ffmpeg | branch: master | Niklas Haas <g...@haasn.dev> | Mon Jun 16 19:41:23 2025 +0200| [c0698840c41ced3f2fd0ff4070fd4294e6164dd6] | committer: Niklas Haas
avfilter/vf_libplacebo: correctly update SAR to reflect scaled result This aligns the behavior of vf_libplacebo with other filters in the vf_scale family, that forward any change in the SAR as a result of changing the output resolution to the output frame / link, and updates the ff_scale_adjust_dimensions() call to continue working as intended. The new behavior reflects the documentation of vf_libplacebo, which described this behavior despite that not being the way the filter worked up to this point. As an aside, also fixes a bug where the AVFrame SAR was inconsistent with the AVFilterLink SAR when the s->nb_inputs > 1 condition was met. > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c0698840c41ced3f2fd0ff4070fd4294e6164dd6 --- libavfilter/vf_libplacebo.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/libavfilter/vf_libplacebo.c b/libavfilter/vf_libplacebo.c index f14b0f9296..52731caa6c 100644 --- a/libavfilter/vf_libplacebo.c +++ b/libavfilter/vf_libplacebo.c @@ -186,6 +186,7 @@ typedef struct LibplaceboContext { float corner_rounding; int force_original_aspect_ratio; int force_divisible_by; + int reset_sar; int normalize_sar; int apply_filmgrain; int apply_dovi; @@ -929,6 +930,15 @@ static int output_frame(AVFilterContext *ctx, int64_t pts) if (s->apply_filmgrain) av_frame_remove_side_data(out, AV_FRAME_DATA_FILM_GRAIN_PARAMS); + if (s->reset_sar) { + out->sample_aspect_ratio = ref->sample_aspect_ratio; + } else { + const AVRational ar_ref = { ref->width, ref->height }; + const AVRational ar_out = { out->width, out->height }; + const AVRational stretch = av_div_q(ar_ref, ar_out); + out->sample_aspect_ratio = av_mul_q(ref->sample_aspect_ratio, stretch); + } + /* Map, render and unmap output frame */ if (outdesc->flags & AV_PIX_FMT_FLAG_HWACCEL) { ok = pl_map_avframe_ex(s->gpu, &target, pl_avframe_params( @@ -1288,19 +1298,28 @@ static int libplacebo_config_output(AVFilterLink *outlink) RET(ff_scale_eval_dimensions(s, s->w_expr, s->h_expr, inlink, outlink, &outlink->w, &outlink->h)); + s->reset_sar = s->normalize_sar || s->nb_inputs > 1; + double sar_in = inlink->sample_aspect_ratio.num ? + av_q2d(inlink->sample_aspect_ratio) : 1.0; + ff_scale_adjust_dimensions(inlink, &outlink->w, &outlink->h, s->force_original_aspect_ratio, - s->force_divisible_by, 1.f); + s->force_divisible_by, + s->reset_sar ? sar_in : 1.0); - if (s->normalize_sar || s->nb_inputs > 1) { + if (s->reset_sar) { /* SAR is normalized, or we have multiple inputs, set out to 1:1 */ outlink->sample_aspect_ratio = (AVRational){ 1, 1 }; - } else { + } else if (inlink->sample_aspect_ratio.num) { /* This is consistent with other scale_* filters, which only * set the outlink SAR to be equal to the scale SAR iff the input SAR * was set to something nonzero */ - if (inlink->sample_aspect_ratio.num) - outlink->sample_aspect_ratio = inlink->sample_aspect_ratio; + const AVRational ar_in = { inlink->w, inlink->h }; + const AVRational ar_out = { outlink->w, outlink->h }; + const AVRational stretch = av_div_q(ar_in, ar_out); + outlink->sample_aspect_ratio = av_mul_q(inlink->sample_aspect_ratio, stretch); + } else { + outlink->sample_aspect_ratio = inlink->sample_aspect_ratio; } /* Frame rate */ _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
