media/base/android/media_codec_decoder.cc

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/base/android/media_codec_decoder.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/callback_helpers.h"
  10 #include "base/logging.h"
  11 #include "media/base/android/media_codec_bridge.h"
  12
  13 namespace media {
  14
  15 namespace {
  16
  17 // Stop requesting new data in the kPrefetching state when the queue size
  18 // reaches this limit.
  19 const int kPrefetchLimit = 8;
  20
  21 // Request new data in the kRunning state if the queue size is less than this.
  22 const int kPlaybackLowLimit = 4;
  23
  24 // Posting delay of the next frame processing, in milliseconds
  25 const int kNextFrameDelay = 1;
  26
  27 // Timeout for dequeuing an input buffer from MediaCodec in milliseconds.
  28 const int kInputBufferTimeout = 20;
  29
  30 // Timeout for dequeuing an output buffer from MediaCodec in milliseconds.
  31 const int kOutputBufferTimeout = 20;
  32 }
  33
  34 MediaCodecDecoder::MediaCodecDecoder(
  35     const scoped_refptr<base::SingleThreadTaskRunner>& media_task_runner,
  36     const base::Closure& external_request_data_cb,
  37     const base::Closure& starvation_cb,
  38     const base::Closure& stop_done_cb,
  39     const base::Closure& error_cb,
  40     const char* decoder_thread_name)
  41     : media_task_runner_(media_task_runner),
  42       decoder_thread_(decoder_thread_name),
  43       needs_reconfigure_(false),
  44       external_request_data_cb_(external_request_data_cb),
  45       starvation_cb_(starvation_cb),
  46       stop_done_cb_(stop_done_cb),
  47       error_cb_(error_cb),
  48       state_(kStopped),
  49       eos_enqueued_(false),
  50       completed_(false),
  51       last_frame_posted_(false),
  52       is_data_request_in_progress_(false),
  53       is_incoming_data_invalid_(false),
  54 #ifndef NDEBUG
  55       verify_next_frame_is_key_(false),
  56 #endif
  57       weak_factory_(this) {
  58   DCHECK(media_task_runner_->BelongsToCurrentThread());
  59
  60   DVLOG(1) << "Decoder::Decoder() " << decoder_thread_name;
  61
  62   internal_error_cb_ =
  63       base::Bind(&MediaCodecDecoder::OnCodecError, weak_factory_.GetWeakPtr());
  64   request_data_cb_ =
  65       base::Bind(&MediaCodecDecoder::RequestData, weak_factory_.GetWeakPtr());
  66 }
  67
  68 MediaCodecDecoder::~MediaCodecDecoder() {
  69   DCHECK(media_task_runner_->BelongsToCurrentThread());
  70
  71   DVLOG(1) << "Decoder::~Decoder()";
  72
  73   // NB: ReleaseDecoderResources() is virtual
  74   ReleaseDecoderResources();
  75 }
  76
  77 const char* MediaCodecDecoder::class_name() const {
  78   return "Decoder";
  79 }
  80
  81 void MediaCodecDecoder::ReleaseDecoderResources() {
  82   DCHECK(media_task_runner_->BelongsToCurrentThread());
  83
  84   DVLOG(1) << class_name() << "::" << __FUNCTION__;
  85
  86   // Set [kInEmergencyStop| state to block already posted ProcessNextFrame().
  87   SetState(kInEmergencyStop);
  88
  89   decoder_thread_.Stop();  // synchronous
  90
  91   SetState(kStopped);
  92   media_codec_bridge_.reset();
  93 }
  94
  95 void MediaCodecDecoder::Flush() {
  96   DCHECK(media_task_runner_->BelongsToCurrentThread());
  97
  98   DVLOG(1) << class_name() << "::" << __FUNCTION__;
  99
 100   DCHECK_EQ(GetState(), kStopped);
 101
 102   // Flush() is a part of the Seek request. Whenever we request a seek we need
 103   // to invalidate the current data request.
 104   if (is_data_request_in_progress_)
 105     is_incoming_data_invalid_ = true;
 106
 107   eos_enqueued_ = false;
 108   completed_ = false;
 109   au_queue_.Flush();
 110
 111 #ifndef NDEBUG
 112   // We check and reset |verify_next_frame_is_key_| on Decoder thread.
 113   // This DCHECK ensures we won't need to lock this variable.
 114   DCHECK(!decoder_thread_.IsRunning());
 115
 116   // For video the first frame after flush must be key frame.
 117   verify_next_frame_is_key_ = true;
 118 #endif
 119
 120   if (media_codec_bridge_) {
 121     // MediaCodecBridge::Reset() performs MediaCodecBridge.flush()
 122     MediaCodecStatus flush_status = media_codec_bridge_->Reset();
 123     if (flush_status != MEDIA_CODEC_OK) {
 124       DVLOG(0) << class_name() << "::" << __FUNCTION__
 125                << "MediaCodecBridge::Reset() failed";
 126       media_task_runner_->PostTask(FROM_HERE, internal_error_cb_);
 127     }
 128   }
 129 }
 130
 131 void MediaCodecDecoder::ReleaseMediaCodec() {
 132   DCHECK(media_task_runner_->BelongsToCurrentThread());
 133
 134   DVLOG(1) << class_name() << "::" << __FUNCTION__;
 135
 136   media_codec_bridge_.reset();
 137 }
 138
 139 bool MediaCodecDecoder::IsPrefetchingOrPlaying() const {
 140   DCHECK(media_task_runner_->BelongsToCurrentThread());
 141
 142   base::AutoLock lock(state_lock_);
 143   return state_ == kPrefetching || state_ == kRunning;
 144 }
 145
 146 bool MediaCodecDecoder::IsStopped() const {
 147   DCHECK(media_task_runner_->BelongsToCurrentThread());
 148
 149   return GetState() == kStopped;
 150 }
 151
 152 bool MediaCodecDecoder::IsCompleted() const {
 153   DCHECK(media_task_runner_->BelongsToCurrentThread());
 154
 155   return completed_;
 156 }
 157
 158 base::android::ScopedJavaLocalRef<jobject> MediaCodecDecoder::GetMediaCrypto() {
 159   base::android::ScopedJavaLocalRef<jobject> media_crypto;
 160
 161   // TODO(timav): implement DRM.
 162   // drm_bridge_ is not implemented
 163   // if (drm_bridge_)
 164   //   media_crypto = drm_bridge_->GetMediaCrypto();
 165   return media_crypto;
 166 }
 167
 168 void MediaCodecDecoder::Prefetch(const base::Closure& prefetch_done_cb) {
 169   DCHECK(media_task_runner_->BelongsToCurrentThread());
 170
 171   DVLOG(1) << class_name() << "::" << __FUNCTION__;
 172
 173   DCHECK(GetState() == kStopped);
 174
 175   prefetch_done_cb_ = prefetch_done_cb;
 176
 177   SetState(kPrefetching);
 178   PrefetchNextChunk();
 179 }
 180
 181 MediaCodecDecoder::ConfigStatus MediaCodecDecoder::Configure() {
 182   DCHECK(media_task_runner_->BelongsToCurrentThread());
 183
 184   DVLOG(1) << class_name() << "::" << __FUNCTION__;
 185
 186   if (GetState() == kError) {
 187     DVLOG(0) << class_name() << "::" << __FUNCTION__ << ": wrong state kError";
 188     return kConfigFailure;
 189   }
 190
 191   if (needs_reconfigure_) {
 192     DVLOG(1) << class_name() << "::" << __FUNCTION__
 193              << ": needs reconfigure, deleting MediaCodec";
 194     needs_reconfigure_ = false;
 195     media_codec_bridge_.reset();
 196
 197     // No need to release these buffers since the MediaCodec is deleted, just
 198     // remove their indexes from |delayed_buffers_|.
 199
 200     ClearDelayedBuffers(false);
 201   }
 202
 203   MediaCodecDecoder::ConfigStatus result;
 204   if (media_codec_bridge_) {
 205     DVLOG(1) << class_name() << "::" << __FUNCTION__
 206              << ": reconfiguration is not required, ignoring";
 207     result = kConfigOk;
 208   } else {
 209     result = ConfigureInternal();
 210
 211 #ifndef NDEBUG
 212     // We check and reset |verify_next_frame_is_key_| on Decoder thread.
 213     // This DCHECK ensures we won't need to lock this variable.
 214     DCHECK(!decoder_thread_.IsRunning());
 215
 216     // For video the first frame after reconfiguration must be key frame.
 217     if (result == kConfigOk)
 218       verify_next_frame_is_key_ = true;
 219 #endif
 220   }
 221
 222   return result;
 223 }
 224
 225 bool MediaCodecDecoder::Start(base::TimeDelta current_time) {
 226   DCHECK(media_task_runner_->BelongsToCurrentThread());
 227
 228   DVLOG(1) << class_name() << "::" << __FUNCTION__
 229            << " current_time:" << current_time;
 230
 231   DecoderState state = GetState();
 232   if (state == kRunning) {
 233     DVLOG(1) << class_name() << "::" << __FUNCTION__ << ": already started";
 234     return true;  // already started
 235   }
 236
 237   if (state != kPrefetched) {
 238     DVLOG(0) << class_name() << "::" << __FUNCTION__ << ": wrong state "
 239              << AsString(state) << ", ignoring";
 240     return false;
 241   }
 242
 243   if (!media_codec_bridge_) {
 244     DVLOG(0) << class_name() << "::" << __FUNCTION__
 245              << ": not configured, ignoring";
 246     return false;
 247   }
 248
 249   DCHECK(!decoder_thread_.IsRunning());
 250
 251   // We only synchronize video stream.
 252   // When audio is present, the |current_time| is audio time.
 253   SynchronizePTSWithTime(current_time);
 254
 255   last_frame_posted_ = false;
 256
 257   // Start the decoder thread
 258   if (!decoder_thread_.Start()) {
 259     DVLOG(1) << class_name() << "::" << __FUNCTION__
 260              << ": cannot start decoder thread";
 261     return false;
 262   }
 263
 264   SetState(kRunning);
 265
 266   decoder_thread_.task_runner()->PostTask(
 267       FROM_HERE,
 268       base::Bind(&MediaCodecDecoder::ProcessNextFrame, base::Unretained(this)));
 269
 270   return true;
 271 }
 272
 273 void MediaCodecDecoder::SyncStop() {
 274   DCHECK(media_task_runner_->BelongsToCurrentThread());
 275
 276   DVLOG(1) << class_name() << "::" << __FUNCTION__;
 277
 278   if (GetState() == kError) {
 279     DVLOG(0) << class_name() << "::" << __FUNCTION__
 280              << ": wrong state kError, ignoring";
 281     return;
 282   }
 283
 284   // After this method returns, decoder thread will not be running.
 285
 286   // Set [kInEmergencyStop| state to block already posted ProcessNextFrame().
 287   SetState(kInEmergencyStop);
 288
 289   decoder_thread_.Stop();  // synchronous
 290
 291   SetState(kStopped);
 292
 293   ClearDelayedBuffers(true);  // release prior to clearing  |delayed_buffers_|.
 294 }
 295
 296 void MediaCodecDecoder::RequestToStop() {
 297   DCHECK(media_task_runner_->BelongsToCurrentThread());
 298
 299   DVLOG(1) << class_name() << "::" << __FUNCTION__;
 300
 301   DecoderState state = GetState();
 302   switch (state) {
 303     case kError:
 304       DVLOG(0) << class_name() << "::" << __FUNCTION__
 305                << ": wrong state kError, ignoring";
 306       break;
 307     case kRunning:
 308       SetState(kStopping);
 309       break;
 310     case kStopping:
 311       break;  // ignore
 312     case kStopped:
 313     case kPrefetching:
 314     case kPrefetched:
 315       // There is nothing to wait for, we can sent nofigication right away.
 316       DCHECK(!decoder_thread_.IsRunning());
 317       SetState(kStopped);
 318       media_task_runner_->PostTask(FROM_HERE, stop_done_cb_);
 319       break;
 320     default:
 321       NOTREACHED();
 322       break;
 323   }
 324 }
 325
 326 void MediaCodecDecoder::OnLastFrameRendered(bool completed) {
 327   DCHECK(media_task_runner_->BelongsToCurrentThread());
 328
 329   DVLOG(1) << class_name() << "::" << __FUNCTION__
 330            << " completed:" << completed;
 331
 332   decoder_thread_.Stop();  // synchronous
 333
 334   SetState(kStopped);
 335   completed_ = completed;
 336
 337   media_task_runner_->PostTask(FROM_HERE, stop_done_cb_);
 338 }
 339
 340 void MediaCodecDecoder::OnDemuxerDataAvailable(const DemuxerData& data) {
 341   DCHECK(media_task_runner_->BelongsToCurrentThread());
 342
 343   // If |data| contains an aborted data, the last AU will have kAborted status.
 344   bool aborted_data =
 345       !data.access_units.empty() &&
 346       data.access_units.back().status == DemuxerStream::kAborted;
 347
 348 #ifndef NDEBUG
 349   const char* explain_if_skipped =
 350       is_incoming_data_invalid_ ? " skipped as invalid"
 351                                 : (aborted_data ? " skipped as aborted" : "");
 352
 353   for (const auto& unit : data.access_units)
 354     DVLOG(2) << class_name() << "::" << __FUNCTION__ << explain_if_skipped
 355              << " au: " << unit;
 356   for (const auto& configs : data.demuxer_configs)
 357     DVLOG(2) << class_name() << "::" << __FUNCTION__ << " configs: " << configs;
 358 #endif
 359
 360   if (!is_incoming_data_invalid_ && !aborted_data)
 361     au_queue_.PushBack(data);
 362
 363   is_incoming_data_invalid_ = false;
 364   is_data_request_in_progress_ = false;
 365
 366   // Do not request data if we got kAborted. There is no point to request the
 367   // data after kAborted and before the OnDemuxerSeekDone.
 368   if (GetState() == kPrefetching && !aborted_data)
 369     PrefetchNextChunk();
 370 }
 371
 372 int MediaCodecDecoder::NumDelayedRenderTasks() const {
 373   return 0;
 374 }
 375
 376 void MediaCodecDecoder::CheckLastFrame(bool eos_encountered,
 377                                        bool has_delayed_tasks) {
 378   DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
 379
 380   bool last_frame_when_stopping = GetState() == kStopping && !has_delayed_tasks;
 381
 382   if (last_frame_when_stopping || eos_encountered) {
 383     media_task_runner_->PostTask(
 384         FROM_HERE, base::Bind(&MediaCodecDecoder::OnLastFrameRendered,
 385                               weak_factory_.GetWeakPtr(), eos_encountered));
 386     last_frame_posted_ = true;
 387   }
 388 }
 389
 390 void MediaCodecDecoder::OnCodecError() {
 391   DCHECK(media_task_runner_->BelongsToCurrentThread());
 392
 393   // Ignore codec errors from the moment surface is changed till the
 394   // |media_codec_bridge_| is deleted.
 395   if (needs_reconfigure_) {
 396     DVLOG(1) << class_name() << "::" << __FUNCTION__
 397              << ": needs reconfigure, ignoring";
 398     return;
 399   }
 400
 401   SetState(kError);
 402   error_cb_.Run();
 403 }
 404
 405 void MediaCodecDecoder::RequestData() {
 406   DCHECK(media_task_runner_->BelongsToCurrentThread());
 407
 408   // Ensure one data request at a time.
 409   if (!is_data_request_in_progress_) {
 410     is_data_request_in_progress_ = true;
 411     external_request_data_cb_.Run();
 412   }
 413 }
 414
 415 void MediaCodecDecoder::PrefetchNextChunk() {
 416   DCHECK(media_task_runner_->BelongsToCurrentThread());
 417
 418   DVLOG(1) << class_name() << "::" << __FUNCTION__;
 419
 420   AccessUnitQueue::Info au_info = au_queue_.GetInfo();
 421
 422   if (eos_enqueued_ || au_info.length >= kPrefetchLimit || au_info.has_eos) {
 423     // We are done prefetching
 424     SetState(kPrefetched);
 425     DVLOG(1) << class_name() << "::" << __FUNCTION__ << " posting PrefetchDone";
 426     media_task_runner_->PostTask(FROM_HERE,
 427                                  base::ResetAndReturn(&prefetch_done_cb_));
 428     return;
 429   }
 430
 431   request_data_cb_.Run();
 432 }
 433
 434 void MediaCodecDecoder::ProcessNextFrame() {
 435   DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
 436
 437   DVLOG(2) << class_name() << "::" << __FUNCTION__;
 438
 439   DecoderState state = GetState();
 440
 441   if (state != kRunning && state != kStopping) {
 442     DVLOG(1) << class_name() << "::" << __FUNCTION__ << ": not running";
 443     return;
 444   }
 445
 446   if (state == kStopping) {
 447     if (NumDelayedRenderTasks() == 0 && !last_frame_posted_) {
 448       DVLOG(1) << class_name() << "::" << __FUNCTION__
 449                << ": kStopping, posting OnLastFrameRendered";
 450       media_task_runner_->PostTask(
 451           FROM_HERE, base::Bind(&MediaCodecDecoder::OnLastFrameRendered,
 452                                 weak_factory_.GetWeakPtr(), false));
 453       last_frame_posted_ = true;
 454     }
 455
 456     // We can stop processing, the |au_queue_| and MediaCodec queues can freeze.
 457     // We only need to let finish the delayed rendering tasks.
 458     return;
 459   }
 460
 461   DCHECK(state == kRunning);
 462
 463   if (!EnqueueInputBuffer())
 464     return;
 465
 466   if (!DepleteOutputBufferQueue())
 467     return;
 468
 469   // We need a small delay if we want to stop this thread by
 470   // decoder_thread_.Stop() reliably.
 471   // The decoder thread message loop processes all pending
 472   // (but not delayed) tasks before it can quit; without a delay
 473   // the message loop might be forever processing the pendng tasks.
 474   decoder_thread_.task_runner()->PostDelayedTask(
 475       FROM_HERE,
 476       base::Bind(&MediaCodecDecoder::ProcessNextFrame, base::Unretained(this)),
 477       base::TimeDelta::FromMilliseconds(kNextFrameDelay));
 478 }
 479
 480 // Returns false if we should stop decoding process. Right now
 481 // it happens if we got MediaCodec error or detected starvation.
 482 bool MediaCodecDecoder::EnqueueInputBuffer() {
 483   DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
 484
 485   DVLOG(2) << class_name() << "::" << __FUNCTION__;
 486
 487   if (eos_enqueued_) {
 488     DVLOG(1) << class_name() << "::" << __FUNCTION__
 489              << ": eos_enqueued, returning";
 490     return true;  // Nothing to do
 491   }
 492
 493   // Keep the number pending video frames low, ideally maintaining
 494   // the same audio and video duration after stop request
 495   if (NumDelayedRenderTasks() > 1) {
 496     DVLOG(2) << class_name() << "::" << __FUNCTION__ << ": # delayed buffers ("
 497              << NumDelayedRenderTasks() << ") exceeds 1, returning";
 498     return true;  // Nothing to do
 499   }
 500
 501   // Get the next frame from the queue and the queue info
 502
 503   AccessUnitQueue::Info au_info = au_queue_.GetInfo();
 504
 505   // Request the data from Demuxer
 506   if (au_info.length <= kPlaybackLowLimit && !au_info.has_eos)
 507     media_task_runner_->PostTask(FROM_HERE, request_data_cb_);
 508
 509   // Get the next frame from the queue
 510
 511   if (!au_info.length) {
 512     // Report starvation and return, Start() will be called again later.
 513     DVLOG(1) << class_name() << "::" << __FUNCTION__ << ": starvation detected";
 514     media_task_runner_->PostTask(FROM_HERE, starvation_cb_);
 515     return true;
 516   }
 517
 518   if (au_info.configs) {
 519     DVLOG(1) << class_name() << "::" << __FUNCTION__
 520              << ": received new configs, not implemented";
 521     // post an error for now?
 522     media_task_runner_->PostTask(FROM_HERE, internal_error_cb_);
 523     return false;
 524   }
 525
 526   // We are ready to enqueue the front unit.
 527
 528 #ifndef NDEBUG
 529   if (verify_next_frame_is_key_) {
 530     verify_next_frame_is_key_ = false;
 531     VerifyUnitIsKeyFrame(au_info.front_unit);
 532   }
 533 #endif
 534
 535   // Dequeue input buffer
 536
 537   base::TimeDelta timeout =
 538       base::TimeDelta::FromMilliseconds(kInputBufferTimeout);
 539   int index = -1;
 540   MediaCodecStatus status =
 541       media_codec_bridge_->DequeueInputBuffer(timeout, &index);
 542
 543   DVLOG(2) << class_name() << ":: DequeueInputBuffer index:" << index;
 544
 545   switch (status) {
 546     case MEDIA_CODEC_ERROR:
 547       DVLOG(0) << class_name() << "::" << __FUNCTION__
 548                << ": MEDIA_CODEC_ERROR DequeueInputBuffer failed";
 549       media_task_runner_->PostTask(FROM_HERE, internal_error_cb_);
 550       return false;
 551
 552     case MEDIA_CODEC_DEQUEUE_INPUT_AGAIN_LATER:
 553       return true;
 554
 555     default:
 556       break;
 557   }
 558
 559   // We got the buffer
 560   DCHECK_EQ(status, MEDIA_CODEC_OK);
 561   DCHECK_GE(index, 0);
 562
 563   const AccessUnit* unit = au_info.front_unit;
 564   DCHECK(unit);
 565
 566   if (unit->is_end_of_stream) {
 567     DVLOG(1) << class_name() << "::" << __FUNCTION__ << ": QueueEOS";
 568     media_codec_bridge_->QueueEOS(index);
 569     eos_enqueued_ = true;
 570     return true;
 571   }
 572
 573   DVLOG(2) << class_name() << ":: QueueInputBuffer pts:" << unit->timestamp;
 574
 575   status = media_codec_bridge_->QueueInputBuffer(
 576       index, &unit->data[0], unit->data.size(), unit->timestamp);
 577
 578   if (status == MEDIA_CODEC_ERROR) {
 579     DVLOG(0) << class_name() << "::" << __FUNCTION__
 580              << ": MEDIA_CODEC_ERROR: QueueInputBuffer failed";
 581     media_task_runner_->PostTask(FROM_HERE, internal_error_cb_);
 582     return false;
 583   }
 584
 585   // Have successfully queued input buffer, go to next access unit.
 586   au_queue_.Advance();
 587   return true;
 588 }
 589
 590 // Returns false if there was MediaCodec error.
 591 bool MediaCodecDecoder::DepleteOutputBufferQueue() {
 592   DCHECK(decoder_thread_.task_runner()->BelongsToCurrentThread());
 593
 594   DVLOG(2) << class_name() << "::" << __FUNCTION__;
 595
 596   int buffer_index = 0;
 597   size_t offset = 0;
 598   size_t size = 0;
 599   base::TimeDelta pts;
 600   MediaCodecStatus status;
 601   bool eos_encountered = false;
 602
 603   base::TimeDelta timeout =
 604       base::TimeDelta::FromMilliseconds(kOutputBufferTimeout);
 605
 606   // Extract all output buffers that are available.
 607   // Usually there will be only one, but sometimes it is preceeded by
 608   // MEDIA_CODEC_OUTPUT_BUFFERS_CHANGED or MEDIA_CODEC_OUTPUT_FORMAT_CHANGED.
 609   do {
 610     status = media_codec_bridge_->DequeueOutputBuffer(
 611         timeout, &buffer_index, &offset, &size, &pts, &eos_encountered,
 612         nullptr);
 613
 614     // Reset the timeout to 0 for the subsequent DequeueOutputBuffer() calls
 615     // to quickly break the loop after we got all currently available buffers.
 616     timeout = base::TimeDelta::FromMilliseconds(0);
 617
 618     switch (status) {
 619       case MEDIA_CODEC_OUTPUT_BUFFERS_CHANGED:
 620         // Output buffers are replaced in MediaCodecBridge, nothing to do.
 621         break;
 622
 623       case MEDIA_CODEC_OUTPUT_FORMAT_CHANGED:
 624         DVLOG(2) << class_name() << "::" << __FUNCTION__
 625                  << " MEDIA_CODEC_OUTPUT_FORMAT_CHANGED";
 626         OnOutputFormatChanged();
 627         break;
 628
 629       case MEDIA_CODEC_OK:
 630         // We got the decoded frame
 631         Render(buffer_index, size, true, pts, eos_encountered);
 632         break;
 633
 634       case MEDIA_CODEC_DEQUEUE_OUTPUT_AGAIN_LATER:
 635         // Nothing to do.
 636         break;
 637
 638       case MEDIA_CODEC_ERROR:
 639         DVLOG(0) << class_name() << "::" << __FUNCTION__
 640                  << ": MEDIA_CODEC_ERROR from DequeueOutputBuffer";
 641         media_task_runner_->PostTask(FROM_HERE, internal_error_cb_);
 642         break;
 643
 644       default:
 645         NOTREACHED();
 646         break;
 647     }
 648
 649   } while (status != MEDIA_CODEC_DEQUEUE_OUTPUT_AGAIN_LATER &&
 650            status != MEDIA_CODEC_ERROR && !eos_encountered);
 651
 652   if (eos_encountered) {
 653     DVLOG(1) << class_name() << "::" << __FUNCTION__
 654              << " EOS dequeued, stopping frame processing";
 655     return false;
 656   }
 657
 658   if (status == MEDIA_CODEC_ERROR) {
 659     DVLOG(1) << class_name() << "::" << __FUNCTION__
 660              << " MediaCodec error, stopping frame processing";
 661     return false;
 662   }
 663
 664   return true;
 665 }
 666
 667 MediaCodecDecoder::DecoderState MediaCodecDecoder::GetState() const {
 668   base::AutoLock lock(state_lock_);
 669   return state_;
 670 }
 671
 672 void MediaCodecDecoder::SetState(DecoderState state) {
 673   DVLOG(1) << class_name() << "::" << __FUNCTION__ << " " << AsString(state);
 674
 675   base::AutoLock lock(state_lock_);
 676   state_ = state;
 677 }
 678
 679 #undef RETURN_STRING
 680 #define RETURN_STRING(x) \
 681   case x:                \
 682     return #x;
 683
 684 const char* MediaCodecDecoder::AsString(DecoderState state) {
 685   switch (state) {
 686     RETURN_STRING(kStopped);
 687     RETURN_STRING(kPrefetching);
 688     RETURN_STRING(kPrefetched);
 689     RETURN_STRING(kRunning);
 690     RETURN_STRING(kStopping);
 691     RETURN_STRING(kInEmergencyStop);
 692     RETURN_STRING(kError);
 693     default:
 694       return "Unknown DecoderState";
 695   }
 696 }
 697
 698 #undef RETURN_STRING
 699
 700 }  // namespace media