On 6/13/17 8:54 PM, Vittorio Giovara wrote: > The use of this SEI is for backward compatibility in HLG HDR systems: > older devices that cannot interpret the "arib-std-b67" transfer will > get the compatible transfer (usually bt709 or bt2020) from the VUI, > while newer devices that can interpret HDR will read the SEI and use > its value instead. > > Signed-off-by: Vittorio Giovara <vittorio.giov...@gmail.com> > --- > Expanded commit log and better validated the SEI contents. > Vittorio > > libavcodec/hevc_sei.c | 9 +++++++++ > libavcodec/hevc_sei.h | 7 +++++++ > libavcodec/hevcdec.c | 6 ++++++ > 3 files changed, 22 insertions(+) > > diff --git a/libavcodec/hevc_sei.c b/libavcodec/hevc_sei.c > index 153d211b4b..0a5d4440bf 100644 > --- a/libavcodec/hevc_sei.c > +++ b/libavcodec/hevc_sei.c > @@ -86,6 +86,13 @@ static int > decode_nal_sei_display_orientation(HEVCSEIDisplayOrientation *s, GetB > return 0; > } > > +static int decode_nal_sei_alternative_transfer(HEVCSEIAlternativeTransfer > *s, GetBitContext *gb) > +{ > + s->present = 1; > + s->preferred_transfer_characteristics = get_bits(gb, 8); > + return 0; > +} > + > static int decode_nal_sei_prefix(GetBitContext *gb, void *logctx, HEVCSEI *s, > int type, int size) > { > @@ -96,6 +103,8 @@ static int decode_nal_sei_prefix(GetBitContext *gb, void > *logctx, HEVCSEI *s, > return decode_nal_sei_frame_packing_arrangement(&s->frame_packing, > gb); > case HEVC_SEI_TYPE_DISPLAY_ORIENTATION: > return decode_nal_sei_display_orientation(&s->display_orientation, > gb); > + case HEVC_SEI_TYPE_ALTERNATIVE_TRANSFER_CHARACTERISTICS: > + return decode_nal_sei_alternative_transfer(&s->alternative_transfer, > gb); > default: > av_log(logctx, AV_LOG_DEBUG, "Skipped PREFIX SEI %d\n", type); > skip_bits_long(gb, 8 * size); > diff --git a/libavcodec/hevc_sei.h b/libavcodec/hevc_sei.h > index b699fef45d..e4aeac1fbe 100644 > --- a/libavcodec/hevc_sei.h > +++ b/libavcodec/hevc_sei.h > @@ -54,6 +54,7 @@ typedef enum { > HEVC_SEI_TYPE_REGION_REFRESH_INFO = 134, > HEVC_SEI_TYPE_MASTERING_DISPLAY_INFO = 137, > HEVC_SEI_TYPE_CONTENT_LIGHT_LEVEL_INFO = 144, > + HEVC_SEI_TYPE_ALTERNATIVE_TRANSFER_CHARACTERISTICS = 147, > } HEVC_SEI_Type; > > typedef struct HEVCSEIPictureHash { > @@ -74,10 +75,16 @@ typedef struct HEVCSEIDisplayOrientation { > int hflip, vflip; > } HEVCSEIDisplayOrientation; > > +typedef struct HEVCSEIAlternativeTransfer { > + int present; > + int preferred_transfer_characteristics; > +} HEVCSEIAlternativeTransfer; > + > typedef struct HEVCSEI { > HEVCSEIPictureHash picture_hash; > HEVCSEIFramePacking frame_packing; > HEVCSEIDisplayOrientation display_orientation; > + HEVCSEIAlternativeTransfer alternative_transfer; > } HEVCSEI; > > int ff_hevc_decode_nal_sei(GetBitContext *gb, void *logctx, HEVCSEI *s, > diff --git a/libavcodec/hevcdec.c b/libavcodec/hevcdec.c > index 7a9182af9b..ac0b1a3c1d 100644 > --- a/libavcodec/hevcdec.c > +++ b/libavcodec/hevcdec.c > @@ -2407,6 +2407,12 @@ static int set_side_data(HEVCContext *s) > s->sei.display_orientation.vflip); > } > > + if (s->sei.alternative_transfer.present && > + > av_color_transfer_name(s->sei.alternative_transfer.preferred_transfer_characteristics) > && > + s->sei.alternative_transfer.preferred_transfer_characteristics != > AVCOL_TRC_UNSPECIFIED) { > + s->avctx->color_trc = > s->sei.alternative_transfer.preferred_transfer_characteristics; > + } > + > return 0; > } > >
Still ok. lu _______________________________________________ libav-devel mailing list libav-devel@libav.org https://lists.libav.org/mailman/listinfo/libav-devel