FFmpeg/av_timecode_init_from_string() with "59.94DF" support

str2tc.c

/*
 * https://github.com/intel/ffmpeg_libyami/blob/master/libavutil/timecode.c
 */
inline int av_timecode_init_from_string2(AVTimecode* tc, AVRational rate, const char* str)
{
#if 0
	return av_timecode_init_from_string(&tc, rate, str, NULL);
#else
	char c;
	int hh, mm, ss, ff;
	if (sscanf(str, "%d:%d:%d%c%d", &hh, &mm, &ss, &c, &ff) != 5)
		return AVERROR_INVALIDDATA;

	tc->flags = c != ':' ? AV_TIMECODE_FLAG_DROPFRAME : 0;
	tc->rate  = rate;
	tc->fps   = (rate.num + rate.den/2) / rate.den;
	tc->start = (hh*3600 + mm*60 + ss) * tc->fps + ff;
	if (tc->flags & AV_TIMECODE_FLAG_DROPFRAME) {
		int tmins = 60*hh + mm;
		int factor = (tc->fps == 30) ? 2 : 4;  // 30 or 60
		tc->start -= factor * (tmins - tmins/10);
	}
	return 0;
#endif
}