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19 #ifndef AVUTIL_FILM_GRAIN_PARAMS_H
20 #define AVUTIL_FILM_GRAIN_PARAMS_H
24 enum AVFilmGrainParamsType {
25 AV_FILM_GRAIN_PARAMS_NONE = 0,
28 * The union is valid when interpreted as AVFilmGrainAOMParams (codec.aom)
30 AV_FILM_GRAIN_PARAMS_AV1,
34 * This structure describes how to handle film grain synthesis for AOM codecs.
36 * @note The struct must be allocated as part of AVFilmGrainParams using
37 * av_film_grain_params_alloc(). Its size is not a part of the public ABI.
39 typedef struct AVFilmGrainAOMParams {
41 * Number of points, and the scale and value for each point of the
42 * piecewise linear scaling function for the uma plane.
45 uint8_t y_points[14][2 /* value, scaling */];
48 * Signals whether to derive the chroma scaling function from the luma.
49 * Not equivalent to copying the luma values and scales.
51 int chroma_scaling_from_luma;
54 * If chroma_scaling_from_luma is set to 0, signals the chroma scaling
55 * function parameters.
57 int num_uv_points[2 /* cb, cr */];
58 uint8_t uv_points[2 /* cb, cr */][10][2 /* value, scaling */];
61 * Specifies the shift applied to the chroma components. For AV1, its within
62 * [8; 11] and determines the range and quantization of the film grain.
67 * Specifies the auto-regression lag.
72 * Luma auto-regression coefficients. The number of coefficients is given by
73 * 2 * ar_coeff_lag * (ar_coeff_lag + 1).
75 int8_t ar_coeffs_y[24];
78 * Chroma auto-regression coefficients. The number of coefficients is given by
79 * 2 * ar_coeff_lag * (ar_coeff_lag + 1) + !!num_y_points.
81 int8_t ar_coeffs_uv[2 /* cb, cr */][25];
84 * Specifies the range of the auto-regressive coefficients. Values of 6,
85 * 7, 8 and so on represent a range of [-2, 2), [-1, 1), [-0.5, 0.5) and
86 * so on. For AV1 must be between 6 and 9.
91 * Signals the down shift applied to the generated gaussian numbers during
94 int grain_scale_shift;
97 * Specifies the luma/chroma multipliers for the index to the component
100 int uv_mult[2 /* cb, cr */];
101 int uv_mult_luma[2 /* cb, cr */];
104 * Offset used for component scaling function. For AV1 its a 9-bit value
105 * with a range [-256, 255]
107 int uv_offset[2 /* cb, cr */];
110 * Signals whether to overlap film grain blocks.
115 * Signals to clip to limited color levels after film grain application.
117 int limit_output_range;
118 } AVFilmGrainAOMParams;
121 * This structure describes how to handle film grain synthesis in video
122 * for specific codecs. Must be present on every frame where film grain is
123 * meant to be synthesised for correct presentation.
125 * @note The struct must be allocated with av_film_grain_params_alloc() and
126 * its size is not a part of the public ABI.
128 typedef struct AVFilmGrainParams {
130 * Specifies the codec for which this structure is valid.
132 enum AVFilmGrainParamsType type;
135 * Seed to use for the synthesis process, if the codec allows for it.
140 * Additional fields may be added both here and in any structure included.
141 * If a codec's film grain structure differs slightly over another
142 * codec's, fields within may change meaning depending on the type.
145 AVFilmGrainAOMParams aom;
150 * Allocate an AVFilmGrainParams structure and set its fields to
151 * default values. The resulting struct can be freed using av_freep().
152 * If size is not NULL it will be set to the number of bytes allocated.
154 * @return An AVFilmGrainParams filled with default values or NULL
157 AVFilmGrainParams *av_film_grain_params_alloc(size_t *size);
160 * Allocate a complete AVFilmGrainParams and add it to the frame.
162 * @param frame The frame which side data is added to.
164 * @return The AVFilmGrainParams structure to be filled by caller.
166 AVFilmGrainParams *av_film_grain_params_create_side_data(AVFrame *frame);
168 #endif /* AVUTIL_FILM_GRAIN_PARAMS_H */