[FFmpeg-cvslog] cbs_h264: add support for Film Grain Characteristics SEI messages
James Almer
git at videolan.org
Fri Jul 23 17:09:52 EEST 2021
ffmpeg | branch: master | James Almer <jamrial at gmail.com> | Fri Jul 23 11:05:04 2021 -0300| [41d1dba4d281aafc4c67aa24ddb1798b25f1e27f] | committer: James Almer
cbs_h264: add support for Film Grain Characteristics SEI messages
Signed-off-by: James Almer <jamrial at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=41d1dba4d281aafc4c67aa24ddb1798b25f1e27f
---
libavcodec/cbs_h264.h | 21 +++++++++
libavcodec/cbs_h2645.c | 6 +++
libavcodec/cbs_h264_syntax_template.c | 83 +++++++++++++++++++++++++++++++++++
3 files changed, 110 insertions(+)
diff --git a/libavcodec/cbs_h264.h b/libavcodec/cbs_h264.h
index 5a8641a333..ca9b688c05 100644
--- a/libavcodec/cbs_h264.h
+++ b/libavcodec/cbs_h264.h
@@ -272,6 +272,27 @@ typedef struct H264RawSEIRecoveryPoint {
uint8_t changing_slice_group_idc;
} H264RawSEIRecoveryPoint;
+typedef struct H264RawFilmGrainCharacteristics {
+ uint8_t film_grain_characteristics_cancel_flag;
+ uint8_t film_grain_model_id;
+ uint8_t separate_colour_description_present_flag;
+ uint8_t film_grain_bit_depth_luma_minus8;
+ uint8_t film_grain_bit_depth_chroma_minus8;
+ uint8_t film_grain_full_range_flag;
+ uint8_t film_grain_colour_primaries;
+ uint8_t film_grain_transfer_characteristics;
+ uint8_t film_grain_matrix_coefficients;
+ uint8_t blending_mode_id;
+ uint8_t log2_scale_factor;
+ uint8_t comp_model_present_flag[3];
+ uint8_t num_intensity_intervals_minus1[3];
+ uint8_t num_model_values_minus1[3];
+ uint8_t intensity_interval_lower_bound[3][256];
+ uint8_t intensity_interval_upper_bound[3][256];
+ int16_t comp_model_value[3][256][6];
+ uint8_t film_grain_characteristics_repetition_period;
+} H264RawFilmGrainCharacteristics;
+
typedef struct H264RawSEIDisplayOrientation {
uint8_t display_orientation_cancel_flag;
uint8_t hor_flip;
diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
index 6005d46e0d..61c1e13cf7 100644
--- a/libavcodec/cbs_h2645.c
+++ b/libavcodec/cbs_h2645.c
@@ -1570,6 +1570,12 @@ static const SEIMessageTypeDescriptor cbs_sei_h264_types[] = {
sizeof(H264RawSEIRecoveryPoint),
SEI_MESSAGE_RW(h264, sei_recovery_point),
},
+ {
+ SEI_TYPE_FILM_GRAIN_CHARACTERISTICS,
+ 1, 0,
+ sizeof(H264RawFilmGrainCharacteristics),
+ SEI_MESSAGE_RW(h264, film_grain_characteristics),
+ },
{
SEI_TYPE_DISPLAY_ORIENTATION,
1, 0,
diff --git a/libavcodec/cbs_h264_syntax_template.c b/libavcodec/cbs_h264_syntax_template.c
index 9587f33985..0f8bba4a0d 100644
--- a/libavcodec/cbs_h264_syntax_template.c
+++ b/libavcodec/cbs_h264_syntax_template.c
@@ -719,6 +719,89 @@ static int FUNC(sei_recovery_point)(CodedBitstreamContext *ctx, RWContext *rw,
return 0;
}
+static int FUNC(film_grain_characteristics)(CodedBitstreamContext *ctx, RWContext *rw,
+ H264RawFilmGrainCharacteristics *current,
+ SEIMessageState *state)
+{
+ CodedBitstreamH264Context *h264 = ctx->priv_data;
+ const H264RawSPS *sps;
+ int err, c, i, j;
+
+ HEADER("Film Grain Characteristics");
+
+ sps = h264->active_sps;
+ if (!sps) {
+ // If there is exactly one possible SPS but it is not yet active
+ // then just assume that it should be the active one.
+ int i, k = -1;
+ for (i = 0; i < H264_MAX_SPS_COUNT; i++) {
+ if (h264->sps[i]) {
+ if (k >= 0) {
+ k = -1;
+ break;
+ }
+ k = i;
+ }
+ }
+ if (k >= 0)
+ sps = h264->sps[k];
+ }
+
+ flag(film_grain_characteristics_cancel_flag);
+ if (!current->film_grain_characteristics_cancel_flag) {
+ int filmGrainBitDepth[3];
+
+ u(2, film_grain_model_id, 0, 1);
+ flag(separate_colour_description_present_flag);
+ if (current->separate_colour_description_present_flag) {
+ ub(3, film_grain_bit_depth_luma_minus8);
+ ub(3, film_grain_bit_depth_chroma_minus8);
+ flag(film_grain_full_range_flag);
+ ub(8, film_grain_colour_primaries);
+ ub(8, film_grain_transfer_characteristics);
+ ub(8, film_grain_matrix_coefficients);
+ } else {
+ if (!sps) {
+ av_log(ctx->log_ctx, AV_LOG_ERROR,
+ "No active SPS for film_grain_characteristics.\n");
+ return AVERROR_INVALIDDATA;
+ }
+ infer(film_grain_bit_depth_luma_minus8, sps->bit_depth_luma_minus8);
+ infer(film_grain_bit_depth_chroma_minus8, sps->bit_depth_chroma_minus8);
+ infer(film_grain_full_range_flag, sps->vui.video_full_range_flag);
+ infer(film_grain_colour_primaries, sps->vui.colour_primaries);
+ infer(film_grain_transfer_characteristics, sps->vui.transfer_characteristics);
+ infer(film_grain_matrix_coefficients, sps->vui.matrix_coefficients);
+ }
+
+ filmGrainBitDepth[0] = current->film_grain_bit_depth_luma_minus8 + 8;
+ filmGrainBitDepth[1] =
+ filmGrainBitDepth[2] = current->film_grain_bit_depth_chroma_minus8 + 8;
+
+ u(2, blending_mode_id, 0, 1);
+ ub(4, log2_scale_factor);
+ for (c = 0; c < 3; c++)
+ flags(comp_model_present_flag[c], 1, c);
+ for (c = 0; c < 3; c++) {
+ if (current->comp_model_present_flag[c]) {
+ ubs(8, num_intensity_intervals_minus1[c], 1, c);
+ us(3, num_model_values_minus1[c], 0, 5, 1, c);
+ for (i = 0; i <= current->num_intensity_intervals_minus1[c]; i++) {
+ ubs(8, intensity_interval_lower_bound[c][i], 2, c, i);
+ ubs(8, intensity_interval_upper_bound[c][i], 2, c, i);
+ for (j = 0; j <= current->num_model_values_minus1[c]; j++)
+ ses(comp_model_value[c][i][j], 0 - current->film_grain_model_id * (1 << (filmGrainBitDepth[c] - 1)),
+ ((1 << filmGrainBitDepth[c]) - 1) - current->film_grain_model_id * (1 << (filmGrainBitDepth[c] - 1)),
+ 3, c, i, j);
+ }
+ }
+ }
+ ue(film_grain_characteristics_repetition_period, 0, 16384);
+ }
+
+ return 0;
+}
+
static int FUNC(sei_display_orientation)(CodedBitstreamContext *ctx, RWContext *rw,
H264RawSEIDisplayOrientation *current,
SEIMessageState *sei)
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