Add plumbing and support for crossfading StreamParserBuffers.

media/filters/source_buffer_stream_unittest.cc

Index: media/filters/source_buffer_stream_unittest.cc
diff --git a/media/filters/source_buffer_stream_unittest.cc b/media/filters/source_buffer_stream_unittest.cc
index 9e7373a16ad37d6bf172642fe2388185599b935a..04da573c9c6381cdc1a3f1fc4c877e4c1cc565eb 100644
--- a/media/filters/source_buffer_stream_unittest.cc
+++ b/media/filters/source_buffer_stream_unittest.cc
@@ -6,6 +6,8 @@
 
 #include <string>
 
+#include "base/bind.h"
+#include "base/bind_helpers.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
@@ -27,8 +29,8 @@ class SourceBufferStreamTest : public testing::Test {
  protected:
   SourceBufferStreamTest() {
     config_ = TestVideoConfig::Normal();
-    stream_.reset(new SourceBufferStream(config_, LogCB()));
     SetStreamInfo(kDefaultFramesPerSecond, kDefaultKeyframesPerSecond);
+    stream_.reset(new SourceBufferStream(config_, log_cb()));
   }
 
   void SetMemoryLimit(int buffers_of_data) {
@@ -248,6 +250,11 @@ class SourceBufferStreamTest : public testing::Test {
         << "\nActual: " << actual.AsHumanReadableString();
   }
 
+  const LogCB log_cb() {
+    return base::Bind(&SourceBufferStreamTest::DebugMediaLog,
+                      base::Unretained(this));
+  }
+
   base::TimeDelta frame_duration() const { return frame_duration_; }
 
   scoped_ptr<SourceBufferStream> stream_;
@@ -304,6 +311,21 @@ class SourceBufferStreamTest : public testing::Test {
       EXPECT_EQ(expect_success, stream_->Append(queue));
   }
 
+  // AppendBuffers() allows for the generation of StreamParserBuffers from coded
+  // strings of timestamps separated by spaces.  Supported syntax:
+  //
+  // ##:
+  // Generates a StreamParserBuffer with decode timestamp ##.  E.g., "0 1 2 3".
+  //
+  // ##K:
+  // Indicates the buffer with timestamp ## reflects a keyframe.  E.g., "0K 1".
+  //
+  // S(a# ... y# z#)
+  // Indicates a splice frame buffer should be created with timestamp z#.  The
+  // preceding timestamps a# ... y# will be treated as the fade out preroll for
+  // the splice frame.  If a timestamp within the preroll ends with C the config
+  // id to use for that and subsequent preroll appends is incremented by one.
+  // The config id for non-splice frame appends will not be affected.
   void AppendBuffers(const std::string& buffers_to_append,
                      bool start_new_segment, bool one_by_one,
                      bool expect_success) {
@@ -312,14 +334,39 @@ class SourceBufferStreamTest : public testing::Test {
 
     CHECK_GT(timestamps.size(), 0u);
 
+    bool splice_frame = false;
+    size_t splice_config_id = stream_->append_config_index_;
+    std::vector<scoped_refptr<StreamParserBuffer> > fade_out_preroll;
     SourceBufferStream::BufferQueue buffers;
     for (size_t i = 0; i < timestamps.size(); i++) {
       bool is_keyframe = false;
+      bool last_splice_frame = false;
+      // Handle splice frame starts.
+      if (StartsWithASCII(timestamps[i], "S(", true)) {
+        splice_frame = true;

[acolwell GONE FROM CHROMIUM, 2014/01/15 19:28:50]

nit: Add DCHECK(!splice_frame) to avoid allowing S(S(1 2 3) 5 6)?

[DaleCurtis, 2014/01/15 22:40:56]

Done.

+        // Remove the "S(" off of the token.
+        timestamps[i] = timestamps[i].substr(2, timestamps[i].length());
+      }
+      if (splice_frame && EndsWith(timestamps[i], ")", true)) {
+        splice_frame = false;
+        last_splice_frame = true;
+        // Remove the ")" off of the token.
+        timestamps[i] = timestamps[i].substr(0, timestamps[i].length() - 1);
+      }
+      // Handle config changes within the splice frame.
+      if (splice_frame && EndsWith(timestamps[i], "C", true)) {
+        splice_config_id++;
+        CHECK(splice_config_id < stream_->audio_configs_.size() ||
+              splice_config_id < stream_->video_configs_.size());
+        // Remove the "C" off of the token.
+        timestamps[i] = timestamps[i].substr(0, timestamps[i].length() - 1);
+      }
       if (EndsWith(timestamps[i], "K", true)) {
         is_keyframe = true;
         // Remove the "K" off of the token.
         timestamps[i] = timestamps[i].substr(0, timestamps[i].length() - 1);
       }
+
       int time_in_ms;
       CHECK(base::StringToInt(timestamps[i], &time_in_ms));
 
@@ -330,6 +377,25 @@ class SourceBufferStreamTest : public testing::Test {
           base::TimeDelta::FromMilliseconds(time_in_ms);
       buffer->SetDecodeTimestamp(timestamp);
 
+      if (splice_frame) {
+        if (!fade_out_preroll.empty()) {
+          // Enforce strictly monotonically increasing timestamps.
+          CHECK_GT(
+              timestamp.InMicroseconds(),
+              fade_out_preroll.back()->GetDecodeTimestamp().InMicroseconds());
+        }
+        buffer->SetConfigId(splice_config_id);
+        fade_out_preroll.push_back(buffer);
+        continue;
+      }
+
+      if (last_splice_frame) {
+        // Forbid splice frames without preroll.
+        CHECK(!fade_out_preroll.empty());
+        buffer->SetFadeOutPreroll(fade_out_preroll);
+        fade_out_preroll.clear();
+      }
+
       if (i == 0u && start_new_segment)
         stream_->OnNewMediaSegment(timestamp);
 
@@ -349,6 +415,10 @@ class SourceBufferStreamTest : public testing::Test {
     }
   }
 
+  void DebugMediaLog(const std::string& log) {
+    DVLOG(1) << log;
+  }
+
   int frames_per_second_;
   int keyframes_per_second_;
   base::TimeDelta frame_duration_;
@@ -1346,7 +1416,7 @@ TEST_F(SourceBufferStreamTest, Overlap_OneByOne_TrackBuffer) {
   CheckExpectedRangesByTimestamp("{ [10,160) }");
 
   // Seek to 70ms.
-  SeekToTimestamp(base::TimeDelta::FromMilliseconds(10));
+  SeekToTimestamp(base::TimeDelta::FromMilliseconds(70));

[acolwell GONE FROM CHROMIUM, 2014/01/15 19:28:50]

I'm assuming this is just to make the comment and code match. No behavior change
occurred right?

[DaleCurtis, 2014/01/15 22:40:56]

Correct, test passes as before.

   CheckExpectedBuffers("10K 40");
 
   // Overlap with a new segment from 0 to 120ms.
@@ -1504,7 +1574,7 @@ TEST_F(SourceBufferStreamTest, Overlap_OneByOne_TrackBuffer6) {
   CheckExpectedRangesByTimestamp("{ [10,160) [200,260) }");
 
   // Seek to 70ms.
-  SeekToTimestamp(base::TimeDelta::FromMilliseconds(10));
+  SeekToTimestamp(base::TimeDelta::FromMilliseconds(70));

[acolwell GONE FROM CHROMIUM, 2014/01/15 19:28:50]

ditto?

[DaleCurtis, 2014/01/15 22:40:56]

Ditto.

   CheckExpectedBuffers("10K 40");
 
   // Overlap with a new segment from 0 to 120ms.
@@ -3000,7 +3070,7 @@ TEST_F(SourceBufferStreamTest, SameTimestamp_Video_Overlap_3) {
 TEST_F(SourceBufferStreamTest, SameTimestamp_Audio) {
   AudioDecoderConfig config(kCodecMP3, kSampleFormatF32, CHANNEL_LAYOUT_STEREO,
                             44100, NULL, 0, false);
-  stream_.reset(new SourceBufferStream(config, LogCB()));
+  stream_.reset(new SourceBufferStream(config, log_cb()));
   Seek(0);
   NewSegmentAppend("0K 0K 30K 30 60 60");
   CheckExpectedBuffers("0K 0K 30K 30 60 60");
@@ -3009,7 +3079,7 @@ TEST_F(SourceBufferStreamTest, SameTimestamp_Audio) {
 TEST_F(SourceBufferStreamTest, SameTimestamp_Audio_Invalid_1) {
   AudioDecoderConfig config(kCodecMP3, kSampleFormatF32, CHANNEL_LAYOUT_STEREO,
                             44100, NULL, 0, false);
-  stream_.reset(new SourceBufferStream(config, LogCB()));
+  stream_.reset(new SourceBufferStream(config, log_cb()));
   Seek(0);
   NewSegmentAppend_ExpectFailure("0K 30 30K 60");
 }
@@ -3250,7 +3320,6 @@ TEST_F(SourceBufferStreamTest, Remove_GOPBeingAppended) {
   CheckExpectedBuffers("240K 270 300");
 }
 
-
 TEST_F(SourceBufferStreamTest,
        Remove_PreviousAppendDestroyedAndOverwriteExistingRange) {
   SeekToTimestamp(base::TimeDelta::FromMilliseconds(90));
@@ -3275,6 +3344,120 @@ TEST_F(SourceBufferStreamTest,
   CheckExpectedBuffers("90K 121 151");
 }
 
+TEST_F(SourceBufferStreamTest, SpliceFrame_Basic) {
+  Seek(0);
+  NewSegmentAppend("0K S(3K 6 9 10) 15 20 S(25K 30 35) 40");
+  CheckExpectedBuffers("0K 3K 6 9");

[acolwell GONE FROM CHROMIUM, 2014/01/15 19:28:50]

Consider adding support for "C" to CheckExpectedBuffers() so that this test
could become something like.

NewSegmentAppend("0K S(3K 6 9 10) 15 20 S(25K 30 35) 40");
CheckExpectedBuffers("0K 3K 6 9 C 10 15 20 25K 30 C 35 40");
CheckNoNextBuffer();

I think it should be pretty straight forward to do so.

[DaleCurtis, 2014/01/15 22:40:56]

Great idea. It loses the ability to verify the config, but there are other tests
for that. Done.

+
+  scoped_refptr<StreamParserBuffer> buffer;
+  EXPECT_EQ(stream_->GetNextBuffer(&buffer), SourceBufferStream::kConfigChange);
+  stream_->GetCurrentVideoDecoderConfig();
+
+  CheckExpectedBuffers("10 15 20 25K 30");
+
+  EXPECT_EQ(stream_->GetNextBuffer(&buffer), SourceBufferStream::kConfigChange);
+  stream_->GetCurrentVideoDecoderConfig();
+
+  CheckExpectedBuffers("35 40");
+  CheckNoNextBuffer();
+}
+
+TEST_F(SourceBufferStreamTest, SpliceFrame_SeekClearsSplice) {
+  Seek(0);
+  NewSegmentAppend("0K S(3K 6 9 10) 15K 20");
+  CheckExpectedBuffers("0K 3K 6");
+
+  SeekToTimestamp(base::TimeDelta::FromMilliseconds(15));
+  CheckExpectedBuffers("15K 20");
+  CheckNoNextBuffer();
+}
+
+TEST_F(SourceBufferStreamTest, SpliceFrame_SeekClearsSpliceFromTrackBuffer) {
+  Seek(0);
+  NewSegmentAppend("0K 2K S(3K 6 9 10) 15K 20");
+  CheckExpectedBuffers("0K 2K");
+
+  // Overlap the existing segment.
+  NewSegmentAppend("5K 15K 20");
+  CheckExpectedBuffers("3K 6");
+
+  SeekToTimestamp(base::TimeDelta::FromMilliseconds(15));
+  CheckExpectedBuffers("15K 20");
+  CheckNoNextBuffer();
+}
+
+TEST_F(SourceBufferStreamTest, SpliceFrame_ConfigChangeWithinSplice) {
+  VideoDecoderConfig new_config = TestVideoConfig::Large();
+  ASSERT_FALSE(new_config.Matches(config_));
+  CheckConfig(config_);
+
+  // Add a new video config, then reset the config index back to the original.
+  stream_->UpdateVideoConfig(new_config);
+  stream_->UpdateVideoConfig(config_);
+
+  Seek(0);
+  CheckConfig(config_);
+  NewSegmentAppend("0K S(3K 6C 9 10) 15");
+  CheckExpectedBuffers("0K 3K");
+
+  scoped_refptr<StreamParserBuffer> buffer;
+  EXPECT_EQ(stream_->GetNextBuffer(&buffer), SourceBufferStream::kConfigChange);
+  CheckConfig(new_config);
+  CheckExpectedBuffers("6 9");
+
+  EXPECT_EQ(stream_->GetNextBuffer(&buffer), SourceBufferStream::kConfigChange);
+  CheckConfig(config_);
+  CheckExpectedBuffers("10 15");
+  CheckNoNextBuffer();
+}
+
+TEST_F(SourceBufferStreamTest, SpliceFrame_BasicFromTrackBuffer) {
+  Seek(0);
+  NewSegmentAppend("0K 5K S(8K 9 10) 20");
+  CheckExpectedBuffers("0K 5K");
+
+  // Overlap the existing segment.
+  NewSegmentAppend("5K 20");
+  CheckExpectedBuffers("8K 9");
+
+  scoped_refptr<StreamParserBuffer> buffer;
+  EXPECT_EQ(stream_->GetNextBuffer(&buffer), SourceBufferStream::kConfigChange);
+  stream_->GetCurrentVideoDecoderConfig();
+
+  CheckExpectedBuffers("10 20");
+  CheckNoNextBuffer();
+}
+
+TEST_F(SourceBufferStreamTest,
+       SpliceFrame_ConfigChangeWithinSpliceFromTrackBuffer) {
+  VideoDecoderConfig new_config = TestVideoConfig::Large();
+  ASSERT_FALSE(new_config.Matches(config_));
+  CheckConfig(config_);
+
+  // Add a new video config, then reset the config index back to the original.
+  stream_->UpdateVideoConfig(new_config);
+  stream_->UpdateVideoConfig(config_);
+
+  Seek(0);
+  CheckConfig(config_);
+  NewSegmentAppend("0K 5K S(7K 8C 9 10) 20");
+  CheckExpectedBuffers("0K 5K");
+
+  // Overlap the existing segment.
+  NewSegmentAppend("5K 20");
+  CheckExpectedBuffers("7K");
+
+  scoped_refptr<StreamParserBuffer> buffer;
+  EXPECT_EQ(stream_->GetNextBuffer(&buffer), SourceBufferStream::kConfigChange);
+  CheckConfig(new_config);
+  CheckExpectedBuffers("8 9");
+
+  EXPECT_EQ(stream_->GetNextBuffer(&buffer), SourceBufferStream::kConfigChange);
+  CheckConfig(config_);
+  CheckExpectedBuffers("10 20");
+  CheckNoNextBuffer();
+}
+
 // TODO(vrk): Add unit tests where keyframes are unaligned between streams.
 // (crbug.com/133557)