include "webrtc/test/statistics.h"
 #include "webrtc/test/testsupport/fileutils.h"
 #include "webrtc/test/testsupport/frame_writer.h"
+#include "webrtc/test/testsupport/test_output.h"
 #include "webrtc/test/vcm_capturer.h"
 #include "webrtc/test/video_renderer.h"
 #include "webrtc/voice_engine/include/voe_base.h"
@@ -824,27 +826,21 @@ class VideoAnalyzer : public PacketReceiver,
       // will be flaky.
     PrintResult("memory_usage", memory_usage_, " bytes");
 #endif
-    // TODO(ilnik): enable frame writing for android, once jpeg frame writer

[pbos-webrtc, 2017/07/25 18:10:28]

Shouldn't this be lossless to actually show what it looks like? E.g. would you
want to write a png here?

[ilnik, 2017/07/25 19:05:54]

Space is probably the most concern here, as these frames will be saved for all
~30 testcases several times a day. Also, main point here is to manually check
for corruptions in the video which will be noticable even with minor jpeg
artifacts.

-    // is implemented.
 
-#if !defined(WEBRTC_ANDROID)
+    // LibJpeg is not available on iOS.
+#if !defined(WEBRTC_IOS)
     if (worst_frame_) {
-      test::Y4mFrameWriterImpl frame_writer(test_label_ + ".y4m",
-                                            worst_frame_->frame.width(),
-                                            worst_frame_->frame.height(), 1);
-      bool res = frame_writer.Init();
-      RTC_DCHECK(res);
-      size_t length =
-          CalcBufferSize(VideoType::kI420, worst_frame_->frame.width(),
-                         worst_frame_->frame.height());
-      rtc::Buffer extracted_buffer(length);
-      size_t extracted_length =
-          ExtractBuffer(worst_frame_->frame.video_frame_buffer()->ToI420(),
-                        length, extracted_buffer.data());
-      RTC_DCHECK_EQ(extracted_length, frame_writer.FrameLength());
-      res = frame_writer.WriteFrame(extracted_buffer.data());
+      std::string output_dir;
+      bool res = test::GetTestOutputDir(&output_dir);
+      if (!res) {
+        output_dir = "";
+      }
+      std::string output_path =
+          rtc::Pathname(output_dir, test_label_ + ".jpg").pathname();
+      fprintf(stderr, "Saving worst frame to %s\n", output_path.c_str());
+      test::JpegFrameWriter frame_writer(output_path);
+      res = frame_writer.WriteFrame(worst_frame_->frame, 90 /*quality*/);

[pbos-webrtc, 2017/07/25 18:10:28]

90 is definitely nowhere near lossless? Are sizes that big of a concern if
you're only saving one? Why wasn't saving a y4m frame OK?

[ilnik, 2017/07/25 19:05:54]

We are saving one for each of ~30 testcases each run on perfbots. There will be
more testcases in the future.  Also, jpeg is much nicer to view than y4m.
 
I am changing that quality setting to 100. This is the best possible. Still not
lossless, but with very minor artifacts.

       RTC_DCHECK(res);
-      frame_writer.Close();
     }
 #endif