ref: a9c693aa8c57851291b0a0a0776ac6a32abf8b42
dir: /vpx/vpx_frame_buffer.h/
/*
* Copyright (c) 2014 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef VPX_VPX_VPX_FRAME_BUFFER_H_
#define VPX_VPX_VPX_FRAME_BUFFER_H_
/*!\file
* \brief Describes the decoder external frame buffer interface.
*/
#ifdef __cplusplus
extern "C" {
#endif
#include "./vpx_integer.h"
/*!\brief The maximum number of work buffers used by libvpx.
* Support maximum 4 threads to decode video in parallel.
* Each thread will use one work buffer.
* TODO(hkuang): Add support to set number of worker threads dynamically.
*/
#define VPX_MAXIMUM_WORK_BUFFERS 8
/*!\brief The maximum number of reference buffers that a VP9 encoder may use.
*/
#define VP9_MAXIMUM_REF_BUFFERS 8
/*!\brief External frame buffer
*
* This structure holds allocated frame buffers used by the decoder.
*/
typedef struct vpx_codec_frame_buffer {
uint8_t *data; /**< Pointer to the data buffer */
size_t size; /**< Size of data in bytes */
void *priv; /**< Frame's private data */
} vpx_codec_frame_buffer_t;
/*!\brief get frame buffer callback prototype
*
* This callback is invoked by the decoder to retrieve data for the frame
* buffer in order for the decode call to complete. The callback must
* allocate at least min_size in bytes and assign it to fb->data. The callback
* must zero out all the data allocated. Then the callback must set fb->size
* to the allocated size. The application does not need to align the allocated
* data. The callback is triggered when the decoder needs a frame buffer to
* decode a compressed image into. This function may be called more than once
* for every call to vpx_codec_decode. The application may set fb->priv to
* some data which will be passed back in the vpx_image_t and the release
* function call. |fb| is guaranteed to not be NULL. On success the callback
* must return 0. Any failure the callback must return a value less than 0.
*
* \param[in] priv Callback's private data
* \param[in] min_size Size in bytes needed by the buffer
* \param[in,out] fb Pointer to vpx_codec_frame_buffer_t
*/
typedef int (*vpx_get_frame_buffer_cb_fn_t)(void *priv, size_t min_size,
vpx_codec_frame_buffer_t *fb);
/*!\brief release frame buffer callback prototype
*
* This callback is invoked by the decoder when the frame buffer is not
* referenced by any other buffers. |fb| is guaranteed to not be NULL. On
* success the callback must return 0. Any failure the callback must return
* a value less than 0.
*
* \param[in] priv Callback's private data
* \param[in] fb Pointer to vpx_codec_frame_buffer_t
*/
typedef int (*vpx_release_frame_buffer_cb_fn_t)(void *priv,
vpx_codec_frame_buffer_t *fb);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // VPX_VPX_VPX_FRAME_BUFFER_H_