// 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_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
#define MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
#include <vector>
#include "base/basictypes.h"
#include "base/memory/weak_ptr.h"
#include "media/base/bitstream_buffer.h"
#include "media/base/video_decoder_config.h"
#include "media/video/picture.h"
#include "ui/gfx/size.h"
namespace media {
// Video decoder interface.
// This interface is extended by the various components that ultimately
// implement the backend of PPB_VideoDecode_Dev.
class MEDIA_EXPORT VideoDecodeAccelerator
: public base::SupportsWeakPtr<VideoDecodeAccelerator> {
public:
virtual ~VideoDecodeAccelerator();
// Enumeration of potential errors generated by the API.
// Note: Keep these in sync with PP_VideoDecodeError_Dev. Also do not
// rearrange, reuse or remove values as they are used for gathering UMA
// statistics.
enum Error {
// An operation was attempted during an incompatible decoder state.
ILLEGAL_STATE = 1,
// Invalid argument was passed to an API method.
INVALID_ARGUMENT,
// Encoded input is unreadable.
UNREADABLE_INPUT,
// A failure occurred at the browser layer or one of its dependencies.
// Examples of such failures include GPU hardware failures, GPU driver
// failures, GPU library failures, browser programming errors, and so on.
PLATFORM_FAILURE,
// Largest used enum. This should be adjusted when new errors are added.
LARGEST_ERROR_ENUM,
};
// Interface for collaborating with picture interface to provide memory for
// output picture and blitting them.
// This interface is extended by the various layers that relay messages back
// to the plugin, through the PPP_VideoDecode_Dev interface the plugin
// implements.
class MEDIA_EXPORT Client {
public:
// Callback to notify client that decoder has been initialized.
virtual void NotifyInitializeDone() = 0;
// Callback to tell client how many and what size of buffers to provide.
virtual void ProvidePictureBuffers(uint32 requested_num_of_buffers,
const gfx::Size& dimensions,
uint32 texture_target) = 0;
// Callback to dismiss picture buffer that was assigned earlier.
virtual void DismissPictureBuffer(int32 picture_buffer_id) = 0;
// Callback to deliver decoded pictures ready to be displayed.
virtual void PictureReady(const Picture& picture) = 0;
// Callback to notify that decoded has decoded the end of the current
// bitstream buffer.
virtual void NotifyEndOfBitstreamBuffer(int32 bitstream_buffer_id) = 0;
// Flush completion callback.
virtual void NotifyFlushDone() = 0;
// Reset completion callback.
virtual void NotifyResetDone() = 0;
// Callback to notify about decoding errors.
virtual void NotifyError(Error error) = 0;
protected:
virtual ~Client() {}
};
// Video decoder functions.
// Initializes the video decoder with specific configuration.
// Parameters:
// |profile| is the video stream's format profile.
//
// Returns true when command successfully accepted. Otherwise false.
virtual bool Initialize(VideoCodecProfile profile) = 0;
// Decodes given bitstream buffer that contains at most one frame. Once
// decoder is done with processing |bitstream_buffer| it will call
// NotifyEndOfBitstreamBuffer() with the bitstream buffer id.
// Parameters:
// |bitstream_buffer| is the input bitstream that is sent for decoding.
virtual void Decode(const BitstreamBuffer& bitstream_buffer) = 0;
// Assigns a set of texture-backed picture buffers to the video decoder.
//
// Ownership of each picture buffer remains with the client, but the client
// is not allowed to deallocate the buffer before the DismissPictureBuffer
// callback has been initiated for a given buffer.
//
// Parameters:
// |buffers| contains the allocated picture buffers for the output.
virtual void AssignPictureBuffers(
const std::vector<PictureBuffer>& buffers) = 0;
// Sends picture buffers to be reused by the decoder. This needs to be called
// for each buffer that has been processed so that decoder may know onto which
// picture buffers it can write the output to.
//
// Parameters:
// |picture_buffer_id| id of the picture buffer that is to be reused.
virtual void ReusePictureBuffer(int32 picture_buffer_id) = 0;
// Flushes the decoder: all pending inputs will be decoded and pictures handed
// back to the client, followed by NotifyFlushDone() being called on the
// client. Can be used to implement "end of stream" notification.
virtual void Flush() = 0;
// Resets the decoder: all pending inputs are dropped immediately and the
// decoder returned to a state ready for further Decode()s, followed by
// NotifyResetDone() being called on the client. Can be used to implement
// "seek".
virtual void Reset() = 0;
// Destroys the decoder: all pending inputs are dropped immediately and the
// component is freed. This call may asynchornously free system resources,
// but its client-visible effects are synchronous. After this method returns
// no more callbacks will be made on the client. Deletes |this|
// unconditionally, so make sure to drop all pointers to it!
virtual void Destroy() = 0;
};
} // namespace media
#endif // MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_