Implementation of MediaCodecPlayer stage 1

media/base/android/media_codec_decoder.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/base/android/media_codec_decoder.h"
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/callback_helpers.h"
+#include "base/logging.h"
+#include "media/base/android/media_codec_bridge.h"
+
+namespace media {
+
+namespace {
+
+// Stop requesting new data in the PREFETCH state when the queue size reaches
+// this limit.
+const int kPrefetchLimit = 8;
+
+// Request new data in the RUNNING state if the queue size is less than this.
+const int kPlaybackLowLimit = 4;
+
+// Posting delay of the next frame processing, in milliseconds
+const int kNextFrameDelay = 2;
+
+// Timeout for dequeuing an input buffer from MediaCodec in milliseconds.
+const int kInputBufferTimeout = 20;
+
+// Timeout for dequeuing an output buffer from MediaCodec in milliseconds.
+const int kOutputBufferTimeout = 20;
+}
+
+MediaCodecDecoder::MediaCodecDecoder(
+    const scoped_refptr<base::SingleThreadTaskRunner>& media_task_runner,
+    const base::Closure& request_data_cb,
+    const base::Closure& starvation_cb,
+    const base::Closure& stop_done_cb,
+    const base::Closure& error_cb,
+    const char* decoder_thread_name)
+    : media_task_runner_(media_task_runner),
+      decoder_thread_(decoder_thread_name),
+      request_data_cb_(request_data_cb),
+      starvation_cb_(starvation_cb),
+      stop_done_cb_(stop_done_cb),
+      error_cb_(error_cb),
+      state_(STOPPED),
+      eos_enqueued_(false),
+      completed_(false),
+      last_frame_posted_(false),
+      weak_factory_(this) {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << "Decoder::Decoder() " << decoder_thread_name;
+
+  weak_this_ = weak_factory_.GetWeakPtr();
+}
+
+MediaCodecDecoder::~MediaCodecDecoder() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << "Decoder::~Decoder()";
+
+  // NB: ReleaseDecoderResources() is virtual
+  ReleaseDecoderResources();
+}
+
+void MediaCodecDecoder::ReleaseDecoderResources() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  decoder_thread_.Stop(); // synchronous
+  state_ = STOPPED;
+  media_codec_bridge_.reset();
+}
+
+void MediaCodecDecoder::Flush() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  DCHECK_EQ(GetState(), STOPPED);
+
+  eos_enqueued_ = false;
+  completed_ = false;
+  au_queue_.Flush();
+
+  if (media_codec_bridge_) {
+    // MediaCodecBridge::Reset() performs MediaCodecBridge.flush()
+    MediaCodecStatus flush_status = media_codec_bridge_->Reset();
+    if (flush_status != MEDIA_CODEC_OK)
+      media_task_runner_->PostTask(FROM_HERE, error_cb_);
+  }
+}
+
+void MediaCodecDecoder::ReleaseMediaCodec() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  media_codec_bridge_.reset();
+}
+
+bool MediaCodecDecoder::IsPrefetchingOrPlaying() const {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  base::AutoLock lock(state_lock_);
+  return state_ == PREFETCHING || state_ == RUNNING;
+}
+
+bool MediaCodecDecoder::IsStopped() const {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  return GetState() == STOPPED;
+}
+
+bool MediaCodecDecoder::IsCompleted() const {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  return completed_;
+}
+
+base::android::ScopedJavaLocalRef<jobject>
+MediaCodecDecoder::GetMediaCrypto() {
+  base::android::ScopedJavaLocalRef<jobject> media_crypto;
+
+  // drm_bridge_ is not implemented
+  // if (drm_bridge_)
+  //   media_crypto = drm_bridge_->GetMediaCrypto();
+  return media_crypto;
+}
+
+void MediaCodecDecoder::Prefetch(const base::Closure& prefetch_done_cb) {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  DCHECK(GetState() == STOPPED);
+
+  prefetch_done_cb_ = prefetch_done_cb;
+
+  SetState(PREFETCHING);
+  PrefetchNextChunk();
+}
+
+MediaCodecDecoder::ConfigStatus MediaCodecDecoder::Configure() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  // Here I assume that OnDemuxerConfigsAvailable won't come
+  // in the middle of demuxer data.
+
+  if (media_codec_bridge_) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__
+             << ": reconfiguration is not required, ignoring";
+    return CONFIG_OK;
+  }
+
+  return ConfigureInternal();
+}
+
+bool MediaCodecDecoder::Start(base::TimeDelta current_time) {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__
+           << " current_time:" << current_time;
+
+  if (state_ == RUNNING) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__ << ": already started";
+    return true; // already started
+  }
+
+  if (state_ == STOPPING) {
+    DVLOG(0) << class_name() << "::" << __FUNCTION__
+             << ": wrong state STOPPING, ignoring";
+    return false;
+  }
+
+  DCHECK(!decoder_thread_.IsRunning());
+
+  // We only synchronize video stream.
+  // When audio is present, the |current_time| is audio time.
+  SynchronizePTSWithTime(current_time);
+
+  last_frame_posted_ = false;
+
+  // Start the decoder thread
+  if (!decoder_thread_.Start()) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__
+             << ": cannot start decoder thread";
+    return false;
+  }
+
+  SetState(RUNNING);
+
+  decoder_thread_.task_runner()->PostTask(
+      FROM_HERE,
+      base::Bind(&MediaCodecDecoder::ProcessNextFrame, base::Unretained(this)));
+
+  return true;
+}
+
+void MediaCodecDecoder::SyncStop() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  // After this method returns, decoder thread will not be running.
+
+  decoder_thread_.Stop(); // synchronous
+  state_ = STOPPED;
+
+  // Shall we move |delayed_buffers_| from VideoDecoder to Decoder class?
+  ReleaseDelayedBuffers();
+}
+
+void MediaCodecDecoder::RequestToStop() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  DCHECK(GetState() == RUNNING);
+  SetState(STOPPING);
+}
+
+void MediaCodecDecoder::OnLastFrameRendered(bool completed) {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__
+           << " completed:" << completed;
+
+  decoder_thread_.Stop(); // synchronous
+  state_ = STOPPED;
+  completed_ = completed;
+
+  media_task_runner_->PostTask(FROM_HERE, stop_done_cb_);
+}
+
+void MediaCodecDecoder::OnDemuxerDataAvailable(const DemuxerData& data) {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(2) << class_name() << "::" << __FUNCTION__
+           << " #AUs:" << data.access_units.size()
+           << " #Configs:" << data.demuxer_configs.size();
+#if !defined(NDEBUG)
+    for (const auto& unit : data.access_units)
+      DVLOG(2) << class_name() << "::" << __FUNCTION__ << " au: " << unit;
+#endif
+
+  au_queue_.PushBack(data);
+
+  if (state_ == PREFETCHING)
+    PrefetchNextChunk();
+}
+
+void MediaCodecDecoder::CheckLastFrame(bool eos_encountered,
+                                       bool has_delayed_tasks) {
+  DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
+
+  bool last_frame_when_stopping =
+      GetState() == STOPPING && !has_delayed_tasks;
+
+  if (last_frame_when_stopping || eos_encountered) {
+    media_task_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&MediaCodecDecoder::OnLastFrameRendered,
+                   weak_this_, eos_encountered));
+    last_frame_posted_ = true;
+  }
+}
+
+void MediaCodecDecoder::PrefetchNextChunk() {
+  DCHECK(media_task_runner_->BelongsToCurrentThread());
+
+  DVLOG(1) << class_name() << "::" << __FUNCTION__;
+
+  AccessUnitQueue::Info au_info = au_queue_.GetInfo();
+
+  if (eos_enqueued_ || au_info.length >= kPrefetchLimit || au_info.has_eos) {
+    // We are done prefetching
+    DVLOG(1) << class_name() << "::" << __FUNCTION__ << " posting PrefetchDone";
+    media_task_runner_->PostTask(
+        FROM_HERE, base::ResetAndReturn(&prefetch_done_cb_));
+    return;
+  }
+
+  request_data_cb_.Run();
+}
+
+void MediaCodecDecoder::ProcessNextFrame() {
+  DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
+
+  DVLOG(2) << class_name() << "::" << __FUNCTION__;
+
+  DecoderState state = GetState();
+
+  if (state != RUNNING && state != STOPPING) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__ << ": not running";
+    return;
+  }
+
+  if (state == STOPPING) {
+    if (NumDelayedRenderTasks() == 0 && !last_frame_posted_) {
+      DVLOG(1) << class_name() << "::" << __FUNCTION__
+               << ": STOPPING, posting OnLastFrameRendered";
+      media_task_runner_->PostTask(
+          FROM_HERE,
+          base::Bind(&MediaCodecDecoder::OnLastFrameRendered,
+                     weak_this_, false));
+      last_frame_posted_ = true;
+    }
+
+    // We can stop processing, the |au_queue_| and MediaCodec queues can freeze.
+    // We only need to let finish the delayed rendering tasks.
+    return;
+  }
+
+  DCHECK(state == RUNNING);
+
+  // Keep the number pending video frames low, ideally maintaining
+  // the same audio and video duration after stop request
+
+  if (NumDelayedRenderTasks() <= 1) {
+    if (!EnqueueInputBuffer())
+      return;
+  }
+
+  bool eos_encountered = false;
+  if (!DepleteOutputBufferQueue(&eos_encountered))
+    return;
+
+  if (eos_encountered) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__
+             << " EOS dequeued, stopping frame processing";
+    return;
+  }
+
+  // We need a small delay if we want to stop this thread by
+  // decoder_thread_.Stop() reliably.
+  // The decoder thread message loop processes all pending
+  // (but not delayed) tasks before it can quit; without a delay
+  // the message loop might be forever processing the pendng tasks.
+  decoder_thread_.task_runner()->PostDelayedTask(

[liberato (no reviews please), 2015/06/09 15:44:30]

alternatively, could we just not post if state_==STOP (modulo thread safety).

[Tima Vaisburd, 2015/06/09 17:38:27]

I did this to support SyncStop() in any state. SyncStop() is called from player
when I did not see the reason to wait, e.g. in destructor or Release() or error.

+      FROM_HERE,
+      base::Bind(&MediaCodecDecoder::ProcessNextFrame,
+                 base::Unretained(this)),
+      base::TimeDelta::FromMilliseconds(kNextFrameDelay));
+}
+
+// Returns false if there was MediaCodec error.
+bool MediaCodecDecoder::EnqueueInputBuffer() {
+  DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
+
+  DVLOG(2) << class_name() << "::" << __FUNCTION__;
+
+  if (eos_enqueued_) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__
+             << ": eos_enqueued, returning";
+    return true; // Nothing to do
+  }
+
+  // Get the next frame from the queue and the queue info
+
+  AccessUnitQueue::Info au_info = au_queue_.GetInfo();
+
+  // Request the data from Demuxer
+  if (au_info.length <= kPlaybackLowLimit && !au_info.has_eos)
+    media_task_runner_->PostTask(FROM_HERE, request_data_cb_);
+
+  // Get the next frame from the queue
+
+  if (!au_info.length) {
+    // Report starvation and return, Start() will be called again later.
+    DVLOG(1) << class_name() << "::" << __FUNCTION__
+             << ": starvation detected";
+    media_task_runner_->PostTask(FROM_HERE, starvation_cb_);
+    return true;
+  }
+
+  if (au_info.configs) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__
+             << ": received new configs, not implemented";
+    // post an error for now?
+    media_task_runner_->PostTask(FROM_HERE, error_cb_);
+    return true;
+  }
+
+  // Dequeue input buffer
+
+  base::TimeDelta timeout =
+      base::TimeDelta::FromMilliseconds(kInputBufferTimeout);
+  int index = -1;
+  MediaCodecStatus status =
+      media_codec_bridge_->DequeueInputBuffer(timeout, &index);
+
+  DVLOG(2) << class_name() << ":: DequeueInputBuffer index:" << index;
+
+  switch (status) {
+    case MEDIA_CODEC_ERROR:
+      DVLOG(0) << class_name() << "::" << __FUNCTION__
+               << ": MEDIA_CODEC_ERROR DequeueInputBuffer failed";
+      media_task_runner_->PostTask(FROM_HERE, error_cb_);
+      return false;
+
+    case MEDIA_CODEC_DEQUEUE_INPUT_AGAIN_LATER:
+      return true;
+
+    default:
+      break;
+  }
+
+  // We got the buffer
+  DCHECK_EQ(status, MEDIA_CODEC_OK);
+  DCHECK_GE(index, 0);
+
+  const AccessUnit* unit = au_info.front_unit;
+  DCHECK(unit);
+
+  if (unit->is_end_of_stream) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__ << ": QueueEOS";
+    media_codec_bridge_->QueueEOS(index);
+    eos_enqueued_ = true;
+    return true;
+  }
+
+  status = media_codec_bridge_->QueueInputBuffer(
+      index, &unit->data[0], unit->data.size(), unit->timestamp);
+
+  if (status == MEDIA_CODEC_ERROR) {
+    DVLOG(1) << class_name() << "::" << __FUNCTION__
+             << ": MEDIA_CODEC_ERROR: QueueInputBuffer failed";
+    media_task_runner_->PostTask(FROM_HERE, error_cb_);
+    return false;
+  }
+
+  // Have successfully queued input buffer, go to next access unit.
+  au_queue_.Advance();
+  return true;
+}
+
+// Returns false if there was MediaCodec error.
+bool MediaCodecDecoder::DepleteOutputBufferQueue(bool* eos_encountered) {
+  DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
+
+  DVLOG(2) << class_name() << "::" << __FUNCTION__;
+
+  int buffer_index = 0;
+  size_t offset = 0;
+  size_t size = 0;
+  base::TimeDelta pts;
+  MediaCodecStatus status;
+
+  base::TimeDelta timeout =
+      base::TimeDelta::FromMilliseconds(kOutputBufferTimeout);
+
+  // Extract all output buffers that are available.
+  // Usually there will be only one, but sometimes it is preceeded by
+  // MEDIA_CODEC_OUTPUT_BUFFERS_CHANGED or MEDIA_CODEC_OUTPUT_FORMAT_CHANGED.
+  do {
+    status = media_codec_bridge_->DequeueOutputBuffer(
+        timeout,
+        &buffer_index,
+        &offset,
+        &size,
+        &pts,
+        eos_encountered,
+        nullptr);
+
+    // Reset the timeout to 0 for the subsequent DequeueOutputBuffer() calls
+    // to quickly break the loop after we got all currently available buffers.
+    timeout = base::TimeDelta::FromMilliseconds(0);
+
+    switch (status) {
+      case MEDIA_CODEC_OUTPUT_BUFFERS_CHANGED:
+        // Output buffers are replaced in MediaCodecBridge, nothing to do.
+        break;
+
+      case MEDIA_CODEC_OUTPUT_FORMAT_CHANGED:
+        DVLOG(2) << class_name() << "::" << __FUNCTION__
+                 << " MEDIA_CODEC_OUTPUT_FORMAT_CHANGED";
+        OnOutputFormatChanged();
+        break;
+
+      case MEDIA_CODEC_OK:
+        // We got the decoded frame
+        Render(buffer_index, size, true, pts, *eos_encountered);
+        break;
+
+      case MEDIA_CODEC_DEQUEUE_OUTPUT_AGAIN_LATER:
+        // Nothing to do.
+        break;
+
+      case MEDIA_CODEC_ERROR:
+        DVLOG(0) << class_name() << "::" << __FUNCTION__
+                 << ": MEDIA_CODEC_ERROR from DequeueOutputBuffer";
+        media_task_runner_->PostTask(FROM_HERE, error_cb_);
+        break;
+
+      default:
+        NOTREACHED();
+        break;
+    }
+
+  } while (status != MEDIA_CODEC_DEQUEUE_OUTPUT_AGAIN_LATER &&
+           status != MEDIA_CODEC_ERROR &&
+           !*eos_encountered);
+
+  return status != MEDIA_CODEC_ERROR;
+}
+
+MediaCodecDecoder::DecoderState MediaCodecDecoder::GetState() const {
+  base::AutoLock lock(state_lock_);
+  return state_;
+}
+
+void MediaCodecDecoder::SetState(DecoderState state) {
+  DVLOG(1) << class_name() << "::" << __FUNCTION__ << " " << state;
+
+  base::AutoLock lock(state_lock_);
+  state_ = state;
+}
+
+}  // namespace media