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 6ad64bc33f601de042309c8c869626d2f700a716..604eb1465342845e8c0011afd0fe1b622824751b 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 +826,23 @@ 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
-    // is implemented.
 
-#if !defined(WEBRTC_ANDROID)
+    // LibJpeg is not available on iOS.
+#if !defined(WEBRTC_IOS)
+    // Saving only the worst frame for manual analysis. Intention here is to
+    // only detect video corruptions and not to track picture quality. Thus,
+    // jpeg is used here.
     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());
-      RTC_DCHECK(res);
-      frame_writer.Close();
+      std::string output_dir;
+      if (!test::GetTestOutputDir(&output_dir)) {
+        output_dir = "";

[sprang_webrtc, 2017/08/17 15:27:50]

Should not write to file instead, if flag is not set?

[ilnik, 2017/08/18 08:42:05]

Currently it always outputs the worst frame. This is here just to not ignore
return values. I have added a separate flag for that.

Also, the check here isn't needed because if there is no output dir defined, it
will be left as "" anyway. Removed.

+      }
+      std::string output_path =
+          rtc::Pathname(output_dir, test_label_ + ".jpg").pathname();
+      fprintf(stderr, "Saving worst frame to %s\n", output_path.c_str());

[sprang_webrtc, 2017/08/17 15:27:50]

use LOG macro instead

[ilnik, 2017/08/18 08:42:05]

Done.

+      test::JpegFrameWriter frame_writer(output_path);
+      RTC_CHECK(frame_writer.WriteFrame(worst_frame_->frame,
+                                        100 /*best quality*/));
     }
 #endif