diff options
Diffstat (limited to 'src/include/libplacebo/shaders/film_grain.h')
| -rw-r--r-- | src/include/libplacebo/shaders/film_grain.h | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/src/include/libplacebo/shaders/film_grain.h b/src/include/libplacebo/shaders/film_grain.h new file mode 100644 index 0000000..8a9c78b --- /dev/null +++ b/src/include/libplacebo/shaders/film_grain.h @@ -0,0 +1,137 @@ +/* + * This file is part of libplacebo, which is normally licensed under the terms + * of the LGPL v2.1+. However, this file (film_grain.h) is also available under + * the terms of the more permissive MIT license: + * + * Copyright (c) 2018-2019 Niklas Haas + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#ifndef LIBPLACEBO_SHADERS_FILM_GRAIN_H_ +#define LIBPLACEBO_SHADERS_FILM_GRAIN_H_ + +// Film grain synthesis shaders for AV1 / H.274. + +#include <stdint.h> +#include <stdbool.h> + +#include <libplacebo/colorspace.h> +#include <libplacebo/shaders.h> + +PL_API_BEGIN + +enum pl_film_grain_type { + PL_FILM_GRAIN_NONE = 0, + PL_FILM_GRAIN_AV1, + PL_FILM_GRAIN_H274, + PL_FILM_GRAIN_COUNT, +}; + +// AV1 film grain parameters. For the exact meaning of these, see the AV1 +// specification (section 6.8.20). +struct pl_av1_grain_data { + int num_points_y; + uint8_t points_y[14][2]; // [n][0] = value, [n][1] = scaling + bool chroma_scaling_from_luma; + int num_points_uv[2]; // should be {0} for grayscale images + uint8_t points_uv[2][10][2]; // like points_y for points_uv[0, 1] = u, v + int scaling_shift; + int ar_coeff_lag; + int8_t ar_coeffs_y[24]; + int8_t ar_coeffs_uv[2][25]; + int ar_coeff_shift; + int grain_scale_shift; + int8_t uv_mult[2]; + int8_t uv_mult_luma[2]; + int16_t uv_offset[2]; // 9-bit value, range [-256, 255] + bool overlap; +}; + +// H.274 film grain parameters. For the exact meaning of these, see the H.274 +// specification (section 8.5). +struct pl_h274_grain_data { + int model_id; + int blending_mode_id; + int log2_scale_factor; + bool component_model_present[3]; + uint16_t num_intensity_intervals[3]; + uint8_t num_model_values[3]; + const uint8_t *intensity_interval_lower_bound[3]; + const uint8_t *intensity_interval_upper_bound[3]; + const int16_t (*comp_model_value[3])[6]; +}; + +// Tagged union for film grain data +struct pl_film_grain_data { + enum pl_film_grain_type type; // film grain type + uint64_t seed; // shared seed value + + union { + // Warning: These values are not sanity-checked at all, Invalid grain + // data results in undefined behavior! + struct pl_av1_grain_data av1; + struct pl_h274_grain_data h274; + } params; +}; + +// Options for the `pl_shader_film_grain` call. +struct pl_film_grain_params { + // Required for all film grain types: + struct pl_film_grain_data data; // film grain data + pl_tex tex; // texture to sample from + struct pl_color_repr *repr; // underlying color representation (see notes) + int components; + int component_mapping[4]; // same as `struct pl_plane` + + // Notes for `repr`: + // - repr->bits affects the rounding for grain generation + // - repr->levels affects whether or not we clip to full range or not + // - repr->sys affects the interpretation of channels + // - *repr gets normalized by this shader, which is why it's a pointer + + // Required for PL_FILM_GRAIN_AV1 only: + pl_tex luma_tex; // "luma" texture (see notes) + int luma_comp; // index of luma in `luma_tex` + + // Notes for `luma_tex`: + // - `luma_tex` must be specified if the `tex` does not itself contain the + // "luma-like" component. For XYZ systems, the Y channel is the luma + // component. For RGB systems, the G channel is. +}; + +#define pl_film_grain_params(...) (&(struct pl_film_grain_params) { __VA_ARGS__ }) + +// Test if film grain needs to be applied. This is a helper function that users +// can use to decide whether or not `pl_shader_film_grain` needs to be called, +// based on the given grain metadata. +PL_API bool pl_needs_film_grain(const struct pl_film_grain_params *params); + +// Sample from a texture while applying film grain at the same time. +// `grain_state` must be unique for every plane configuration, as it may +// contain plane-dependent state. +// +// Returns false on any error, or if film grain generation is not supported +// due to GLSL limitations. +PL_API bool pl_shader_film_grain(pl_shader sh, pl_shader_obj *grain_state, + const struct pl_film_grain_params *params); + +PL_API_END + +#endif // LIBPLACEBO_SHADERS_FILM_GRAIN_H_ |