ref: 7d72ebaa5c43b8c55164cef38a321d9bc03f615a
dir: /vpx/vpx_decoder.h/
/*
* Copyright (c) 2010 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_DECODER_H_
#define VPX_VPX_DECODER_H_
/*!\defgroup decoder Decoder Algorithm Interface
* \ingroup codec
* This abstraction allows applications using this decoder to easily support
* multiple video formats with minimal code duplication. This section describes
* the interface common to all decoders.
* @{
*/
/*!\file
* \brief Describes the decoder algorithm interface to applications.
*
* This file describes the interface between an application and a
* video decoder algorithm.
*
*/
#ifdef __cplusplus
extern "C" {
#endif
#include "./vpx_codec.h"
#include "./vpx_frame_buffer.h"
/*!\brief Current ABI version number
*
* \internal
* If this file is altered in any way that changes the ABI, this value
* must be bumped. Examples include, but are not limited to, changing
* types, removing or reassigning enums, adding/removing/rearranging
* fields to structures
*/
#define VPX_DECODER_ABI_VERSION (3 + VPX_CODEC_ABI_VERSION) /**<\hideinitializer*/
/*! \brief Decoder capabilities bitfield
*
* Each decoder advertises the capabilities it supports as part of its
* ::vpx_codec_iface_t interface structure. Capabilities are extra interfaces
* or functionality, and are not required to be supported by a decoder.
*
* The available flags are specified by VPX_CODEC_CAP_* defines.
*/
#define VPX_CODEC_CAP_PUT_SLICE 0x10000 /**< Will issue put_slice callbacks */
#define VPX_CODEC_CAP_PUT_FRAME 0x20000 /**< Will issue put_frame callbacks */
#define VPX_CODEC_CAP_POSTPROC 0x40000 /**< Can postprocess decoded frame */
#define VPX_CODEC_CAP_ERROR_CONCEALMENT 0x80000 /**< Can conceal errors due to
packet loss */
#define VPX_CODEC_CAP_INPUT_FRAGMENTS 0x100000 /**< Can receive encoded frames
one fragment at a time */
/*! \brief Initialization-time Feature Enabling
*
* Certain codec features must be known at initialization time, to allow for
* proper memory allocation.
*
* The available flags are specified by VPX_CODEC_USE_* defines.
*/
#define VPX_CODEC_CAP_FRAME_THREADING 0x200000 /**< Can support frame-based
multi-threading */
#define VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER 0x400000 /**< Can support external
frame buffers */
#define VPX_CODEC_USE_POSTPROC 0x10000 /**< Postprocess decoded frame */
#define VPX_CODEC_USE_ERROR_CONCEALMENT 0x20000 /**< Conceal errors in decoded
frames */
#define VPX_CODEC_USE_INPUT_FRAGMENTS 0x40000 /**< The input frame should be
passed to the decoder one
fragment at a time */
#define VPX_CODEC_USE_FRAME_THREADING 0x80000 /**< Enable frame-based
multi-threading */
/*!\brief Stream properties
*
* This structure is used to query or set properties of the decoded
* stream. Algorithms may extend this structure with data specific
* to their bitstream by setting the sz member appropriately.
*/
typedef struct vpx_codec_stream_info {
unsigned int sz; /**< Size of this structure */
unsigned int w; /**< Width (or 0 for unknown/default) */
unsigned int h; /**< Height (or 0 for unknown/default) */
unsigned int is_kf; /**< Current frame is a keyframe */
} vpx_codec_stream_info_t;
/* REQUIRED FUNCTIONS
*
* The following functions are required to be implemented for all decoders.
* They represent the base case functionality expected of all decoders.
*/
/*!\brief Initialization Configurations
*
* This structure is used to pass init time configuration options to the
* decoder.
*/
typedef struct vpx_codec_dec_cfg {
unsigned int threads; /**< Maximum number of threads to use, default 1 */
unsigned int w; /**< Width */
unsigned int h; /**< Height */
} vpx_codec_dec_cfg_t; /**< alias for struct vpx_codec_dec_cfg */
/*!\brief Initialize a decoder instance
*
* Initializes a decoder context using the given interface. Applications
* should call the vpx_codec_dec_init convenience macro instead of this
* function directly, to ensure that the ABI version number parameter
* is properly initialized.
*
* If the library was configured with --disable-multithread, this call
* is not thread safe and should be guarded with a lock if being used
* in a multithreaded context.
*
* \param[in] ctx Pointer to this instance's context.
* \param[in] iface Pointer to the algorithm interface to use.
* \param[in] cfg Configuration to use, if known. May be NULL.
* \param[in] flags Bitfield of VPX_CODEC_USE_* flags
* \param[in] ver ABI version number. Must be set to
* VPX_DECODER_ABI_VERSION
* \retval #VPX_CODEC_OK
* The decoder algorithm initialized.
* \retval #VPX_CODEC_MEM_ERROR
* Memory allocation failed.
*/
vpx_codec_err_t vpx_codec_dec_init_ver(vpx_codec_ctx_t *ctx,
vpx_codec_iface_t *iface,
const vpx_codec_dec_cfg_t *cfg,
vpx_codec_flags_t flags,
int ver);
/*!\brief Convenience macro for vpx_codec_dec_init_ver()
*
* Ensures the ABI version parameter is properly set.
*/
#define vpx_codec_dec_init(ctx, iface, cfg, flags) \
vpx_codec_dec_init_ver(ctx, iface, cfg, flags, VPX_DECODER_ABI_VERSION)
/*!\brief Parse stream info from a buffer
*
* Performs high level parsing of the bitstream. Construction of a decoder
* context is not necessary. Can be used to determine if the bitstream is
* of the proper format, and to extract information from the stream.
*
* \param[in] iface Pointer to the algorithm interface
* \param[in] data Pointer to a block of data to parse
* \param[in] data_sz Size of the data buffer
* \param[in,out] si Pointer to stream info to update. The size member
* \ref MUST be properly initialized, but \ref MAY be
* clobbered by the algorithm. This parameter \ref MAY
* be NULL.
*
* \retval #VPX_CODEC_OK
* Bitstream is parsable and stream information updated
*/
vpx_codec_err_t vpx_codec_peek_stream_info(vpx_codec_iface_t *iface,
const uint8_t *data,
unsigned int data_sz,
vpx_codec_stream_info_t *si);
/*!\brief Return information about the current stream.
*
* Returns information about the stream that has been parsed during decoding.
*
* \param[in] ctx Pointer to this instance's context
* \param[in,out] si Pointer to stream info to update. The size member
* \ref MUST be properly initialized, but \ref MAY be
* clobbered by the algorithm. This parameter \ref MAY
* be NULL.
*
* \retval #VPX_CODEC_OK
* Bitstream is parsable and stream information updated
*/
vpx_codec_err_t vpx_codec_get_stream_info(vpx_codec_ctx_t *ctx,
vpx_codec_stream_info_t *si);
/*!\brief Decode data
*
* Processes a buffer of coded data. If the processing results in a new
* decoded frame becoming available, PUT_SLICE and PUT_FRAME events may be
* generated, as appropriate. Encoded data \ref MUST be passed in DTS (decode
* time stamp) order. Frames produced will always be in PTS (presentation
* time stamp) order.
* If the decoder is configured with VPX_CODEC_USE_INPUT_FRAGMENTS enabled,
* data and data_sz can contain a fragment of the encoded frame. Fragment
* \#n must contain at least partition \#n, but can also contain subsequent
* partitions (\#n+1 - \#n+i), and if so, fragments \#n+1, .., \#n+i must
* be empty. When no more data is available, this function should be called
* with NULL as data and 0 as data_sz. The memory passed to this function
* must be available until the frame has been decoded.
*
* \param[in] ctx Pointer to this instance's context
* \param[in] data Pointer to this block of new coded data. If
* NULL, a VPX_CODEC_CB_PUT_FRAME event is posted
* for the previously decoded frame.
* \param[in] data_sz Size of the coded data, in bytes.
* \param[in] user_priv Application specific data to associate with
* this frame.
* \param[in] deadline Soft deadline the decoder should attempt to meet,
* in us. Set to zero for unlimited.
*
* \return Returns #VPX_CODEC_OK if the coded data was processed completely
* and future pictures can be decoded without error. Otherwise,
* see the descriptions of the other error codes in ::vpx_codec_err_t
* for recoverability capabilities.
*/
vpx_codec_err_t vpx_codec_decode(vpx_codec_ctx_t *ctx,
const uint8_t *data,
unsigned int data_sz,
void *user_priv,
long deadline);
/*!\brief Decoded frames iterator
*
* Iterates over a list of the frames available for display. The iterator
* storage should be initialized to NULL to start the iteration. Iteration is
* complete when this function returns NULL.
*
* The list of available frames becomes valid upon completion of the
* vpx_codec_decode call, and remains valid until the next call to vpx_codec_decode.
*
* \param[in] ctx Pointer to this instance's context
* \param[in,out] iter Iterator storage, initialized to NULL
*
* \return Returns a pointer to an image, if one is ready for display. Frames
* produced will always be in PTS (presentation time stamp) order.
*/
vpx_image_t *vpx_codec_get_frame(vpx_codec_ctx_t *ctx,
vpx_codec_iter_t *iter);
/*!\defgroup cap_put_frame Frame-Based Decoding Functions
*
* The following functions are required to be implemented for all decoders
* that advertise the VPX_CODEC_CAP_PUT_FRAME capability. Calling these functions
* for codecs that don't advertise this capability will result in an error
* code being returned, usually VPX_CODEC_ERROR
* @{
*/
/*!\brief put frame callback prototype
*
* This callback is invoked by the decoder to notify the application of
* the availability of decoded image data.
*/
typedef void (*vpx_codec_put_frame_cb_fn_t)(void *user_priv,
const vpx_image_t *img);
/*!\brief Register for notification of frame completion.
*
* Registers a given function to be called when a decoded frame is
* available.
*
* \param[in] ctx Pointer to this instance's context
* \param[in] cb Pointer to the callback function
* \param[in] user_priv User's private data
*
* \retval #VPX_CODEC_OK
* Callback successfully registered.
* \retval #VPX_CODEC_ERROR
* Decoder context not initialized, or algorithm not capable of
* posting slice completion.
*/
vpx_codec_err_t vpx_codec_register_put_frame_cb(vpx_codec_ctx_t *ctx,
vpx_codec_put_frame_cb_fn_t cb,
void *user_priv);
/*!@} - end defgroup cap_put_frame */
/*!\defgroup cap_put_slice Slice-Based Decoding Functions
*
* The following functions are required to be implemented for all decoders
* that advertise the VPX_CODEC_CAP_PUT_SLICE capability. Calling these functions
* for codecs that don't advertise this capability will result in an error
* code being returned, usually VPX_CODEC_ERROR
* @{
*/
/*!\brief put slice callback prototype
*
* This callback is invoked by the decoder to notify the application of
* the availability of partially decoded image data. The
*/
typedef void (*vpx_codec_put_slice_cb_fn_t)(void *user_priv,
const vpx_image_t *img,
const vpx_image_rect_t *valid,
const vpx_image_rect_t *update);
/*!\brief Register for notification of slice completion.
*
* Registers a given function to be called when a decoded slice is
* available.
*
* \param[in] ctx Pointer to this instance's context
* \param[in] cb Pointer to the callback function
* \param[in] user_priv User's private data
*
* \retval #VPX_CODEC_OK
* Callback successfully registered.
* \retval #VPX_CODEC_ERROR
* Decoder context not initialized, or algorithm not capable of
* posting slice completion.
*/
vpx_codec_err_t vpx_codec_register_put_slice_cb(vpx_codec_ctx_t *ctx,
vpx_codec_put_slice_cb_fn_t cb,
void *user_priv);
/*!@} - end defgroup cap_put_slice*/
/*!\defgroup cap_external_frame_buffer External Frame Buffer Functions
*
* The following section is required to be implemented for all decoders
* that advertise the VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER capability.
* Calling this function for codecs that don't advertise this capability
* will result in an error code being returned, usually VPX_CODEC_ERROR.
*
* \note
* Currently this only works with VP9.
* @{
*/
/*!\brief Pass in external frame buffers for the decoder to use.
*
* Registers functions to be called when libvpx needs a frame buffer
* to decode the current frame and a function to be called when libvpx does
* not internally reference the frame buffer. This set function must
* be called before the first call to decode or libvpx will assume the
* default behavior of allocating frame buffers internally.
*
* \param[in] ctx Pointer to this instance's context
* \param[in] cb_get Pointer to the get callback function
* \param[in] cb_release Pointer to the release callback function
* \param[in] cb_priv Callback's private data
*
* \retval #VPX_CODEC_OK
* External frame buffers will be used by libvpx.
* \retval #VPX_CODEC_INVALID_PARAM
* One or more of the callbacks were NULL.
* \retval #VPX_CODEC_ERROR
* Decoder context not initialized, or algorithm not capable of
* using external frame buffers.
*
* \note
* When decoding VP9, the application may be required to pass in at least
* #VP9_MAXIMUM_REF_BUFFERS + #VPX_MAXIMUM_WORK_BUFFERS external frame
* buffers.
*/
vpx_codec_err_t vpx_codec_set_frame_buffer_functions(
vpx_codec_ctx_t *ctx,
vpx_get_frame_buffer_cb_fn_t cb_get,
vpx_release_frame_buffer_cb_fn_t cb_release, void *cb_priv);
/*!@} - end defgroup cap_external_frame_buffer */
/*!@} - end defgroup decoder*/
#ifdef __cplusplus
}
#endif
#endif // VPX_VPX_DECODER_H_