| // 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. |
| |
| #ifndef ACCELERATED_VIDEO_DECODER_H_ |
| #define ACCELERATED_VIDEO_DECODER_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include "base/macros.h" |
| #include "size.h" |
| |
| namespace media { |
| |
| // An AcceleratedVideoDecoder is a video decoder that requires support from an |
| // external accelerator (typically a hardware accelerator) to partially offload |
| // the decode process after parsing stream headers, and performing reference |
| // frame and state management. |
| class AcceleratedVideoDecoder { |
| public: |
| AcceleratedVideoDecoder() {} |
| virtual ~AcceleratedVideoDecoder() {} |
| |
| virtual void SetStream(const uint8_t* ptr, size_t size) = 0; |
| |
| // Have the decoder flush its state and trigger output of all previously |
| // decoded surfaces. Return false on failure. |
| virtual bool Flush() WARN_UNUSED_RESULT = 0; |
| |
| // Stop (pause) decoding, discarding all remaining inputs and outputs, |
| // but do not flush decoder state, so that playback can be resumed later, |
| // possibly from a different location. |
| // To be called during decoding. |
| virtual void Reset() = 0; |
| |
| enum DecodeResult { |
| kDecodeError, // Error while decoding. |
| // TODO(posciak): unsupported streams are currently treated as error |
| // in decoding; in future it could perhaps be possible to fall back |
| // to software decoding instead. |
| // kStreamError, // Error in stream. |
| kAllocateNewSurfaces, // Need a new set of surfaces to be allocated. |
| kRanOutOfStreamData, // Need more stream data to proceed. |
| kRanOutOfSurfaces, // Waiting for the client to free up output surfaces. |
| kNeedContextUpdate, // Waiting for the client to update decoding context |
| // with data acquired from the accelerator. |
| }; |
| |
| // Try to decode more of the stream, returning decoded frames asynchronously. |
| // Return when more stream is needed, when we run out of free surfaces, when |
| // we need a new set of them, or when an error occurs. |
| virtual DecodeResult Decode() WARN_UNUSED_RESULT = 0; |
| |
| // Return dimensions/required number of output surfaces that client should |
| // be ready to provide for the decoder to function properly. |
| // To be used after Decode() returns kAllocateNewSurfaces. |
| virtual Size GetPicSize() const = 0; |
| virtual size_t GetRequiredNumOfPictures() const = 0; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(AcceleratedVideoDecoder); |
| }; |
| |
| } // namespace media |
| |
| #endif // ACCELERATED_VIDEO_DECODER_H_ |