[FFmpeg-devel] [PATCH v1 01/19] avcodec/cbs_sei_syntax_template: add sei message film_grain_characteristics
toqsxw at gmail.com
toqsxw at gmail.com
Tue Apr 1 20:15:58 EEST 2025
From: Wu Jianhua <toqsxw at outlook.com>
Signed-off-by: Wu Jianhua <toqsxw at outlook.com>
---
libavcodec/cbs_h2645.c | 6 ++++
libavcodec/cbs_sei.h | 21 +++++++++++
libavcodec/cbs_sei_syntax_template.c | 53 ++++++++++++++++++++++++++++
3 files changed, 80 insertions(+)
diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
index 369e3ac876..768181874c 100644
--- a/libavcodec/cbs_h2645.c
+++ b/libavcodec/cbs_h2645.c
@@ -2187,6 +2187,12 @@ static const SEIMessageTypeDescriptor cbs_sei_common_types[] = {
sizeof(SEIRawAmbientViewingEnvironment),
SEI_MESSAGE_RW(sei, ambient_viewing_environment),
},
+ {
+ SEI_TYPE_FILM_GRAIN_CHARACTERISTICS,
+ 1, 0,
+ sizeof(SEIRawFilmGrainCharacteristics),
+ SEI_MESSAGE_RW(sei, film_grain_characteristics),
+ },
SEI_MESSAGE_TYPE_END,
};
diff --git a/libavcodec/cbs_sei.h b/libavcodec/cbs_sei.h
index 15ef3415ab..a0fb004ecd 100644
--- a/libavcodec/cbs_sei.h
+++ b/libavcodec/cbs_sei.h
@@ -97,6 +97,27 @@ typedef struct SEIRawAmbientViewingEnvironment {
uint16_t ambient_light_y;
} SEIRawAmbientViewingEnvironment;
+typedef struct SEIRawFilmGrainCharacteristics {
+ uint8_t fg_characteristics_cancel_flag;
+ uint8_t fg_model_id;
+ uint8_t fg_separate_colour_description_present_flag;
+ uint8_t fg_bit_depth_luma_minus8;
+ uint8_t fg_bit_depth_chroma_minus8;
+ uint8_t fg_full_range_flag;
+ uint8_t fg_colour_primaries;
+ uint8_t fg_transfer_characteristics;
+ uint8_t fg_matrix_coeffs;
+ uint8_t fg_blending_mode_id;
+ uint8_t fg_log2_scale_factor;
+ uint8_t fg_comp_model_present_flag[3];
+ uint8_t fg_num_intensity_intervals_minus1[3];
+ uint8_t fg_num_model_values_minus1[3];
+ uint8_t fg_intensity_interval_lower_bound[3][256];
+ uint8_t fg_intensity_interval_upper_bound[3][256];
+ int16_t fg_comp_model_value[3][256][6];
+ uint8_t fg_characteristics_persistence_flag;
+} SEIRawFilmGrainCharacteristics;
+
typedef struct SEIRawMessage {
uint32_t payload_type;
uint32_t payload_size;
diff --git a/libavcodec/cbs_sei_syntax_template.c b/libavcodec/cbs_sei_syntax_template.c
index 0205bb47aa..b105299cd9 100644
--- a/libavcodec/cbs_sei_syntax_template.c
+++ b/libavcodec/cbs_sei_syntax_template.c
@@ -224,6 +224,59 @@ SEI_FUNC(ambient_viewing_environment,
return 0;
}
+SEI_FUNC(film_grain_characteristics,
+ (CodedBitstreamContext *ctx, RWContext *rw,
+ SEIRawFilmGrainCharacteristics *current,
+ SEIMessageState *state))
+{
+ int err, c, i, j;
+
+ HEADER("Film Grain Characteristics");
+
+ flag(fg_characteristics_cancel_flag);
+ if (!current->fg_characteristics_cancel_flag) {
+ int filmGrainBitDepth[3];
+
+ u(2, fg_model_id, 0, 1);
+ flag(fg_separate_colour_description_present_flag);
+ if (current->fg_separate_colour_description_present_flag) {
+ ub(3, fg_bit_depth_luma_minus8);
+ ub(3, fg_bit_depth_chroma_minus8);
+ flag(fg_full_range_flag);
+ ub(8, fg_colour_primaries);
+ ub(8, fg_transfer_characteristics);
+ ub(8, fg_matrix_coeffs);
+ }
+
+ filmGrainBitDepth[0] = current->fg_bit_depth_luma_minus8 + 8;
+ filmGrainBitDepth[1] =
+ filmGrainBitDepth[2] = current->fg_bit_depth_chroma_minus8 + 8;
+
+ u(2, fg_blending_mode_id, 0, 1);
+ ub(4, fg_log2_scale_factor);
+ for (c = 0; c < 3; c++)
+ flags(fg_comp_model_present_flag[c], 1, c);
+
+ for (c = 0; c < 3; c++) {
+ if (current->fg_comp_model_present_flag[c]) {
+ ubs(8, fg_num_intensity_intervals_minus1[c], 1, c);
+ us(3, fg_num_model_values_minus1[c], 0, 5, 1, c);
+ for (i = 0; i <= current->fg_num_intensity_intervals_minus1[c]; i++) {
+ ubs(8, fg_intensity_interval_lower_bound[c][i], 2, c, i);
+ ubs(8, fg_intensity_interval_upper_bound[c][i], 2, c, i);
+ for (j = 0; j <= current->fg_num_model_values_minus1[c]; j++)
+ ses(fg_comp_model_value[c][i][j], 0 - current->fg_model_id * (1 << (filmGrainBitDepth[c] - 1)),
+ ((1 << filmGrainBitDepth[c]) - 1) - current->fg_model_id * (1 << (filmGrainBitDepth[c] - 1)),
+ 3, c, i, j);
+ }
+ }
+ }
+ flag(fg_characteristics_persistence_flag);
+ }
+
+ return 0;
+}
+
static int FUNC(message)(CodedBitstreamContext *ctx, RWContext *rw,
SEIRawMessage *current)
{
--
2.44.0.windows.1
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