This value - while it looks like the actual range of the content - is nothing but the internal value of swscale.
Thus, if we have RGB content, translate the value to 1 which is what at least this filter expects for RGB. Swscale will ignore this value when set. Additionally, after calling sws_setColorspaceDetails double-check the configured internal flag for the color range. Warn if this is different to the requested value. Finally, utilize the translated configured output value as the output AVFrame's color_range. --- libavfilter/vf_scale.c | 44 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 43 insertions(+), 1 deletion(-) diff --git a/libavfilter/vf_scale.c b/libavfilter/vf_scale.c index 58eee96744..da8ce399cf 100644 --- a/libavfilter/vf_scale.c +++ b/libavfilter/vf_scale.c @@ -647,6 +647,8 @@ static int scale_slice(AVFilterLink *link, AVFrame *out_buf, AVFrame *cur_pic, s out,out_stride); } +// swscale's internal range flag is 0 for RGB, which we have to override +#define NORMALIZE_SWS_RANGE(format_flags, sws_range) (((format_flags) & AV_PIX_FMT_FLAG_RGB) ? 1 : (sws_range)) static int scale_frame(AVFilterLink *link, AVFrame *in, AVFrame **frame_out) { AVFilterContext *ctx = link->dst; @@ -750,11 +752,19 @@ scale: || in_range != AVCOL_RANGE_UNSPECIFIED || scale->out_range != AVCOL_RANGE_UNSPECIFIED) { int in_full, out_full, brightness, contrast, saturation; + int configured_in_full_range_flag, configured_out_full_range_flag; const int *inv_table, *table; + const AVPixFmtDescriptor *in_desc = av_pix_fmt_desc_get(in->format); + const AVPixFmtDescriptor *out_desc = av_pix_fmt_desc_get(out->format); + av_assert0(in_desc && out_desc); sws_getColorspaceDetails(scale->sws, (int **)&inv_table, &in_full, (int **)&table, &out_full, &brightness, &contrast, &saturation); + // translate the internal range flags according to this + // filter's expectations for RGB. + in_full = NORMALIZE_SWS_RANGE(in_desc->flags, in_full); + out_full = NORMALIZE_SWS_RANGE(out_desc->flags, out_full); if (scale->in_color_matrix) inv_table = parse_yuv_type(scale->in_color_matrix, in->colorspace); @@ -782,7 +792,39 @@ scale: table, out_full, brightness, contrast, saturation); - out->color_range = out_full ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG; + // double-check what was actually just configured, + // since swscale can silently ignore the color range + // value in sws_setColorspaceDetails. + sws_getColorspaceDetails(scale->sws, (int **)&inv_table, + &configured_in_full_range_flag, + (int **)&table, + &configured_out_full_range_flag, + &brightness, &contrast, &saturation); + + // translate the actually configured internal range flags according + // to this filter's expectations for RGB. + configured_in_full_range_flag = \ + NORMALIZE_SWS_RANGE(in_desc->flags, + configured_in_full_range_flag); + configured_out_full_range_flag = \ + NORMALIZE_SWS_RANGE(out_desc->flags, + configured_out_full_range_flag); + + if (in_full != configured_in_full_range_flag || + out_full != configured_out_full_range_flag) { + av_log(ctx, AV_LOG_WARNING, + "swscale overrode set input/output range value as it " + "considered it an invalid configuration! " + "(input: requested: %s, configured: %s), " + "(output: requested: %s, configured: %s)!\n", + in_full ? "full" : "limited", + configured_in_full_range_flag ? "full" : "limited", + out_full ? "full" : "limited", + configured_out_full_range_flag ? "full" : "limited"); + } + + out->color_range = configured_out_full_range_flag ? + AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG; } av_reduce(&out->sample_aspect_ratio.num, &out->sample_aspect_ratio.den, -- 2.26.2 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".