Re: [FFmpeg-devel] [PATCH] lavc/x265: set preferred_transfer_characteristics for HLG
James Almer 于2019年12月13日周五 上午12:14写道： > > On 12/4/2019 11:24 AM, Zhong Li wrote: > > "HEVC HDR UHDTV Bitstreams using HLG10 shall also contain the > > alternative_transfer_characteristics SEI message. The > > alternative_transfer_characteristics SEI message shall be inserted on > > the HEVC DVB_RAP, and preferred_transfer_characteristics shall be set > > equal to "18", indicating Recommendation ITU-R BT. 2100 [45] HLG > > system." > > > > Signed-off-by: Zhong Li > > --- > > libavcodec/libx265.c | 4 > > 1 file changed, 4 insertions(+) > > > > diff --git a/libavcodec/libx265.c b/libavcodec/libx265.c > > index 4e75077..963c28f 100644 > > --- a/libavcodec/libx265.c > > +++ b/libavcodec/libx265.c > > @@ -159,6 +159,10 @@ static av_cold int libx265_encode_init(AVCodecContext > > *avctx) > > // x265 validates the parameters internally > > ctx->params->vui.colorPrimaries = avctx->color_primaries; > > ctx->params->vui.transferCharacteristics = avctx->color_trc; > > +#if X265_BUILD >= 159 > > +if (avctx->color_trc == AVCOL_TRC_ARIB_STD_B67) > > +ctx->params->preferredTransferCharacteristics = > > ctx->params->vui.transferCharacteristics; > > +#endif > > isn't the point of preferred_transfer_characteristics to have the Arib > value at the same time the standard VUI trc field contains a value like > BT2020 instead, for device backwards compat purposes? > > If both have the Arib value, then it seems redundant. It is also for robustness，if preferred_transfer_characteristics is existed but not set, decoder may use preferred_transfer_characteristics instead of vui transfer_characteristics. ___ 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".
Re: [FFmpeg-devel] [PATCH] lavc/x265: set preferred_transfer_characteristics for HLG
On Thu, Dec 12, 2019 at 11:14 AM James Almer wrote: > On 12/4/2019 11:24 AM, Zhong Li wrote: > > "HEVC HDR UHDTV Bitstreams using HLG10 shall also contain the > > alternative_transfer_characteristics SEI message. The > > alternative_transfer_characteristics SEI message shall be inserted on > > the HEVC DVB_RAP, and preferred_transfer_characteristics shall be set > > equal to "18", indicating Recommendation ITU-R BT. 2100 [45] HLG > > system." > > > > Signed-off-by: Zhong Li > > --- > > libavcodec/libx265.c | 4 > > 1 file changed, 4 insertions(+) > > > > diff --git a/libavcodec/libx265.c b/libavcodec/libx265.c > > index 4e75077..963c28f 100644 > > --- a/libavcodec/libx265.c > > +++ b/libavcodec/libx265.c > > @@ -159,6 +159,10 @@ static av_cold int > libx265_encode_init(AVCodecContext *avctx) > > // x265 validates the parameters internally > > ctx->params->vui.colorPrimaries = > avctx->color_primaries; > > ctx->params->vui.transferCharacteristics = avctx->color_trc; > > +#if X265_BUILD >= 159 > > +if (avctx->color_trc == AVCOL_TRC_ARIB_STD_B67) > > +ctx->params->preferredTransferCharacteristics = > ctx->params->vui.transferCharacteristics; > > +#endif > > isn't the point of preferred_transfer_characteristics to have the Arib > value at the same time the standard VUI trc field contains a value like > BT2020 instead, for device backwards compat purposes? > > If both have the Arib value, then it seems redundant. > yes but that is a new requirement from the dvb spec to my understanding i believe it is to encourage implementors to support this particular SEI -- Vittorio ___ 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".
Re: [FFmpeg-devel] [PATCH] lavc/x265: set preferred_transfer_characteristics for HLG
On 12/4/2019 11:24 AM, Zhong Li wrote: > "HEVC HDR UHDTV Bitstreams using HLG10 shall also contain the > alternative_transfer_characteristics SEI message. The > alternative_transfer_characteristics SEI message shall be inserted on > the HEVC DVB_RAP, and preferred_transfer_characteristics shall be set > equal to "18", indicating Recommendation ITU-R BT. 2100 [45] HLG > system." > > Signed-off-by: Zhong Li > --- > libavcodec/libx265.c | 4 > 1 file changed, 4 insertions(+) > > diff --git a/libavcodec/libx265.c b/libavcodec/libx265.c > index 4e75077..963c28f 100644 > --- a/libavcodec/libx265.c > +++ b/libavcodec/libx265.c > @@ -159,6 +159,10 @@ static av_cold int libx265_encode_init(AVCodecContext > *avctx) > // x265 validates the parameters internally > ctx->params->vui.colorPrimaries = avctx->color_primaries; > ctx->params->vui.transferCharacteristics = avctx->color_trc; > +#if X265_BUILD >= 159 > +if (avctx->color_trc == AVCOL_TRC_ARIB_STD_B67) > +ctx->params->preferredTransferCharacteristics = > ctx->params->vui.transferCharacteristics; > +#endif isn't the point of preferred_transfer_characteristics to have the Arib value at the same time the standard VUI trc field contains a value like BT2020 instead, for device backwards compat purposes? If both have the Arib value, then it seems redundant. > ctx->params->vui.matrixCoeffs= avctx->colorspace; > } > > ___ 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".
[FFmpeg-devel] [PATCH] lavc/x265: set preferred_transfer_characteristics for HLG
"HEVC HDR UHDTV Bitstreams using HLG10 shall also contain the alternative_transfer_characteristics SEI message. The alternative_transfer_characteristics SEI message shall be inserted on the HEVC DVB_RAP, and preferred_transfer_characteristics shall be set equal to "18", indicating Recommendation ITU-R BT. 2100 [45] HLG system." Signed-off-by: Zhong Li --- libavcodec/libx265.c | 4 1 file changed, 4 insertions(+) diff --git a/libavcodec/libx265.c b/libavcodec/libx265.c index 4e75077..963c28f 100644 --- a/libavcodec/libx265.c +++ b/libavcodec/libx265.c @@ -159,6 +159,10 @@ static av_cold int libx265_encode_init(AVCodecContext *avctx) // x265 validates the parameters internally ctx->params->vui.colorPrimaries = avctx->color_primaries; ctx->params->vui.transferCharacteristics = avctx->color_trc; +#if X265_BUILD >= 159 +if (avctx->color_trc == AVCOL_TRC_ARIB_STD_B67) +ctx->params->preferredTransferCharacteristics = ctx->params->vui.transferCharacteristics; +#endif ctx->params->vui.matrixCoeffs= avctx->colorspace; } -- 1.8.3.1 ___ 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".
