FFmpeg
Macros | Functions
mux.c File Reference

muxing functions for use within libavformat More...

#include "avformat.h"
#include "internal.h"
#include "libavcodec/internal.h"
#include "libavutil/opt.h"
#include "libavutil/dict.h"
#include "libavutil/pixdesc.h"
#include "libavutil/timestamp.h"
#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavutil/internal.h"
#include "libavutil/mathematics.h"

Go to the source code of this file.

Macros

#define AV_PKT_FLAG_UNCODED_FRAME   0x2000
 
#define CHUNK_START   0x1000
 

Functions

static void frac_init (FFFrac *f, int64_t val, int64_t num, int64_t den)
 f = val + (num / den) + 0.5. More...
 
static void frac_add (FFFrac *f, int64_t incr)
 Fractional addition to f: f = f + (incr / f->den). More...
 
AVRational ff_choose_timebase (AVFormatContext *s, AVStream *st, int min_precision)
 Chooses a timebase for muxing the specified stream. More...
 
enum AVChromaLocation ff_choose_chroma_location (AVFormatContext *s, AVStream *st)
 Chooses a timebase for muxing the specified stream. More...
 
int avformat_alloc_output_context2 (AVFormatContext **avctx, ff_const59 AVOutputFormat *oformat, const char *format, const char *filename)
 Allocate an AVFormatContext for an output format. More...
 
static int validate_codec_tag (AVFormatContext *s, AVStream *st)
 
static int init_muxer (AVFormatContext *s, AVDictionary **options)
 
static int init_pts (AVFormatContext *s)
 
static void flush_if_needed (AVFormatContext *s)
 
static void deinit_muxer (AVFormatContext *s)
 
int avformat_init_output (AVFormatContext *s, AVDictionary **options)
 Allocate the stream private data and initialize the codec, but do not write the header. More...
 
int avformat_write_header (AVFormatContext *s, AVDictionary **options)
 Allocate the stream private data and write the stream header to an output media file. More...
 
static int write_packet (AVFormatContext *s, AVPacket *pkt)
 Shift timestamps and call muxer; the original pts/dts are not kept. More...
 
static int check_packet (AVFormatContext *s, AVPacket *pkt)
 
static int prepare_input_packet (AVFormatContext *s, AVStream *st, AVPacket *pkt)
 
int ff_interleave_add_packet (AVFormatContext *s, AVPacket *pkt, int(*compare)(AVFormatContext *, const AVPacket *, const AVPacket *))
 Add packet to an AVFormatContext's packet_buffer list, determining its interleaved position using compare() function argument. More...
 
static int interleave_compare_dts (AVFormatContext *s, const AVPacket *next, const AVPacket *pkt)
 
int ff_interleave_packet_per_dts (AVFormatContext *s, AVPacket *out, AVPacket *pkt, int flush)
 Interleave an AVPacket per dts so it can be muxed. More...
 
int ff_interleaved_peek (AVFormatContext *s, int stream, AVPacket *pkt, int add_offset)
 Find the next packet in the interleaving queue for the given stream. More...
 
static int interleave_packet (AVFormatContext *s, AVPacket *out, AVPacket *in, int flush)
 Interleave an AVPacket correctly so it can be muxed. More...
 
static int check_bitstream (AVFormatContext *s, AVStream *st, AVPacket *pkt)
 
static int interleaved_write_packet (AVFormatContext *s, AVPacket *pkt, int flush)
 
static int write_packet_common (AVFormatContext *s, AVStream *st, AVPacket *pkt, int interleaved)
 
static int write_packets_from_bsfs (AVFormatContext *s, AVStream *st, AVPacket *pkt, int interleaved)
 
static int write_packets_common (AVFormatContext *s, AVPacket *pkt, int interleaved)
 
int av_write_frame (AVFormatContext *s, AVPacket *in)
 Write a packet to an output media file. More...
 
int av_interleaved_write_frame (AVFormatContext *s, AVPacket *pkt)
 Write a packet to an output media file ensuring correct interleaving. More...
 
int av_write_trailer (AVFormatContext *s)
 Write the stream trailer to an output media file and free the file private data. More...
 
int av_get_output_timestamp (struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall)
 Get timing information for the data currently output. More...
 
int ff_write_chained (AVFormatContext *dst, int dst_stream, AVPacket *pkt, AVFormatContext *src, int interleave)
 Write a packet to another muxer than the one the user originally intended. More...
 
static void uncoded_frame_free (void *unused, uint8_t *data)
 
static int write_uncoded_frame_internal (AVFormatContext *s, int stream_index, AVFrame *frame, int interleaved)
 
int av_write_uncoded_frame (AVFormatContext *s, int stream_index, AVFrame *frame)
 Write an uncoded frame to an output media file. More...
 
int av_interleaved_write_uncoded_frame (AVFormatContext *s, int stream_index, AVFrame *frame)
 Write an uncoded frame to an output media file. More...
 
int av_write_uncoded_frame_query (AVFormatContext *s, int stream_index)
 Test whether a muxer supports uncoded frame. More...
 

Detailed Description

muxing functions for use within libavformat

Definition in file mux.c.

Macro Definition Documentation

#define AV_PKT_FLAG_UNCODED_FRAME   0x2000

Definition at line 540 of file mux.c.

Referenced by av_write_frame(), write_packet(), and write_uncoded_frame_internal().

#define CHUNK_START   0x1000

Definition at line 810 of file mux.c.

Referenced by ff_interleave_add_packet().

Function Documentation

static void frac_init ( FFFrac f,
int64_t  val,
int64_t  num,
int64_t  den 
)
static

f = val + (num / den) + 0.5.

'num' is normalized so that it is such as 0 <= num < den.

Parameters
ffractional number
valinteger value
nummust be >= 0
denmust be >= 1

Definition at line 51 of file mux.c.

Referenced by init_pts().

static void frac_add ( FFFrac f,
int64_t  incr 
)
static

Fractional addition to f: f = f + (incr / f->den).

Parameters
ffractional number
incrincrement, can be positive or negative

Definition at line 69 of file mux.c.

AVRational ff_choose_timebase ( AVFormatContext s,
AVStream st,
int  min_precision 
)

Chooses a timebase for muxing the specified stream.

The chosen timebase allows sample accurate timestamps based on the framerate or sample rate for audio streams. It also is at least as precise as 1/min_precision would be.

Definition at line 89 of file mux.c.

Referenced by nut_write_header().

enum AVChromaLocation ff_choose_chroma_location ( AVFormatContext s,
AVStream st 
)

Chooses a timebase for muxing the specified stream.

Definition at line 105 of file mux.c.

Referenced by mxf_write_header().

int avformat_alloc_output_context2 ( AVFormatContext **  ctx,
ff_const59 AVOutputFormat oformat,
const char *  format_name,
const char *  filename 
)

Allocate an AVFormatContext for an output format.

avformat_free_context() can be used to free the context and everything allocated by the framework within it.

Parameters
*ctxis set to the created format context, or to NULL in case of failure
oformatformat to use for allocating the context, if NULL format_name and filename are used instead
format_namethe name of output format to use for allocating the context, if NULL filename is used instead
filenamethe name of the filename to use for allocating the context, may be NULL
Returns
>= 0 in case of success, a negative AVERROR code in case of failure

Definition at line 135 of file mux.c.

Referenced by avdevice_list_output_sinks(), fifo_mux_init(), hls_mux_init(), initialize_fifo_tst_muxer_chain(), main(), open_output_file(), open_slave(), segment_mux_init(), webm_chunk_init(), and write_muxed_file().

static int validate_codec_tag ( AVFormatContext s,
AVStream st 
)
static

Check that tag + id is in the table If neither is in the table -> OK If tag is in the table with another id -> FAIL If id is in the table with another tag -> FAIL unless strict < normal

Definition at line 196 of file mux.c.

Referenced by init_muxer().

static int init_muxer ( AVFormatContext s,
AVDictionary **  options 
)
static

Definition at line 230 of file mux.c.

Referenced by avformat_init_output().

static int init_pts ( AVFormatContext s)
static

Definition at line 422 of file mux.c.

Referenced by avformat_init_output(), and avformat_write_header().

static void flush_if_needed ( AVFormatContext s)
static

Definition at line 467 of file mux.c.

Referenced by av_write_frame(), avformat_write_header(), and write_packet().

static void deinit_muxer ( AVFormatContext s)
static

Definition at line 477 of file mux.c.

Referenced by av_write_trailer(), and avformat_write_header().

static int write_packet ( AVFormatContext s,
AVPacket pkt 
)
static

Shift timestamps and call muxer; the original pts/dts are not kept.

FIXME: this function should NEVER get undefined pts/dts beside when the AVFMT_NOTIMESTAMPS is set. Those additional safety checks should be dropped once the correct checks are set in the callers.

Definition at line 663 of file mux.c.

Referenced by interleaved_write_packet(), and write_packet_common().

static int check_packet ( AVFormatContext s,
AVPacket pkt 
)
static

Definition at line 746 of file mux.c.

Referenced by write_packets_common().

static int prepare_input_packet ( AVFormatContext s,
AVStream st,
AVPacket pkt 
)
static

Definition at line 762 of file mux.c.

Referenced by write_packets_common().

int ff_interleave_add_packet ( AVFormatContext s,
AVPacket pkt,
int(*)(AVFormatContext *, const AVPacket *, const AVPacket *)  compare 
)

Add packet to an AVFormatContext's packet_buffer list, determining its interleaved position using compare() function argument.

Returns
0 on success, < 0 on error. pkt will always be blank on return.

Definition at line 812 of file mux.c.

Referenced by ff_interleave_packet_per_dts(), gxf_interleave_packet(), and mxf_interleave().

static int interleave_compare_dts ( AVFormatContext s,
const AVPacket next,
const AVPacket pkt 
)
static

Definition at line 884 of file mux.c.

Referenced by ff_interleave_packet_per_dts().

int ff_interleave_packet_per_dts ( AVFormatContext s,
AVPacket out,
AVPacket pkt,
int  flush 
)

Interleave an AVPacket per dts so it can be muxed.

Parameters
san AVFormatContext for output. pkt resp. out will be added to resp. taken from its packet buffer.
outthe interleaved packet will be output here
pktthe input packet; will be blank on return if not NULL
flush1 if no further packets are available as input and all remaining packets should be output
Returns
1 if a packet was output, 0 if no packet could be output (in which case out may be uninitialized), < 0 if an error occurred

Definition at line 914 of file mux.c.

Referenced by gxf_interleave_packet(), and interleave_packet().

int ff_interleaved_peek ( AVFormatContext s,
int  stream,
AVPacket pkt,
int  add_offset 
)

Find the next packet in the interleaving queue for the given stream.

The pkt parameter is filled in with the queued packet, including references to the data (which the caller is not allowed to keep or modify).

Returns
0 if a packet was found, a negative value if no packet was found

Definition at line 1032 of file mux.c.

Referenced by mov_flush_fragment().

static int interleave_packet ( AVFormatContext s,
AVPacket out,
AVPacket in,
int  flush 
)
static

Interleave an AVPacket correctly so it can be muxed.

Parameters
outthe interleaved packet will be output here
inthe input packet; will always be blank on return if not NULL
flush1 if no further packets are available as input and all remaining packets should be output
Returns
1 if a packet was output, 0 if no packet could be output, < 0 if an error occurred

Definition at line 1067 of file mux.c.

Referenced by interleaved_write_packet().

static int check_bitstream ( AVFormatContext s,
AVStream st,
AVPacket pkt 
)
static

Definition at line 1075 of file mux.c.

Referenced by write_packets_common().

static int interleaved_write_packet ( AVFormatContext s,
AVPacket pkt,
int  flush 
)
static

Definition at line 1094 of file mux.c.

Referenced by av_interleaved_write_frame(), av_write_trailer(), and write_packet_common().

static int write_packet_common ( AVFormatContext s,
AVStream st,
AVPacket pkt,
int  interleaved 
)
static

Definition at line 1113 of file mux.c.

Referenced by write_packets_common(), and write_packets_from_bsfs().

static int write_packets_from_bsfs ( AVFormatContext s,
AVStream st,
AVPacket pkt,
int  interleaved 
)
static

Definition at line 1135 of file mux.c.

Referenced by av_write_trailer(), and write_packets_common().

static int write_packets_common ( AVFormatContext s,
AVPacket pkt,
int  interleaved 
)
static

Definition at line 1167 of file mux.c.

Referenced by av_interleaved_write_frame(), and av_write_frame().

int ff_write_chained ( AVFormatContext dst,
int  dst_stream,
AVPacket pkt,
AVFormatContext src,
int  interleave 
)

Write a packet to another muxer than the one the user originally intended.

Useful when chaining muxers, where one muxer internally writes a received packet to another muxer.

Parameters
dstthe muxer to write the packet to
dst_streamthe stream index within dst to write the packet to
pktthe packet to be written
srcthe muxer the packet originally was intended for
interleave0->use av_write_frame, 1->av_interleaved_write_frame
Returns
the value av_write_frame returned

Definition at line 1305 of file mux.c.

Referenced by dash_write_packet(), ff_mov_add_hinted_packet(), hds_write_packet(), hls_write_packet(), ism_write_packet(), rtsp_write_packet(), sap_write_packet(), and seg_write_packet().

static void uncoded_frame_free ( void unused,
uint8_t data 
)
static

Definition at line 1326 of file mux.c.

Referenced by write_uncoded_frame_internal().

static int write_uncoded_frame_internal ( AVFormatContext s,
int  stream_index,
AVFrame frame,
int  interleaved 
)
static

Definition at line 1332 of file mux.c.

Referenced by av_interleaved_write_uncoded_frame(), and av_write_uncoded_frame().