avutil/timecode: add function av_timecode_get_smpte()

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
This commit is contained in:
Limin Wang 2020-06-24 13:59:34 +08:00
parent 12c42c709e
commit 79723c2a87
2 changed files with 45 additions and 0 deletions

View File

@ -81,6 +81,38 @@ uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum)
(hh % 10); // units of hours
}
uint32_t av_timecode_get_smpte(AVRational rate, int drop, int hh, int mm, int ss, int ff)
{
uint32_t tc = 0;
uint32_t frames;
/* For SMPTE 12-M timecodes, frame count is a special case if > 30 FPS.
See SMPTE ST 12-1:2014 Sec 12.1 for more info. */
if (av_cmp_q(rate, (AVRational) {30, 1}) == 1) {
frames = ff / 2;
if (ff % 2 == 1) {
if (av_cmp_q(rate, (AVRational) {50, 1}) == 0)
tc |= (1 << 7);
else
tc |= (1 << 23);
}
} else {
frames = ff;
}
tc |= drop << 30;
tc |= (frames / 10) << 28;
tc |= (frames % 10) << 24;
tc |= (ss / 10) << 20;
tc |= (ss % 10) << 16;
tc |= (mm / 10) << 12;
tc |= (mm % 10) << 8;
tc |= (hh / 10) << 4;
tc |= (hh % 10);
return tc;
}
char *av_timecode_make_string(const AVTimecode *tc, char *buf, int framenum)
{
int fps = tc->fps;

View File

@ -70,6 +70,19 @@ int av_timecode_adjust_ntsc_framenum2(int framenum, int fps);
*/
uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum);
/**
* Convert sei info to SMPTE 12M binary representation.
*
* @param rate frame rate in rational form
* @param drop drop flag
* @param hh hour
* @param mm minute
* @param ss second
* @param ff frame number
* @return the SMPTE binary representation
*/
uint32_t av_timecode_get_smpte(AVRational rate, int drop, int hh, int mm, int ss, int ff);
/**
* Load timecode string in buf.
*