Refactor MSE implementation on Android to simplify the logic and improve the performance

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 24a82367c1d07857f343ac4ea96735010849543e..66214072063083d02881ec2a6b763a0b83cadace 100644
--- a/media/base/android/media_decoder_job.cc
+++ b/media/base/android/media_decoder_job.cc
@@ -9,6 +9,7 @@
 #include "base/debug/trace_event.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "media/base/android/media_codec_bridge.h"
+#include "media/base/android/media_drm_bridge.h"
 #include "media/base/bind_to_current_loop.h"
 #include "media/base/buffers.h"
 
@@ -21,28 +22,33 @@ static const int kMediaCodecTimeoutInMilliseconds = 250;
 
 MediaDecoderJob::MediaDecoderJob(
     const scoped_refptr<base::SingleThreadTaskRunner>& decoder_task_runner,
-    MediaCodecBridge* media_codec_bridge,
-    const base::Closure& request_data_cb)
+    const base::Closure& request_data_cb,
+    const base::Closure& on_demuxer_config_changed_cb)
     : ui_task_runner_(base::MessageLoopProxy::current()),
       decoder_task_runner_(decoder_task_runner),
-      media_codec_bridge_(media_codec_bridge),
       needs_flush_(false),
       input_eos_encountered_(false),
       output_eos_encountered_(false),
       skip_eos_enqueue_(true),
       prerolling_(true),
       request_data_cb_(request_data_cb),
+      on_demuxer_config_changed_cb_(on_demuxer_config_changed_cb),
       current_demuxer_data_index_(0),
       input_buf_index_(-1),
+      is_content_encrypted_(false),
       stop_decode_pending_(false),
       destroy_pending_(false),
       is_requesting_demuxer_data_(false),
       is_incoming_data_invalid_(false),
-      weak_factory_(this) {
+      release_resources_pending_(false),
+      drm_bridge_(NULL),
+      drain_decoder_(false) {
   InitializeReceivedData();
 }
 
-MediaDecoderJob::~MediaDecoderJob() {}
+MediaDecoderJob::~MediaDecoderJob() {
+  ReleaseMediaCodecBridge();
+}
 
 void MediaDecoderJob::OnDataReceived(const DemuxerData& data) {
   DVLOG(1) << __FUNCTION__ << ": " << data.access_units.size() << " units";
@@ -74,7 +80,7 @@ void MediaDecoderJob::OnDataReceived(const DemuxerData& data) {
   base::Closure done_cb = base::ResetAndReturn(&on_data_received_cb_);
 
   // If this data request is for the inactive chunk, or |on_data_received_cb_|
-  // was set to null by ClearData() or Release(), do nothing.
+  // was set to null by Flush() or Release(), do nothing.
   if (done_cb.is_null())
     return;
 
@@ -102,7 +108,7 @@ void MediaDecoderJob::Prefetch(const base::Closure& prefetch_cb) {
   RequestData(prefetch_cb);
 }
 
-scoped_ptr<DemuxerConfigs> MediaDecoderJob::Decode(
+bool MediaDecoderJob::Decode(
     base::TimeTicks start_time_ticks,
     base::TimeDelta start_presentation_timestamp,
     const DecoderCallback& callback) {
@@ -110,6 +116,20 @@ scoped_ptr<DemuxerConfigs> MediaDecoderJob::Decode(
   DCHECK(on_data_received_cb_.is_null());
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
 
+  if (!media_codec_bridge_ || need_to_reconfig_decoder_job_) {
+    need_to_reconfig_decoder_job_ = !CreateMediaCodecBridge();
+    if (drain_decoder_) {
+      // Decoder has been recreated, stop draining.
+      drain_decoder_ = false;
+      input_eos_encountered_ = false;
+      output_eos_encountered_ = false;
+      access_unit_index_[current_demuxer_data_index_]++;
+    }
+    skip_eos_enqueue_ = true;
+    if (need_to_reconfig_decoder_job_)
+      return false;
+  }
+
   decode_cb_ = callback;
 
   if (!HasData()) {
@@ -117,19 +137,11 @@ scoped_ptr<DemuxerConfigs> MediaDecoderJob::Decode(
                            base::Unretained(this),
                            start_time_ticks,
                            start_presentation_timestamp));
-    return scoped_ptr<DemuxerConfigs>();
-  }
-
-  if (DemuxerStream::kConfigChanged == CurrentAccessUnit().status) {
-    decode_cb_.Reset();
-    size_t index = CurrentReceivedDataChunkIndex();
-    CHECK_EQ(1u, received_data_[index].demuxer_configs.size());
-    return scoped_ptr<DemuxerConfigs>(new DemuxerConfigs(
-        received_data_[index].demuxer_configs[0]));
+    return true;
   }
 
   DecodeCurrentAccessUnit(start_time_ticks, start_presentation_timestamp);
-  return scoped_ptr<DemuxerConfigs>();
+  return true;
 }
 
 void MediaDecoderJob::StopDecode() {
@@ -138,12 +150,27 @@ void MediaDecoderJob::StopDecode() {
   stop_decode_pending_ = true;
 }
 
+bool MediaDecoderJob::OutputEOSReached() const {
+  return !drain_decoder_ && output_eos_encountered_;
+}
+
 void MediaDecoderJob::Flush() {
+  DVLOG(1) << __FUNCTION__;
+  DCHECK(ui_task_runner_->BelongsToCurrentThread());
+  DCHECK(on_data_received_cb_.is_null());
   DCHECK(decode_cb_.is_null());
 
+  // Clean up the received data.
+  current_demuxer_data_index_ = 0;
+  InitializeReceivedData();
+  if (is_requesting_demuxer_data_)
+    is_incoming_data_invalid_ = true;
+  input_eos_encountered_ = false;
+  output_eos_encountered_ = false;
+  drain_decoder_ = false;
+
   // Do nothing, flush when the next Decode() happens.
   needs_flush_ = true;
-  ClearData();
 }
 
 void MediaDecoderJob::BeginPrerolling(base::TimeDelta preroll_timestamp) {
@@ -155,13 +182,41 @@ void MediaDecoderJob::BeginPrerolling(base::TimeDelta preroll_timestamp) {
   prerolling_ = true;
 }
 
+void MediaDecoderJob::ReleaseDecoderResources() {
+  DVLOG(1) << __FUNCTION__;
+  DCHECK(ui_task_runner_->BelongsToCurrentThread());
+  if (decode_cb_.is_null()) {
+    DCHECK(!drain_decoder_);
+    // Since the decoder job is not decoding data, we can safely destroy
+    // |media_codec_bridge_|.
+    ReleaseMediaCodecBridge();
+    return;
+  }
+
+  // Release |media_codec_bridge_| once decoding is completed.
+  release_resources_pending_ = true;
+}
+
+bool MediaDecoderJob::SetDemuxerConfigs(const DemuxerConfigs& configs) {
+  bool config_changed = IsDemuxerConfigChanged(configs);
+  if (config_changed)
+    UpdateDemuxerConfigs(configs);
+  return config_changed;
+}
+
+base::android::ScopedJavaLocalRef<jobject> MediaDecoderJob::GetMediaCrypto() {
+  base::android::ScopedJavaLocalRef<jobject> media_crypto;
+  if (drm_bridge_)
+    media_crypto = drm_bridge_->GetMediaCrypto();
+  return media_crypto;
+}
+
 void MediaDecoderJob::Release() {
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
   DVLOG(1) << __FUNCTION__;
 
-  // If the decoder job is not waiting for data, and is still decoding, we
-  // cannot delete the job immediately.
-  destroy_pending_ = on_data_received_cb_.is_null() && is_decoding();
+  // If the decoder job is still decoding, we cannot delete the job immediately.
+  destroy_pending_ = is_decoding();
 
   request_data_cb_.Reset();
   on_data_received_cb_.Reset();
@@ -175,7 +230,8 @@ void MediaDecoderJob::Release() {
   delete this;
 }
 
-MediaCodecStatus MediaDecoderJob::QueueInputBuffer(const AccessUnit& unit) {
+MediaCodecStatus MediaDecoderJob::QueueInputBuffer(
+    const AccessUnit& unit, bool drain_decoder) {
   DVLOG(1) << __FUNCTION__;
   DCHECK(decoder_task_runner_->BelongsToCurrentThread());
   TRACE_EVENT0("media", __FUNCTION__);
@@ -202,7 +258,7 @@ MediaCodecStatus MediaDecoderJob::QueueInputBuffer(const AccessUnit& unit) {
     return MEDIA_CODEC_INPUT_END_OF_STREAM;
   }
 
-  if (unit.key_id.empty() || unit.iv.empty()) {
+  if (drain_decoder || unit.key_id.empty() || unit.iv.empty()) {
     DCHECK(unit.iv.empty() || !unit.key_id.empty());
     return media_codec_bridge_->QueueInputBuffer(
         input_buf_index, &unit.data[0], unit.data.size(), unit.timestamp);
@@ -269,21 +325,34 @@ void MediaDecoderJob::DecodeCurrentAccessUnit(
 
   RequestCurrentChunkIfEmpty();
   const AccessUnit& access_unit = CurrentAccessUnit();
-  // If the first access unit is a config change, request the player to dequeue
-  // the input buffer again so that it can request config data.
-  if (access_unit.status == DemuxerStream::kConfigChanged) {
-    ui_task_runner_->PostTask(FROM_HERE,
-                              base::Bind(&MediaDecoderJob::OnDecodeCompleted,
-                                         base::Unretained(this),
-                                         MEDIA_CODEC_DEQUEUE_INPUT_AGAIN_LATER,
-                                         kNoTimestamp(), kNoTimestamp()));
-    return;
+  if (CurrentAccessUnit().status == DemuxerStream::kConfigChanged) {
+    int index = CurrentReceivedDataChunkIndex();
+    bool config_changed = SetDemuxerConfigs(
+        received_data_[index].demuxer_configs[0]);
+    if (config_changed)
+      on_demuxer_config_changed_cb_.Run();
+    if (!drain_decoder_) {
+      // 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) {
+        need_to_reconfig_decoder_job_ =
+            need_to_reconfig_decoder_job_ || config_changed;
+        ui_task_runner_->PostTask(FROM_HERE, base::Bind(
+            &MediaDecoderJob::OnDecodeCompleted, base::Unretained(this),
+            MEDIA_CODEC_OUTPUT_FORMAT_CHANGED, kNoTimestamp(), kNoTimestamp()));
+        return;
+      }
+      // Start draining the decoder so that all the remaining frames are
+      // rendered.
+      drain_decoder_ = true;
+    }
   }
 
   decoder_task_runner_->PostTask(FROM_HERE, base::Bind(
       &MediaDecoderJob::DecodeInternal, base::Unretained(this),
       access_unit,
       start_time_ticks, start_presentation_timestamp, needs_flush_,
+      drain_decoder_,
       media::BindToCurrentLoop(base::Bind(
           &MediaDecoderJob::OnDecodeCompleted, base::Unretained(this)))));
   needs_flush_ = false;
@@ -294,6 +363,7 @@ void MediaDecoderJob::DecodeInternal(
     base::TimeTicks start_time_ticks,
     base::TimeDelta start_presentation_timestamp,
     bool needs_flush,
+    bool drain_decoder,
     const MediaDecoderJob::DecoderCallback& callback) {
   DVLOG(1) << __FUNCTION__;
   DCHECK(decoder_task_runner_->BelongsToCurrentThread());
@@ -336,7 +406,7 @@ void MediaDecoderJob::DecodeInternal(
 
   MediaCodecStatus input_status = MEDIA_CODEC_INPUT_END_OF_STREAM;
   if (!input_eos_encountered_) {
-    input_status = QueueInputBuffer(unit);
+    input_status = QueueInputBuffer(unit, drain_decoder);
     if (input_status == MEDIA_CODEC_INPUT_END_OF_STREAM) {
       input_eos_encountered_ = true;
     } else if (input_status != MEDIA_CODEC_OK) {
@@ -375,7 +445,7 @@ void MediaDecoderJob::DecodeInternal(
   if (output_eos_encountered_)
     status = MEDIA_CODEC_OUTPUT_END_OF_STREAM;
   else if (input_status == MEDIA_CODEC_INPUT_END_OF_STREAM)
-    status = MEDIA_CODEC_INPUT_END_OF_STREAM;
+    status = drain_decoder ? MEDIA_CODEC_OK : MEDIA_CODEC_INPUT_END_OF_STREAM;
 
   bool render_output  = presentation_timestamp >= preroll_timestamp_ &&
       (status != MEDIA_CODEC_OUTPUT_END_OF_STREAM || size != 0u);
@@ -390,7 +460,7 @@ void MediaDecoderJob::DecodeInternal(
     decoder_task_runner_->PostDelayedTask(
         FROM_HERE,
         base::Bind(&MediaDecoderJob::ReleaseOutputBuffer,
-                   weak_factory_.GetWeakPtr(),
+                   base::Unretained(this),
                    buffer_index,
                    size,
                    render_output,
@@ -430,6 +500,9 @@ void MediaDecoderJob::OnDecodeCompleted(
     return;
   }
 
+  if (status == MEDIA_CODEC_OUTPUT_END_OF_STREAM)
+    output_eos_encountered_ = true;
+
   DCHECK(!decode_cb_.is_null());
 
   // If output was queued for rendering, then we have completed prerolling.
@@ -442,8 +515,11 @@ void MediaDecoderJob::OnDecodeCompleted(
     case MEDIA_CODEC_OUTPUT_BUFFERS_CHANGED:
     case MEDIA_CODEC_OUTPUT_FORMAT_CHANGED:
     case MEDIA_CODEC_OUTPUT_END_OF_STREAM:
-      if (!input_eos_encountered_)
+      if (!input_eos_encountered_) {
+        CurrentDataConsumed(
+            CurrentAccessUnit().status == DemuxerStream::kConfigChanged);
         access_unit_index_[current_demuxer_data_index_]++;
+      }
       break;
 
     case MEDIA_CODEC_DEQUEUE_INPUT_AGAIN_LATER:
@@ -455,6 +531,18 @@ void MediaDecoderJob::OnDecodeCompleted(
       break;
   };
 
+  if (status == MEDIA_CODEC_OUTPUT_END_OF_STREAM && drain_decoder_) {
+    OnDecoderDrained();
+    status = MEDIA_CODEC_OK;
+  }
+
+  if (release_resources_pending_) {

[wolenetz, 2014/05/21 00:48:04]

In this case (release_resources_pending_ was true), do we still want to retain
|status| as-is, or change it to OK?

[qinmin, 2014/05/22 00:35:55]

We should leave it as it is. For example, if |status| is equal to
|MEDIA_CODEC_OUTPUT_END_OF_STREAM|, then changing the |status| to OK
will let MSP think that video still hasn't finished.

On 2014/05/21 00:48:04, wolenetz wrote:

+    ReleaseMediaCodecBridge();
+    release_resources_pending_ = false;
+    if (drain_decoder_)
+      OnDecoderDrained();

[wolenetz, 2014/05/21 00:48:04]

nit: CurrentDataConsumed(...) is called twice if line 535 and 543 are reached in
one path through this method. Would be good to either call out in the method
docs that this is fine, or fix this method to only call it max once per each
OnDecodeCompleted().

[qinmin, 2014/05/22 00:35:55]

OnDecoderDrained（） will set drain_decoder_ to false. So if line 535 is reached,
we will not reach line 543.

On 2014/05/21 00:48:04, wolenetz wrote:

+  }
+
   stop_decode_pending_ = false;
   base::ResetAndReturn(&decode_cb_).Run(
       status, current_presentation_timestamp, max_presentation_timestamp);
@@ -480,16 +568,6 @@ bool MediaDecoderJob::NoAccessUnitsRemainingInChunk(
   return received_data_[index].access_units.size() <= access_unit_index_[index];
 }
 
-void MediaDecoderJob::ClearData() {
-  DCHECK(ui_task_runner_->BelongsToCurrentThread());
-  current_demuxer_data_index_ = 0;
-  InitializeReceivedData();
-  on_data_received_cb_.Reset();
-  if (is_requesting_demuxer_data_)
-    is_incoming_data_invalid_ = true;
-  input_eos_encountered_ = false;
-}
-
 void MediaDecoderJob::RequestCurrentChunkIfEmpty() {
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
   DCHECK(HasData());
@@ -501,7 +579,6 @@ void MediaDecoderJob::RequestCurrentChunkIfEmpty() {
   const AccessUnit last_access_unit =
       received_data_[current_demuxer_data_index_].access_units.back();
   if (!last_access_unit.end_of_stream &&
-      last_access_unit.status != DemuxerStream::kConfigChanged &&
       last_access_unit.status != DemuxerStream::kAborted) {
     RequestData(base::Closure());
   }
@@ -514,4 +591,51 @@ void MediaDecoderJob::InitializeReceivedData() {
   }
 }
 
+void MediaDecoderJob::OnDecoderDrained() {
+  DVLOG(1) << __FUNCTION__;
+  DCHECK(ui_task_runner_->BelongsToCurrentThread());
+  DCHECK(drain_decoder_);
+
+  input_eos_encountered_ = false;
+  output_eos_encountered_ = false;
+  drain_decoder_ = false;
+  ReleaseMediaCodecBridge();
+  // Increase the access unit index so that the new decoder will not handle
+  // the config change again.
+  access_unit_index_[current_demuxer_data_index_]++;
+  CurrentDataConsumed(true);
+}
+
+bool MediaDecoderJob::CreateMediaCodecBridge() {
+  DVLOG(1) << __FUNCTION__;
+  DCHECK(ui_task_runner_->BelongsToCurrentThread());
+  DCHECK(decode_cb_.is_null());
+
+  if (!HasStream()) {
+    ReleaseMediaCodecBridge();
+    return false;
+  }
+
+  // Create |media_codec_bridge_| only if config changes.
+  if (media_codec_bridge_ && !need_to_reconfig_decoder_job_)
+    return true;
+
+  base::android::ScopedJavaLocalRef<jobject> media_crypto = GetMediaCrypto();
+  if (is_content_encrypted_ && media_crypto.is_null())
+    return false;
+
+  ReleaseMediaCodecBridge();
+  DVLOG(1) << __FUNCTION__ << " : creating new media codec bridge";
+
+  return CreateMediaCodecBridgeInternal();
+}
+
+void MediaDecoderJob::ReleaseMediaCodecBridge() {
+  if (!media_codec_bridge_)
+    return;
+
+  media_codec_bridge_.reset();
+  OnMediaCodecBridgeReleased();
+}
+
 }  // namespace media