media/base/android/media_decoder_job.h

   1 // Copyright 2013 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 #ifndef MEDIA_BASE_ANDROID_MEDIA_DECODER_JOB_H_
   6 #define MEDIA_BASE_ANDROID_MEDIA_DECODER_JOB_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/weak_ptr.h"
  10 #include "base/time/time.h"
  11 #include "media/base/android/demuxer_stream_player_params.h"
  12
  13 namespace base {
  14 class MessageLoopProxy;
  15 }
  16
  17 namespace media {
  18
  19 class MediaCodecBridge;
  20
  21 // Class for managing all the decoding tasks. Each decoding task will be posted
  22 // onto the same thread. The thread will be stopped once Stop() is called.
  23 class MediaDecoderJob {
  24  public:
  25   enum DecodeStatus {
  26     DECODE_SUCCEEDED,
  27     DECODE_TRY_ENQUEUE_INPUT_AGAIN_LATER,
  28     DECODE_TRY_DEQUEUE_OUTPUT_AGAIN_LATER,
  29     DECODE_FORMAT_CHANGED,
  30     DECODE_INPUT_END_OF_STREAM,
  31     DECODE_OUTPUT_END_OF_STREAM,
  32     DECODE_FAILED,
  33   };
  34
  35   struct Deleter {
  36     inline void operator()(MediaDecoderJob* ptr) const { ptr->Release(); }
  37   };
  38
  39   virtual ~MediaDecoderJob();
  40
  41   // Callback when a decoder job finishes its work. Args: whether decode
  42   // finished successfully, presentation time, audio output bytes.
  43   typedef base::Callback<void(DecodeStatus, const base::TimeDelta&,
  44                               size_t)> DecoderCallback;
  45
  46   // Called by MediaSourcePlayer to decode some data.
  47   void Decode(const AccessUnit& unit,
  48               const base::TimeTicks& start_time_ticks,
  49               const base::TimeDelta& start_presentation_timestamp,
  50               const MediaDecoderJob::DecoderCallback& callback);
  51
  52   // Flush the decoder.
  53   void Flush();
  54
  55   // Called on the UI thread to indicate that one decode cycle has completed.
  56   void OnDecodeCompleted();
  57
  58   bool is_decoding() const { return is_decoding_; }
  59
  60  protected:
  61   MediaDecoderJob(const scoped_refptr<base::MessageLoopProxy>& decoder_loop,
  62                   MediaCodecBridge* media_codec_bridge);
  63
  64   // Release the output buffer and render it.
  65   virtual void ReleaseOutputBuffer(
  66       int outputBufferIndex, size_t size,
  67       const base::TimeDelta& presentation_timestamp,
  68       const MediaDecoderJob::DecoderCallback& callback,
  69       DecodeStatus status) = 0;
  70
  71   // Returns true if the "time to render" needs to be computed for frames in
  72   // this decoder job.
  73   virtual bool ComputeTimeToRender() const = 0;
  74
  75  private:
  76   // Causes this instance to be deleted on the thread it is bound to.
  77   void Release();
  78
  79   DecodeStatus QueueInputBuffer(const AccessUnit& unit);
  80
  81   // Helper function to decoder data on |thread_|. |unit| contains all the data
  82   // to be decoded. |start_time_ticks| and |start_presentation_timestamp|
  83   // represent the system time and the presentation timestamp when the first
  84   // frame is rendered. We use these information to estimate when the current
  85   // frame should be rendered. If |needs_flush| is true, codec needs to be
  86   // flushed at the beginning of this call.
  87   void DecodeInternal(const AccessUnit& unit,
  88                       const base::TimeTicks& start_time_ticks,
  89                       const base::TimeDelta& start_presentation_timestamp,
  90                       bool needs_flush,
  91                       const MediaDecoderJob::DecoderCallback& callback);
  92
  93   // The UI message loop where callbacks should be dispatched.
  94   scoped_refptr<base::MessageLoopProxy> ui_loop_;
  95
  96   // The message loop that decoder job runs on.
  97   scoped_refptr<base::MessageLoopProxy> decoder_loop_;
  98
  99   // The media codec bridge used for decoding. Owned by derived class.
 100   // NOTE: This MUST NOT be accessed in the destructor.
 101   MediaCodecBridge* media_codec_bridge_;
 102
 103   // Whether the decoder needs to be flushed.
 104   bool needs_flush_;
 105
 106   // Whether input EOS is encountered.
 107   bool input_eos_encountered_;
 108
 109   // Weak pointer passed to media decoder jobs for callbacks. It is bounded to
 110   // the decoder thread.
 111   base::WeakPtrFactory<MediaDecoderJob> weak_this_;
 112
 113   // Whether the decoder is actively decoding data.
 114   bool is_decoding_;
 115
 116   DISALLOW_IMPLICIT_CONSTRUCTORS(MediaDecoderJob);
 117 };
 118
 119 }  // namespace media
 120
 121 #endif  // MEDIA_BASE_ANDROID_MEDIA_DECODER_JOB_H_