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Data Structures | Macros | Enumerations | Functions
timecode.h File Reference

Timecode helpers header. More...

#include <stdint.h>
#include "rational.h"

Go to the source code of this file.

Data Structures

struct  AVTimecode
 

Macros

#define AV_TIMECODE_STR_SIZE   23
 

Enumerations

enum  AVTimecodeFlag { AV_TIMECODE_FLAG_DROPFRAME = 1<<0, AV_TIMECODE_FLAG_24HOURSMAX = 1<<1, AV_TIMECODE_FLAG_ALLOWNEGATIVE = 1<<2 }
 

Functions

int av_timecode_adjust_ntsc_framenum2 (int framenum, int fps)
 Adjust frame number for NTSC drop frame time code. More...
 
uint32_t av_timecode_get_smpte_from_framenum (const AVTimecode *tc, int framenum)
 Convert frame number to SMPTE 12M binary representation. More...
 
char * av_timecode_make_string (const AVTimecode *tc, char *buf, int framenum)
 Load timecode string in buf. More...
 
char * av_timecode_make_smpte_tc_string (char *buf, uint32_t tcsmpte, int prevent_df)
 Get the timecode string from the SMPTE timecode format. More...
 
char * av_timecode_make_mpeg_tc_string (char *buf, uint32_t tc25bit)
 Get the timecode string from the 25-bit timecode format (MPEG GOP format). More...
 
int av_timecode_init (AVTimecode *tc, AVRational rate, int flags, int frame_start, void *log_ctx)
 Init a timecode struct with the passed parameters. More...
 
int av_timecode_init_from_string (AVTimecode *tc, AVRational rate, const char *str, void *log_ctx)
 Parse timecode representation (hh:mm:ss[:;. More...
 
int av_timecode_check_frame_rate (AVRational rate)
 Check if the timecode feature is available for the given frame rate. More...
 

Detailed Description

Timecode helpers header.

Definition in file timecode.h.

Macro Definition Documentation

#define AV_TIMECODE_STR_SIZE   23

Enumeration Type Documentation

Enumerator
AV_TIMECODE_FLAG_DROPFRAME 

timecode is drop frame

AV_TIMECODE_FLAG_24HOURSMAX 

timecode wraps after 24 hours

AV_TIMECODE_FLAG_ALLOWNEGATIVE 

negative time values are allowed

Definition at line 35 of file timecode.h.

Function Documentation

int av_timecode_adjust_ntsc_framenum2 ( int  framenum,
int  fps 
)

Adjust frame number for NTSC drop frame time code.

Parameters
framenumframe number to adjust
fpsframe per second, 30 or 60
Returns
adjusted frame number
Warning
adjustment is only valid in NTSC 29.97 and 59.94

Definition at line 34 of file timecode.c.

Referenced by av_timecode_get_smpte_from_framenum(), av_timecode_make_string(), and mpeg1_encode_sequence_header().

uint32_t av_timecode_get_smpte_from_framenum ( const AVTimecode tc,
int  framenum 
)

Convert frame number to SMPTE 12M binary representation.

Parameters
tctimecode data correctly initialized
framenumframe number
Returns
the SMPTE binary representation
Note
Frame number adjustment is automatically done in case of drop timecode, you do NOT have to call av_timecode_adjust_ntsc_framenum2().
The frame number is relative to tc->start.
Color frame (CF), binary group flags (BGF) and biphase mark polarity correction (PC) bits are set to zero.

Definition at line 55 of file timecode.c.

Referenced by dv_write_pack(), and mxf_write_system_item().

char* av_timecode_make_string ( const AVTimecode tc,
char *  buf,
int  framenum 
)

Load timecode string in buf.

Parameters
bufdestination buffer, must be at least AV_TIMECODE_STR_SIZE long
tctimecode data correctly initialized
framenumframe number
Returns
the buf parameter
Note
Timecode representation can be a negative timecode and have more than 24 hours, but will only be honored if the flags are correctly set.
The frame number is relative to tc->start.

Definition at line 84 of file timecode.c.

Referenced by draw_text(), mxf_add_timecode_metadata(), parse_timecode_in_framenum_format(), and segment_end().

char* av_timecode_make_smpte_tc_string ( char *  buf,
uint32_t  tcsmpte,
int  prevent_df 
)

Get the timecode string from the SMPTE timecode format.

Parameters
bufdestination buffer, must be at least AV_TIMECODE_STR_SIZE long
tcsmptethe 32-bit SMPTE timecode
prevent_dfprevent the use of a drop flag when it is known the DF bit is arbitrary
Returns
the buf parameter

Definition at line 118 of file timecode.c.

Referenced by dv_extract_timecode(), filter_frame(), show_frame(), and wsd_read_header().

char* av_timecode_make_mpeg_tc_string ( char *  buf,
uint32_t  tc25bit 
)

Get the timecode string from the 25-bit timecode format (MPEG GOP format).

Parameters
bufdestination buffer, must be at least AV_TIMECODE_STR_SIZE long
tc25bitthe 25-bits timecode
Returns
the buf parameter

Definition at line 130 of file timecode.c.

Referenced by mpeg_decode_gop(), show_frame(), and show_stream().

int av_timecode_init ( AVTimecode tc,
AVRational  rate,
int  flags,
int  frame_start,
void log_ctx 
)

Init a timecode struct with the passed parameters.

Parameters
log_ctxa pointer to an arbitrary struct of which the first field is a pointer to an AVClass struct (used for av_log)
tcpointer to an allocated AVTimecode
rateframe rate in rational form
flagsmiscellaneous flags such as drop frame, +24 hours, ... (see AVTimecodeFlag)
frame_startthe first frame number
Returns
0 on success, AVERROR otherwise

Definition at line 184 of file timecode.c.

Referenced by dv_write_header(), mxf_init_timecode(), mxf_parse_physical_source_package(), mxf_parse_structural_metadata(), and parse_timecode_in_framenum_format().

int av_timecode_init_from_string ( AVTimecode tc,
AVRational  rate,
const char *  str,
void log_ctx 
)

Parse timecode representation (hh:mm:ss[:;.

]ff).

Parameters
log_ctxa pointer to an arbitrary struct of which the first field is a pointer to an AVClass struct (used for av_log).
tcpointer to an allocated AVTimecode
rateframe rate in rational form
strtimecode string which will determine the frame start
Returns
0 on success, AVERROR otherwise

Definition at line 194 of file timecode.c.

Referenced by dv_write_header(), encode_init(), init(), mov_check_timecode_track(), mxf_init_timecode(), and segment_end().

int av_timecode_check_frame_rate ( AVRational  rate)

Check if the timecode feature is available for the given frame rate.

Returns
0 if supported, <0 otherwise

Definition at line 179 of file timecode.c.

Referenced by find_fps().