326 lines
11 KiB
C
326 lines
11 KiB
C
|
/*
|
||
|
|
* Bitstream filters public API
|
||
|
|
*
|
||
|
|
* This file is part of FFmpeg.
|
||
|
|
*
|
||
|
|
* FFmpeg is free software; you can redistribute it and/or
|
||
|
|
* modify it under the terms of the GNU Lesser General Public
|
||
|
|
* License as published by the Free Software Foundation; either
|
||
|
|
* version 2.1 of the License, or (at your option) any later version.
|
||
|
|
*
|
||
|
|
* FFmpeg is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
|
|
* Lesser General Public License for more details.
|
||
|
|
*
|
||
|
|
* You should have received a copy of the GNU Lesser General Public
|
||
|
|
* License along with FFmpeg; if not, write to the Free Software
|
||
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef AVCODEC_BSF_H
|
||
|
|
#define AVCODEC_BSF_H
|
||
|
|
|
||
|
|
#include "libavutil/dict.h"
|
||
|
|
#include "libavutil/log.h"
|
||
|
|
#include "libavutil/rational.h"
|
||
|
|
|
||
|
|
#include "codec_id.h"
|
||
|
|
#include "codec_par.h"
|
||
|
|
#include "packet.h"
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @addtogroup lavc_core
|
||
|
|
* @{
|
||
|
|
*/
|
||
|
|
|
||
|
|
typedef struct AVBSFInternal AVBSFInternal;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The bitstream filter state.
|
||
|
|
*
|
||
|
|
* This struct must be allocated with av_bsf_alloc() and freed with
|
||
|
|
* av_bsf_free().
|
||
|
|
*
|
||
|
|
* The fields in the struct will only be changed (by the caller or by the
|
||
|
|
* filter) as described in their documentation, and are to be considered
|
||
|
|
* immutable otherwise.
|
||
|
|
*/
|
||
|
|
typedef struct AVBSFContext {
|
||
|
|
/**
|
||
|
|
* A class for logging and AVOptions
|
||
|
|
*/
|
||
|
|
const AVClass *av_class;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The bitstream filter this context is an instance of.
|
||
|
|
*/
|
||
|
|
const struct AVBitStreamFilter *filter;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Opaque libavcodec internal data. Must not be touched by the caller in any
|
||
|
|
* way.
|
||
|
|
*/
|
||
|
|
AVBSFInternal *internal;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Opaque filter-specific private data. If filter->priv_class is non-NULL,
|
||
|
|
* this is an AVOptions-enabled struct.
|
||
|
|
*/
|
||
|
|
void *priv_data;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Parameters of the input stream. This field is allocated in
|
||
|
|
* av_bsf_alloc(), it needs to be filled by the caller before
|
||
|
|
* av_bsf_init().
|
||
|
|
*/
|
||
|
|
AVCodecParameters *par_in;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Parameters of the output stream. This field is allocated in
|
||
|
|
* av_bsf_alloc(), it is set by the filter in av_bsf_init().
|
||
|
|
*/
|
||
|
|
AVCodecParameters *par_out;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The timebase used for the timestamps of the input packets. Set by the
|
||
|
|
* caller before av_bsf_init().
|
||
|
|
*/
|
||
|
|
AVRational time_base_in;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The timebase used for the timestamps of the output packets. Set by the
|
||
|
|
* filter in av_bsf_init().
|
||
|
|
*/
|
||
|
|
AVRational time_base_out;
|
||
|
|
} AVBSFContext;
|
||
|
|
|
||
|
|
typedef struct AVBitStreamFilter {
|
||
|
|
const char *name;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A list of codec ids supported by the filter, terminated by
|
||
|
|
* AV_CODEC_ID_NONE.
|
||
|
|
* May be NULL, in that case the bitstream filter works with any codec id.
|
||
|
|
*/
|
||
|
|
const enum AVCodecID *codec_ids;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A class for the private data, used to declare bitstream filter private
|
||
|
|
* AVOptions. This field is NULL for bitstream filters that do not declare
|
||
|
|
* any options.
|
||
|
|
*
|
||
|
|
* If this field is non-NULL, the first member of the filter private data
|
||
|
|
* must be a pointer to AVClass, which will be set by libavcodec generic
|
||
|
|
* code to this class.
|
||
|
|
*/
|
||
|
|
const AVClass *priv_class;
|
||
|
|
|
||
|
|
/*****************************************************************
|
||
|
|
* No fields below this line are part of the public API. They
|
||
|
|
* may not be used outside of libavcodec and can be changed and
|
||
|
|
* removed at will.
|
||
|
|
* New public fields should be added right above.
|
||
|
|
*****************************************************************
|
||
|
|
*/
|
||
|
|
|
||
|
|
int priv_data_size;
|
||
|
|
int (*init)(AVBSFContext *ctx);
|
||
|
|
int (*filter)(AVBSFContext *ctx, AVPacket *pkt);
|
||
|
|
void (*close)(AVBSFContext *ctx);
|
||
|
|
void (*flush)(AVBSFContext *ctx);
|
||
|
|
} AVBitStreamFilter;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @return a bitstream filter with the specified name or NULL if no such
|
||
|
|
* bitstream filter exists.
|
||
|
|
*/
|
||
|
|
const AVBitStreamFilter *av_bsf_get_by_name(const char *name);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Iterate over all registered bitstream filters.
|
||
|
|
*
|
||
|
|
* @param opaque a pointer where libavcodec will store the iteration state. Must
|
||
|
|
* point to NULL to start the iteration.
|
||
|
|
*
|
||
|
|
* @return the next registered bitstream filter or NULL when the iteration is
|
||
|
|
* finished
|
||
|
|
*/
|
||
|
|
const AVBitStreamFilter *av_bsf_iterate(void **opaque);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Allocate a context for a given bitstream filter. The caller must fill in the
|
||
|
|
* context parameters as described in the documentation and then call
|
||
|
|
* av_bsf_init() before sending any data to the filter.
|
||
|
|
*
|
||
|
|
* @param filter the filter for which to allocate an instance.
|
||
|
|
* @param ctx a pointer into which the pointer to the newly-allocated context
|
||
|
|
* will be written. It must be freed with av_bsf_free() after the
|
||
|
|
* filtering is done.
|
||
|
|
*
|
||
|
|
* @return 0 on success, a negative AVERROR code on failure
|
||
|
|
*/
|
||
|
|
int av_bsf_alloc(const AVBitStreamFilter *filter, AVBSFContext **ctx);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Prepare the filter for use, after all the parameters and options have been
|
||
|
|
* set.
|
||
|
|
*/
|
||
|
|
int av_bsf_init(AVBSFContext *ctx);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Submit a packet for filtering.
|
||
|
|
*
|
||
|
|
* After sending each packet, the filter must be completely drained by calling
|
||
|
|
* av_bsf_receive_packet() repeatedly until it returns AVERROR(EAGAIN) or
|
||
|
|
* AVERROR_EOF.
|
||
|
|
*
|
||
|
|
* @param pkt the packet to filter. The bitstream filter will take ownership of
|
||
|
|
* the packet and reset the contents of pkt. pkt is not touched if an error occurs.
|
||
|
|
* If pkt is empty (i.e. NULL, or pkt->data is NULL and pkt->side_data_elems zero),
|
||
|
|
* it signals the end of the stream (i.e. no more non-empty packets will be sent;
|
||
|
|
* sending more empty packets does nothing) and will cause the filter to output
|
||
|
|
* any packets it may have buffered internally.
|
||
|
|
*
|
||
|
|
* @return 0 on success. AVERROR(EAGAIN) if packets need to be retrieved from the
|
||
|
|
* filter (using av_bsf_receive_packet()) before new input can be consumed. Another
|
||
|
|
* negative AVERROR value if an error occurs.
|
||
|
|
*/
|
||
|
|
int av_bsf_send_packet(AVBSFContext *ctx, AVPacket *pkt);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Retrieve a filtered packet.
|
||
|
|
*
|
||
|
|
* @param[out] pkt this struct will be filled with the contents of the filtered
|
||
|
|
* packet. It is owned by the caller and must be freed using
|
||
|
|
* av_packet_unref() when it is no longer needed.
|
||
|
|
* This parameter should be "clean" (i.e. freshly allocated
|
||
|
|
* with av_packet_alloc() or unreffed with av_packet_unref())
|
||
|
|
* when this function is called. If this function returns
|
||
|
|
* successfully, the contents of pkt will be completely
|
||
|
|
* overwritten by the returned data. On failure, pkt is not
|
||
|
|
* touched.
|
||
|
|
*
|
||
|
|
* @return 0 on success. AVERROR(EAGAIN) if more packets need to be sent to the
|
||
|
|
* filter (using av_bsf_send_packet()) to get more output. AVERROR_EOF if there
|
||
|
|
* will be no further output from the filter. Another negative AVERROR value if
|
||
|
|
* an error occurs.
|
||
|
|
*
|
||
|
|
* @note one input packet may result in several output packets, so after sending
|
||
|
|
* a packet with av_bsf_send_packet(), this function needs to be called
|
||
|
|
* repeatedly until it stops returning 0. It is also possible for a filter to
|
||
|
|
* output fewer packets than were sent to it, so this function may return
|
||
|
|
* AVERROR(EAGAIN) immediately after a successful av_bsf_send_packet() call.
|
||
|
|
*/
|
||
|
|
int av_bsf_receive_packet(AVBSFContext *ctx, AVPacket *pkt);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Reset the internal bitstream filter state / flush internal buffers.
|
||
|
|
*/
|
||
|
|
void av_bsf_flush(AVBSFContext *ctx);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Free a bitstream filter context and everything associated with it; write NULL
|
||
|
|
* into the supplied pointer.
|
||
|
|
*/
|
||
|
|
void av_bsf_free(AVBSFContext **ctx);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get the AVClass for AVBSFContext. It can be used in combination with
|
||
|
|
* AV_OPT_SEARCH_FAKE_OBJ for examining options.
|
||
|
|
*
|
||
|
|
* @see av_opt_find().
|
||
|
|
*/
|
||
|
|
const AVClass *av_bsf_get_class(void);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Structure for chain/list of bitstream filters.
|
||
|
|
* Empty list can be allocated by av_bsf_list_alloc().
|
||
|
|
*/
|
||
|
|
typedef struct AVBSFList AVBSFList;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Allocate empty list of bitstream filters.
|
||
|
|
* The list must be later freed by av_bsf_list_free()
|
||
|
|
* or finalized by av_bsf_list_finalize().
|
||
|
|
*
|
||
|
|
* @return Pointer to @ref AVBSFList on success, NULL in case of failure
|
||
|
|
*/
|
||
|
|
AVBSFList *av_bsf_list_alloc(void);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Free list of bitstream filters.
|
||
|
|
*
|
||
|
|
* @param lst Pointer to pointer returned by av_bsf_list_alloc()
|
||
|
|
*/
|
||
|
|
void av_bsf_list_free(AVBSFList **lst);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Append bitstream filter to the list of bitstream filters.
|
||
|
|
*
|
||
|
|
* @param lst List to append to
|
||
|
|
* @param bsf Filter context to be appended
|
||
|
|
*
|
||
|
|
* @return >=0 on success, negative AVERROR in case of failure
|
||
|
|
*/
|
||
|
|
int av_bsf_list_append(AVBSFList *lst, AVBSFContext *bsf);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Construct new bitstream filter context given it's name and options
|
||
|
|
* and append it to the list of bitstream filters.
|
||
|
|
*
|
||
|
|
* @param lst List to append to
|
||
|
|
* @param bsf_name Name of the bitstream filter
|
||
|
|
* @param options Options for the bitstream filter, can be set to NULL
|
||
|
|
*
|
||
|
|
* @return >=0 on success, negative AVERROR in case of failure
|
||
|
|
*/
|
||
|
|
int av_bsf_list_append2(AVBSFList *lst, const char * bsf_name, AVDictionary **options);
|
||
|
|
/**
|
||
|
|
* Finalize list of bitstream filters.
|
||
|
|
*
|
||
|
|
* This function will transform @ref AVBSFList to single @ref AVBSFContext,
|
||
|
|
* so the whole chain of bitstream filters can be treated as single filter
|
||
|
|
* freshly allocated by av_bsf_alloc().
|
||
|
|
* If the call is successful, @ref AVBSFList structure is freed and lst
|
||
|
|
* will be set to NULL. In case of failure, caller is responsible for
|
||
|
|
* freeing the structure by av_bsf_list_free()
|
||
|
|
*
|
||
|
|
* @param lst Filter list structure to be transformed
|
||
|
|
* @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
|
||
|
|
* representing the chain of bitstream filters
|
||
|
|
*
|
||
|
|
* @return >=0 on success, negative AVERROR in case of failure
|
||
|
|
*/
|
||
|
|
int av_bsf_list_finalize(AVBSFList **lst, AVBSFContext **bsf);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Parse string describing list of bitstream filters and create single
|
||
|
|
* @ref AVBSFContext describing the whole chain of bitstream filters.
|
||
|
|
* Resulting @ref AVBSFContext can be treated as any other @ref AVBSFContext freshly
|
||
|
|
* allocated by av_bsf_alloc().
|
||
|
|
*
|
||
|
|
* @param str String describing chain of bitstream filters in format
|
||
|
|
* `bsf1[=opt1=val1:opt2=val2][,bsf2]`
|
||
|
|
* @param[out] bsf Pointer to be set to newly created @ref AVBSFContext structure
|
||
|
|
* representing the chain of bitstream filters
|
||
|
|
*
|
||
|
|
* @return >=0 on success, negative AVERROR in case of failure
|
||
|
|
*/
|
||
|
|
int av_bsf_list_parse_str(const char *str, AVBSFContext **bsf);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get null/pass-through bitstream filter.
|
||
|
|
*
|
||
|
|
* @param[out] bsf Pointer to be set to new instance of pass-through bitstream filter
|
||
|
|
*
|
||
|
|
* @return
|
||
|
|
*/
|
||
|
|
int av_bsf_get_null_filter(AVBSFContext **bsf);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @}
|
||
|
|
*/
|
||
|
|
|
||
|
|
#endif // AVCODEC_BSF_H
|