From 6df81ddb84c60876ac3ebd87d1d134109f34eabd Mon Sep 17 00:00:00 2001 From: Sebastian Parborg Date: Mon, 12 Jul 2021 19:13:15 +0200 Subject: VSE: Fix seeking issues. The seek pts was not correctly calculated. In addition to that we were not seeking in the video pts time base. Reviewed By: Richard Antalik Differential Revision: http://developer.blender.org/D11921 --- source/blender/imbuf/intern/anim_movie.c | 87 +++++++++++++++----------------- source/blender/imbuf/intern/indexer.c | 2 +- 2 files changed, 42 insertions(+), 47 deletions(-) (limited to 'source/blender/imbuf') diff --git a/source/blender/imbuf/intern/anim_movie.c b/source/blender/imbuf/intern/anim_movie.c index c08df2889de..fd96110b59e 100644 --- a/source/blender/imbuf/intern/anim_movie.c +++ b/source/blender/imbuf/intern/anim_movie.c @@ -1059,33 +1059,21 @@ static int ffmpeg_seek_by_byte(AVFormatContext *pFormatCtx) return false; } -static int64_t ffmpeg_get_seek_pos(struct anim *anim, int position) +static int64_t ffmpeg_get_seek_pts(struct anim *anim, int64_t pts_to_search) { AVStream *v_st = anim->pFormatCtx->streams[anim->videoStream]; - double frame_rate = av_q2d(av_guess_frame_rate(anim->pFormatCtx, v_st, NULL)); - int64_t st_time = anim->pFormatCtx->start_time; - int64_t pos = (int64_t)(position)*AV_TIME_BASE; - /* Step back half a time base position to make sure that we get the requested - * frame and not the one after it. + AVRational frame_rate = v_st->r_frame_rate; + AVRational time_base = v_st->time_base; + double steps_per_frame = (double)(frame_rate.den * time_base.den) / + (double)(frame_rate.num * time_base.num); + /* Step back half a frame position to make sure that we get the requested + * frame and not the one after it. This is a workaround as ffmpeg will + * sometimes not seek to a frame after the requested pts even if + * AVSEEK_FLAG_BACKWARD is specified. */ - pos -= (AV_TIME_BASE / 2); - pos /= frame_rate; + int64_t pts = pts_to_search - (steps_per_frame / 2); - av_log(anim->pFormatCtx, - AV_LOG_DEBUG, - "NO INDEX seek pos = %" PRId64 ", st_time = %" PRId64 "\n", - pos, - (st_time != AV_NOPTS_VALUE) ? st_time : 0); - - if (pos < 0) { - pos = 0; - } - - if (st_time != AV_NOPTS_VALUE) { - pos += st_time; - } - - return pos; + return pts; } /* This gives us an estimate of which pts our requested frame will have. @@ -1102,17 +1090,18 @@ static int64_t ffmpeg_get_pts_to_search(struct anim *anim, pts_to_search = IMB_indexer_get_pts(tc_index, new_frame_index); } else { - int64_t st_time = anim->pFormatCtx->start_time; AVStream *v_st = anim->pFormatCtx->streams[anim->videoStream]; - AVRational frame_rate = av_guess_frame_rate(anim->pFormatCtx, v_st, NULL); + int64_t start_pts = v_st->start_time; + AVRational frame_rate = v_st->r_frame_rate; AVRational time_base = v_st->time_base; - int64_t steps_per_frame = (frame_rate.den * time_base.den) / (frame_rate.num * time_base.num); - pts_to_search = position * steps_per_frame; + double steps_per_frame = (double)(frame_rate.den * time_base.den) / + (double)(frame_rate.num * time_base.num); + + pts_to_search = round(position * steps_per_frame); - if (st_time != AV_NOPTS_VALUE && st_time != 0) { - int64_t start_frame = (double)st_time / AV_TIME_BASE * av_q2d(frame_rate); - pts_to_search += start_frame * steps_per_frame; + if (start_pts != AV_NOPTS_VALUE) { + pts_to_search += start_pts; } } return pts_to_search; @@ -1196,23 +1185,29 @@ static void ffmpeg_decode_video_frame_scan(struct anim *anim, int64_t pts_to_sea * decoded will be read. See https://trac.ffmpeg.org/ticket/1607 and * https://developer.blender.org/T86944. */ static int ffmpeg_generic_seek_workaround(struct anim *anim, - int64_t *requested_pos, + int64_t *requested_pts, int64_t pts_to_search) { AVStream *v_st = anim->pFormatCtx->streams[anim->videoStream]; - double frame_rate = av_q2d(av_guess_frame_rate(anim->pFormatCtx, v_st, NULL)); - int64_t current_pos = *requested_pos; + AVRational frame_rate = v_st->r_frame_rate; + AVRational time_base = v_st->time_base; + + double steps_per_frame = (double)(frame_rate.den * time_base.den) / + (double)(frame_rate.num * time_base.num); + + int64_t current_pts = *requested_pts; int64_t offset = 0; int64_t cur_pts, prev_pts = -1; /* Step backward frame by frame until we find the key frame we are looking for. */ - while (current_pos != 0) { - current_pos = *requested_pos - ((int64_t)(offset)*AV_TIME_BASE / frame_rate); - current_pos = max_ii(current_pos, 0); + while (current_pts != 0) { + current_pts = *requested_pts - (int64_t)round(offset * steps_per_frame); + current_pts = max_ii(current_pts, 0); /* Seek to timestamp. */ - if (av_seek_frame(anim->pFormatCtx, -1, current_pos, AVSEEK_FLAG_BACKWARD) < 0) { + if (av_seek_frame(anim->pFormatCtx, anim->videoStream, current_pts, AVSEEK_FLAG_BACKWARD) < + 0) { break; } @@ -1249,10 +1244,10 @@ static int ffmpeg_generic_seek_workaround(struct anim *anim, offset++; } - *requested_pos = current_pos; + *requested_pts = current_pts; /* Re-seek to timestamp that gave I-frame, so it can be read by decode function. */ - return av_seek_frame(anim->pFormatCtx, -1, current_pos, AVSEEK_FLAG_BACKWARD); + return av_seek_frame(anim->pFormatCtx, anim->videoStream, current_pts, AVSEEK_FLAG_BACKWARD); } /* Seek to last necessary key frame. */ @@ -1300,13 +1295,13 @@ static int ffmpeg_seek_to_key_frame(struct anim *anim, else { /* We have to manually seek with ffmpeg to get to the key frame we want to start decoding from. */ - pos = ffmpeg_get_seek_pos(anim, position); + pos = ffmpeg_get_seek_pts(anim, pts_to_search); av_log(anim->pFormatCtx, AV_LOG_DEBUG, "NO INDEX final seek pos = %" PRId64 "\n", pos); AVFormatContext *format_ctx = anim->pFormatCtx; if (format_ctx->iformat->read_seek2 || format_ctx->iformat->read_seek) { - ret = av_seek_frame(anim->pFormatCtx, -1, pos, AVSEEK_FLAG_BACKWARD); + ret = av_seek_frame(anim->pFormatCtx, anim->videoStream, pos, AVSEEK_FLAG_BACKWARD); } else { ret = ffmpeg_generic_seek_workaround(anim, &pos, pts_to_search); @@ -1351,7 +1346,7 @@ static int ffmpeg_seek_to_key_frame(struct anim *anim, anim->cur_key_frame_pts = gop_pts; /* Seek back so we are at the correct position after we decoded a frame. */ - av_seek_frame(anim->pFormatCtx, -1, pos, AVSEEK_FLAG_BACKWARD); + av_seek_frame(anim->pFormatCtx, anim->videoStream, pos, AVSEEK_FLAG_BACKWARD); } } @@ -1391,18 +1386,18 @@ static ImBuf *ffmpeg_fetchibuf(struct anim *anim, int position, IMB_Timecode_Typ struct anim_index *tc_index = IMB_anim_open_index(anim, tc); int64_t pts_to_search = ffmpeg_get_pts_to_search(anim, tc_index, position); AVStream *v_st = anim->pFormatCtx->streams[anim->videoStream]; - double frame_rate = av_q2d(av_guess_frame_rate(anim->pFormatCtx, v_st, NULL)); + double frame_rate = av_q2d(v_st->r_frame_rate); double pts_time_base = av_q2d(v_st->time_base); - int64_t st_time = anim->pFormatCtx->start_time; + int64_t start_pts = v_st->start_time; av_log(anim->pFormatCtx, AV_LOG_DEBUG, - "FETCH: looking for PTS=%" PRId64 " (pts_timebase=%g, frame_rate=%g, st_time=%" PRId64 + "FETCH: looking for PTS=%" PRId64 " (pts_timebase=%g, frame_rate=%g, start_pts=%" PRId64 ")\n", (int64_t)pts_to_search, pts_time_base, frame_rate, - st_time); + start_pts); if (ffmpeg_pts_matches_last_frame(anim, pts_to_search)) { av_log(anim->pFormatCtx, diff --git a/source/blender/imbuf/intern/indexer.c b/source/blender/imbuf/intern/indexer.c index 27195b294d6..bbb0f3b5b22 100644 --- a/source/blender/imbuf/intern/indexer.c +++ b/source/blender/imbuf/intern/indexer.c @@ -1022,7 +1022,7 @@ static int index_rebuild_ffmpeg(FFmpegIndexBuilderContext *context, stream_size = avio_size(context->iFormatCtx->pb); - context->frame_rate = av_q2d(av_guess_frame_rate(context->iFormatCtx, context->iStream, NULL)); + context->frame_rate = av_q2d(context->iStream->r_frame_rate); context->pts_time_base = av_q2d(context->iStream->time_base); while (av_read_frame(context->iFormatCtx, next_packet) >= 0) { -- cgit v1.2.3