From b172c0f8c59c1d2921d6d1348ea2a5ae45b2288b Mon Sep 17 00:00:00 2001 From: Pierre-Anthony Lemieux Date: Fri, 11 Mar 2022 09:16:50 -0800 Subject: avformat/seek: add ff_rescale_interval() function Refactors a function used by avformat/concat and avformat/imf. Signed-off-by: Zane van Iperen --- libavformat/internal.h | 20 ++++++++++++++++++++ libavformat/seek.c | 10 ++++++++++ 2 files changed, 30 insertions(+) (limited to 'libavformat') diff --git a/libavformat/internal.h b/libavformat/internal.h index f24c68703f..342e6f7327 100644 --- a/libavformat/internal.h +++ b/libavformat/internal.h @@ -1023,4 +1023,24 @@ void avpriv_register_devices(const AVOutputFormat * const o[], const AVInputForm */ int ff_format_shift_data(AVFormatContext *s, int64_t read_start, int shift_size); +/** + * Rescales a timestamp and the endpoints of an interval to which the temstamp + * belongs, from a timebase `tb_in` to a timebase `tb_out`. + * + * The upper (lower) bound of the output interval is rounded up (down) such that + * the output interval always falls within the intput interval. The timestamp is + * rounded to the nearest integer and halfway cases away from zero, and can + * therefore fall outside of the output interval. + * + * Useful to simplify the rescaling of the arguments of AVInputFormat::read_seek2() + * + * @param[in] tb_in Timebase of the input `min_ts`, `ts` and `max_ts` + * @param[in] tb_out Timebase of the ouput `min_ts`, `ts` and `max_ts` + * @param[in,out] min_ts Lower bound of the interval + * @param[in,out] ts Timestamp + * @param[in,out] max_ts Upper bound of the interval + */ +void ff_rescale_interval(AVRational tb_in, AVRational tb_out, + int64_t *min_ts, int64_t *ts, int64_t *max_ts); + #endif /* AVFORMAT_INTERNAL_H */ diff --git a/libavformat/seek.c b/libavformat/seek.c index 405ca316b3..890aea7f8a 100644 --- a/libavformat/seek.c +++ b/libavformat/seek.c @@ -751,3 +751,13 @@ int avformat_flush(AVFormatContext *s) ff_read_frame_flush(s); return 0; } + +void ff_rescale_interval(AVRational tb_in, AVRational tb_out, + int64_t *min_ts, int64_t *ts, int64_t *max_ts) +{ + *ts = av_rescale_q (* ts, tb_in, tb_out); + *min_ts = av_rescale_q_rnd(*min_ts, tb_in, tb_out, + AV_ROUND_UP | AV_ROUND_PASS_MINMAX); + *max_ts = av_rescale_q_rnd(*max_ts, tb_in, tb_out, + AV_ROUND_DOWN | AV_ROUND_PASS_MINMAX); +} -- cgit v1.2.3