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Data Structures | Typedefs | Functions
cbs.h File Reference
#include <stddef.h>
#include <stdint.h>
#include "avcodec.h"

Go to the source code of this file.

Data Structures

struct  CodedBitstreamUnit
 Coded bitstream unit structure. More...
 
struct  CodedBitstreamFragment
 Coded bitstream fragment structure, combining one or more units. More...
 
struct  CodedBitstreamContext
 Context structure for coded bitstream operations. More...
 

Typedefs

typedef uint32_t CodedBitstreamUnitType
 The codec-specific type of a bitstream unit. More...
 

Functions

int ff_cbs_init (CodedBitstreamContext **ctx, enum AVCodecID codec_id, void *log_ctx)
 Create and initialise a new context for the given codec. More...
 
void ff_cbs_close (CodedBitstreamContext **ctx)
 Close a context and free all internal state. More...
 
int ff_cbs_read_extradata (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const AVCodecParameters *par)
 Read the extradata bitstream found in codec parameters into a fragment, then split into units and decompose. More...
 
int ff_cbs_read_packet (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const AVPacket *pkt)
 Read the data bitstream from a packet into a fragment, then split into units and decompose. More...
 
int ff_cbs_read (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const uint8_t *data, size_t size)
 Read a bitstream from a memory region into a fragment, then split into units and decompose. More...
 
int ff_cbs_write_fragment_data (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag)
 Write the content of the fragment to its own internal buffer. More...
 
int ff_cbs_write_extradata (CodedBitstreamContext *ctx, AVCodecParameters *par, CodedBitstreamFragment *frag)
 Write the bitstream of a fragment to the extradata in codec parameters. More...
 
int ff_cbs_write_packet (CodedBitstreamContext *ctx, AVPacket *pkt, CodedBitstreamFragment *frag)
 Write the bitstream of a fragment to a packet. More...
 
void ff_cbs_fragment_uninit (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag)
 Free all allocated memory in a fragment. More...
 
int ff_cbs_insert_unit_content (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, int position, CodedBitstreamUnitType type, void *content)
 Insert a new unit into a fragment with the given content. More...
 
int ff_cbs_insert_unit_data (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, int position, CodedBitstreamUnitType type, uint8_t *data, size_t data_size)
 Insert a new unit into a fragment with the given data bitstream. More...
 
int ff_cbs_delete_unit (CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, int position)
 Delete a unit from a fragment and free all memory it uses. More...
 

Typedef Documentation

typedef uint32_t CodedBitstreamUnitType

The codec-specific type of a bitstream unit.

H.264 / AVC: nal_unit_type H.265 / HEVC: nal_unit_type MPEG-2: start code value (without prefix)

Definition at line 41 of file cbs.h.

Function Documentation

int ff_cbs_init ( CodedBitstreamContext **  ctx,
enum AVCodecID  codec_id,
void log_ctx 
)
void ff_cbs_close ( CodedBitstreamContext **  ctx)
int ff_cbs_read_extradata ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag,
const AVCodecParameters par 
)

Read the extradata bitstream found in codec parameters into a fragment, then split into units and decompose.

This also updates the internal state, so will need to be called for codecs with extradata to read parameter sets necessary for further parsing even if the fragment itself is not desired.

Definition at line 151 of file cbs.c.

Referenced by h264_metadata_init(), h264_redundant_pps_init(), h265_metadata_init(), mpeg2_metadata_init(), and trace_headers_init().

int ff_cbs_read_packet ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag,
const AVPacket pkt 
)

Read the data bitstream from a packet into a fragment, then split into units and decompose.

This also updates the internal state of the coded bitstream context with any persistent data from the fragment which may be required to read following fragments (e.g. parameter sets).

Definition at line 172 of file cbs.c.

Referenced by h264_metadata_filter(), h264_redundant_pps_filter(), h265_metadata_filter(), mpeg2_metadata_filter(), and trace_headers().

int ff_cbs_read ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag,
const uint8_t data,
size_t  size 
)

Read a bitstream from a memory region into a fragment, then split into units and decompose.

This also updates the internal state of the coded bitstream context with any persistent data from the fragment which may be required to read following fragments (e.g. parameter sets).

Definition at line 193 of file cbs.c.

int ff_cbs_write_fragment_data ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag 
)

Write the content of the fragment to its own internal buffer.

Writes the content of all units and then assembles them into a new data buffer. When modifying the content of decomposed units, this can be used to regenerate the bitstream form of units or the whole fragment so that it can be extracted for other use.

This also updates the internal state of the coded bitstream context with any persistent data from the fragment which may be required to write following fragments (e.g. parameter sets).

Definition at line 216 of file cbs.c.

Referenced by ff_cbs_write_extradata(), ff_cbs_write_packet(), vaapi_encode_h264_write_access_unit(), vaapi_encode_h265_write_access_unit(), and vaapi_encode_mpeg2_write_fragment().

int ff_cbs_write_extradata ( CodedBitstreamContext ctx,
AVCodecParameters par,
CodedBitstreamFragment frag 
)

Write the bitstream of a fragment to the extradata in codec parameters.

This replaces any existing extradata in the structure.

Definition at line 242 of file cbs.c.

Referenced by h264_metadata_init(), h264_redundant_pps_init(), h265_metadata_init(), and mpeg2_metadata_init().

int ff_cbs_write_packet ( CodedBitstreamContext ctx,
AVPacket pkt,
CodedBitstreamFragment frag 
)

Write the bitstream of a fragment to a packet.

Definition at line 267 of file cbs.c.

Referenced by h264_metadata_filter(), h264_redundant_pps_filter(), h265_metadata_filter(), and mpeg2_metadata_filter().

void ff_cbs_fragment_uninit ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag 
)
int ff_cbs_insert_unit_content ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag,
int  position,
CodedBitstreamUnitType  type,
void content 
)

Insert a new unit into a fragment with the given content.

The content structure continues to be owned by the caller, and will not be freed when the unit is.

Definition at line 422 of file cbs.c.

Referenced by h264_metadata_filter(), h265_metadata_filter(), mpeg2_metadata_update_fragment(), vaapi_encode_h264_add_nal(), vaapi_encode_h265_add_nal(), and vaapi_encode_mpeg2_add_header().

int ff_cbs_insert_unit_data ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag,
int  position,
CodedBitstreamUnitType  type,
uint8_t data,
size_t  data_size 
)

Insert a new unit into a fragment with the given data bitstream.

The data buffer will be owned by the unit after this operation.

Definition at line 445 of file cbs.c.

Referenced by cbs_h2645_fragment_add_nals(), and cbs_mpeg2_split_fragment().

int ff_cbs_delete_unit ( CodedBitstreamContext ctx,
CodedBitstreamFragment frag,
int  position 
)

Delete a unit from a fragment and free all memory it uses.

Definition at line 468 of file cbs.c.

Referenced by h264_metadata_filter(), h264_redundant_pps_filter(), and h265_metadata_filter().