RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

h264: Add support for alternative transfer characterics SEI 

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.giovara@gmail.com>
This commit is contained in:
Vittorio Giovara 2017-06-09 17:27:22 -04:00
parent 9042402ec7
commit 8c34a2024d
3 changed files with 25 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
libavcodec/h264_sei.c
View File

@ -382,6 +382,14 @@ static int decode_green_metadata(H264SEIGreenMetaData *h, GetBitContext *gb)
return 0;
}
static int decode_alternative_transfer(H264SEIAlternativeTransfer *h,
GetBitContext *gb)
{
h->present = 1;
h->preferred_transfer_characteristics = get_bits(gb, 8);
return 0;
}
int ff_h264_sei_decode(H264SEIContext *h, GetBitContext *gb,
const H264ParamSets *ps, void *logctx)
{
@ -437,6 +445,9 @@ int ff_h264_sei_decode(H264SEIContext *h, GetBitContext *gb,
case SEI_TYPE_GREEN_METADATA:
ret = decode_green_metadata(&h->green_metadata, gb);
break;
case SEI_TYPE_ALTERNATIVE_TRANSFER:
ret = decode_alternative_transfer(&h->alternative_transfer, gb);
break;
default:
av_log(logctx, AV_LOG_DEBUG, "unknown SEI type %d\n", type);
}

9
libavcodec/h264_sei.h
View File

@ -32,7 +32,8 @@ typedef enum {
SEI_TYPE_RECOVERY_POINT = 6, ///< recovery point (frame # to decoder sync)
SEI_TYPE_FRAME_PACKING = 45, ///< frame packing arrangement
SEI_TYPE_DISPLAY_ORIENTATION = 47, ///< display orientation
SEI_TYPE_GREEN_METADATA = 56 ///< GreenMPEG information
SEI_TYPE_GREEN_METADATA = 56, ///< GreenMPEG information
SEI_TYPE_ALTERNATIVE_TRANSFER = 147, ///< alternative transfer
} SEI_Type;
/**
@ -144,6 +145,11 @@ typedef struct H264SEIGreenMetaData {
uint16_t xsd_metric_value;
} H264SEIGreenMetaData;
typedef struct H264SEIAlternativeTransfer {
int present;
int preferred_transfer_characteristics;
} H264SEIAlternativeTransfer;
typedef struct H264SEIContext {
H264SEIPictureTiming picture_timing;
H264SEIAFD afd;
@ -154,6 +160,7 @@ typedef struct H264SEIContext {
H264SEIFramePacking frame_packing;
H264SEIDisplayOrientation display_orientation;
H264SEIGreenMetaData green_metadata;
H264SEIAlternativeTransfer alternative_transfer;
} H264SEIContext;
struct H264ParamSets;

6
libavcodec/h264_slice.c
View File

@ -1287,6 +1287,12 @@ static int h264_export_frame_props(H264Context *h)
h->avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
}
if (h->sei.alternative_transfer.present &&
av_color_transfer_name(h->sei.alternative_transfer.preferred_transfer_characteristics) &&
h->sei.alternative_transfer.preferred_transfer_characteristics != AVCOL_TRC_UNSPECIFIED) {
h->avctx->color_trc = cur->f->color_trc = h->sei.alternative_transfer.preferred_transfer_characteristics;
}
return 0;
}