support adaptive playback in MSE

media/base/android/media_decoder_job.cc

Index: media/base/android/media_decoder_job.cc
diff --git a/media/base/android/media_decoder_job.cc b/media/base/android/media_decoder_job.cc
index 97fa39b528dd2257bd9048edeede9ff678d0d71f..ef5fba7f58551b581186beafe45ac36687a908de 100644
--- a/media/base/android/media_decoder_job.cc
+++ b/media/base/android/media_decoder_job.cc
@@ -332,16 +332,16 @@ void MediaDecoderJob::DecodeCurrentAccessUnit(
   const AccessUnit& access_unit = CurrentAccessUnit();
   if (CurrentAccessUnit().status == DemuxerStream::kConfigChanged) {
     int index = CurrentReceivedDataChunkIndex();
-    bool config_changed = SetDemuxerConfigs(
-        received_data_[index].demuxer_configs[0]);
-    if (config_changed)
+    const DemuxerConfigs& configs = received_data_[index].demuxer_configs[0];
+    bool reconfigure_needed = IsCodecReconfigureNeeded(configs);
+    if (SetDemuxerConfigs(configs))
       config_changed_cb_.Run();

[wolenetz, 2014/06/06 23:28:07]

Should we wait to tell the renderer that the config has changed until we
complete draining (if any) and create the new decoder? I'm fine with this as a
separate CL.

[qinmin, 2014/06/07 01:31:55]

Yes, that should be the correct behavior. However, the fix needs to touch
multiple places where drain_decoder_ gets cleared. Added TODO here.

On 2014/06/06 23:28:07, wolenetz wrote:

     if (!drain_decoder_) {

[wolenetz, 2014/06/06 23:28:07]

If !reconfigure_needed, we still drain previous decoder and do the old
OnDecoderDrained() logic. Or am I misreading?

[qinmin, 2014/06/07 01:31:55]

If !reconfigure_needed, we will keep the previous decoder and keep on decoding
the data it currently has. So there is no need to drain it.
However, if need_to_reconfig_decoder_job_ is true, we will recreate a new
decoder even if !reconfigure_needed is true. This could happen when surface
changes or a seek is conducted. In both cases, we should abadon the current
buffered data and recreate a new codec.


On 2014/06/06 23:28:07, wolenetz wrote:

[wolenetz, 2014/06/09 18:22:39]

Thank you for clarifying. Yes, I was misreading.

       // If we haven't decoded any data yet, just skip the current access unit
       // and request the MediaCodec to be recreated on next Decode().
-      if (skip_eos_enqueue_ || !config_changed) {
+      if (skip_eos_enqueue_ || !reconfigure_needed) {
         need_to_reconfig_decoder_job_ =
-            need_to_reconfig_decoder_job_ || config_changed;
+            need_to_reconfig_decoder_job_ || reconfigure_needed;
         ui_task_runner_->PostTask(FROM_HERE, base::Bind(
             &MediaDecoderJob::OnDecodeCompleted, base::Unretained(this),
             MEDIA_CODEC_OUTPUT_FORMAT_CHANGED, kNoTimestamp(), kNoTimestamp()));
@@ -632,6 +632,13 @@ bool MediaDecoderJob::CreateMediaCodecBridge() {
   return CreateMediaCodecBridgeInternal();
 }
 
+bool MediaDecoderJob::IsCodecReconfigureNeeded(
+    const DemuxerConfigs& configs) const {
+  if (!AreDemuxerConfigsChanged(configs))
+    return false;
+  return true;
+}
+
 void MediaDecoderJob::ReleaseMediaCodecBridge() {
   if (!media_codec_bridge_)
     return;