blob: e2d5926163baaff11d9d84e2fca0ba63fad2261a [file] [log] [blame]
// 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.
#include <string>
#include "base/callback.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "media/base/audio_decoder_config.h"
#include "media/base/channel_layout.h"
#include "media/base/decode_status.h"
#include "media/base/decoder_buffer.h"
#include "media/base/media_export.h"
#include "media/base/pipeline_status.h"
#include "media/base/waiting.h"
namespace media {
class AudioBuffer;
class CdmContext;
class MEDIA_EXPORT AudioDecoder {
// Callback for VideoDecoder initialization.
using InitCB = base::Callback<void(bool success)>;
// Callback for AudioDecoder to return a decoded frame whenever it becomes
// available. Only non-EOS frames should be returned via this callback.
using OutputCB = base::Callback<void(const scoped_refptr<AudioBuffer>&)>;
// Callback for Decode(). Called after the decoder has accepted corresponding
// DecoderBuffer, indicating that the pipeline can send next buffer to decode.
using DecodeCB = base::Callback<void(DecodeStatus)>;
// 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();
// Returns the name of the decoder for logging and decoder selection purposes.
// This name should be available immediately after construction (e.g. before
// Initialize() is called). It should also be stable in the sense that the
// name does not change across multiple constructions.
// TODO(xhwang): Rename this method since the name is not only for display.
virtual std::string GetDisplayName() const = 0;
// Returns true if the implementation is expected to be implemented by the
// platform. The value should be available immediately after construction and
// should not change within the lifetime of a decoder instance. The value is
// used only for logging.
virtual bool IsPlatformDecoder() const;
// Initializes an AudioDecoder with |config|, executing the |init_cb| upon
// completion.
// |cdm_context| can be used to handle encrypted buffers. May be null if the
// stream is not encrypted.
// |init_cb| is used to return initialization status.
// |output_cb| is called for decoded audio buffers (see Decode()).
// |waiting_cb| is called whenever the decoder is stalled waiting for
// something, e.g. decryption key. May be called at any time after
// Initialize().
virtual void Initialize(const AudioDecoderConfig& config,
CdmContext* cdm_context,
const InitCB& init_cb,
const OutputCB& output_cb,
const WaitingCB& waiting_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(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;
// Returns true if the decoder needs bitstream conversion before decoding.
virtual bool NeedsBitstreamConversion() const;
} // namespace media