| // Copyright (c) 2012 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. |
| |
| #ifndef MEDIA_BASE_AUDIO_DECODER_H_ |
| #define MEDIA_BASE_AUDIO_DECODER_H_ |
| |
| #include "base/callback.h" |
| #include "base/memory/ref_counted.h" |
| #include "media/base/audio_decoder_config.h" |
| #include "media/base/channel_layout.h" |
| #include "media/base/decoder_buffer.h" |
| #include "media/base/media_export.h" |
| #include "media/base/pipeline_status.h" |
| |
| namespace media { |
| |
| class AudioBuffer; |
| class DemuxerStream; |
| |
| class MEDIA_EXPORT AudioDecoder { |
| public: |
| // Status codes for decode operations. |
| // TODO(rileya): Now that both AudioDecoder and VideoDecoder Status enums |
| // match, break them into a decoder_status.h. |
| enum Status { |
| kOk, // We're all good. |
| kAborted, // We aborted as a result of Reset() or destruction. |
| kDecodeError, // A decoding error occurred. |
| kDecryptError // Decrypting error happened. |
| }; |
| |
| // Callback for AudioDecoder to return a decoded frame whenever it becomes |
| // available. Only non-EOS frames should be returned via this callback. |
| typedef base::Callback<void(const scoped_refptr<AudioBuffer>&)> OutputCB; |
| |
| // Callback for Decode(). Called after the decoder has completed decoding |
| // corresponding DecoderBuffer, indicating that it's ready to accept another |
| // buffer to decode. |
| typedef base::Callback<void(Status)> DecodeCB; |
| |
| AudioDecoder(); |
| |
| // Fires any pending callbacks, stops and destroys the decoder. |
| // Note: Since this is a destructor, |this| will be destroyed after this call. |
| // Make sure the callbacks fired from this call doesn't post any task that |
| // depends on |this|. |
| virtual ~AudioDecoder(); |
| |
| // Initializes an AudioDecoder with the given DemuxerStream, executing the |
| // callback upon completion. |
| // |statistics_cb| is used to update global pipeline statistics. |
| // |output_cb| is called for decoded audio buffers (see Decode()). |
| virtual void Initialize(const AudioDecoderConfig& config, |
| const PipelineStatusCB& status_cb, |
| const OutputCB& output_cb) = 0; |
| |
| // Requests samples to be decoded. Only one decode may be in flight at any |
| // given time. Once the buffer is decoded the decoder calls |decode_cb|. |
| // |output_cb| specified in Initialize() is called for each decoded buffer, |
| // before or after |decode_cb|. |
| // |
| // Implementations guarantee that the callbacks will not be called from within |
| // this method. |
| // |
| // If |buffer| is an EOS buffer then the decoder must be flushed, i.e. |
| // |output_cb| must be called for each frame pending in the queue and |
| // |decode_cb| must be called after that. |
| virtual void Decode(const scoped_refptr<DecoderBuffer>& buffer, |
| const DecodeCB& decode_cb) = 0; |
| |
| // Resets decoder state. All pending Decode() requests will be finished or |
| // aborted before |closure| is called. |
| virtual void Reset(const base::Closure& closure) = 0; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(AudioDecoder); |
| }; |
| |
| } // namespace media |
| |
| #endif // MEDIA_BASE_AUDIO_DECODER_H_ |