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/*
* Copyright (c) 2024, Alliance for Open Media. All rights reserved.
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
// Experimental multilayer metadata defined in CWG-E050.
#ifndef AOM_EXAMPLES_MULTILAYER_METADATA_H_
#define AOM_EXAMPLES_MULTILAYER_METADATA_H_
#include <cstdint>
#include <vector>
namespace libaom_examples {
// std::pair<T, bool> is used to indicate presence of a field,
// like an std::optional (which cannot be used because it's C++17).
// If the boolean is true, then the value is present.
struct ColorProperties {
bool color_range; // true for full range values
uint8_t color_primaries;
uint8_t transfer_characteristics;
uint8_t matrix_coefficients;
};
enum AlphaUse {
ALPHA_STRAIGHT = 0,
ALPHA_PREMULTIPLIED = 1,
ALPHA_SEGMENTATION = 2,
ALPHA_UNSPECIFIED = 3,
};
struct AlphaInformation {
AlphaUse alpha_use_idc; // [0, 7]
uint8_t alpha_bit_depth; // [8, 15]
uint8_t alpha_clip_idc; // [0, 3]
bool alpha_incr_flag;
uint16_t alpha_transparent_value; // [0, 1<<alpha_bit_depth]
uint16_t alpha_opaque_value; // [0, 1<<alpha_bit_depth]
// Relevant for ALPHA_STRAIGHT only.
std::pair<ColorProperties, bool> alpha_color_description;
// Relevant for ALPHA_SEGMENTATION only.
// Must be either empty or have the same size as the number of values between
// alpha_transparent_value and alpha_opaque_value, inclusively.
std::vector<uint16_t> label_type_id;
};
// TODO: maryla - parse floats directly and convert to this wire
// representation at write time.
struct DepthRepresentationElement {
bool sign_flag;
uint8_t exponent; // [0, 126]
uint32_t mantissa;
};
struct DepthInformation {
std::pair<DepthRepresentationElement, bool> z_near;
std::pair<DepthRepresentationElement, bool> z_far;
std::pair<DepthRepresentationElement, bool> d_min;
std::pair<DepthRepresentationElement, bool> d_max;
uint8_t depth_representation_type; // [0, 15]
uint8_t disparity_ref_view_id; // [0, 3]
uint8_t depth_nonlinear_precision; // [8, 23]
// [0, 1<<depth_nonlinear_precision]
std::vector<uint32_t> depth_nonlinear_representation_model;
};
enum MultilayerUseCase {
MULTILAYER_USE_CASE_UNSPECIFIED = 0,
MULTILAYER_USE_CASE_ALPHA = 1,
MULTILAYER_USE_CASE_DEPTH = 2,
MULTILAYER_USE_CASE_STEREO = 3,
MULTILAYER_USE_CASE_STEREO_ALPHA_GLOBAL = 4,
MULTILAYER_USE_CASE_STEREO_DEPTH_GLOBAL = 5,
MULTILAYER_USE_CASE_STEREO_ALPHA = 6,
MULTILAYER_USE_CASE_STEREO_DEPTH = 7,
MULTILAYER_USE_CASE_444 = 8,
MULTILAYER_USE_CASE_420_444 = 9,
MULTILAYER_USE_CASE_444_ALPHA = 10,
MULTILAYER_USE_CASE_444_DEPTH = 11,
};
enum LayerType {
MULTIALYER_LAYER_TYPE_UNSPECIFIED = 0,
MULTIALYER_LAYER_TYPE_TEXTURE = 1,
MULTIALYER_LAYER_TYPE_TEXTURE_1 = 2,
MULTIALYER_LAYER_TYPE_TEXTURE_2 = 3,
MULTIALYER_LAYER_TYPE_TEXTURE_3 = 4,
MULTIALYER_LAYER_TYPE_ALPHA = 5,
MULTIALYER_LAYER_TYPE_DEPTH = 6,
};
enum MultilayerMetadataScope {
SCOPE_UNSPECIFIED = 0,
SCOPE_LOCAL = 1,
SCOPE_GLOBAL = 2,
SCOPE_MIXED = 3,
};
enum MultilayerViewType {
VIEW_UNSPECIFIED = 0,
VIEW_CENTER = 1,
VIEW_LEFT = 2,
VIEW_RIGHT = 3,
};
struct LayerMetadata {
LayerType layer_type; // [0, 31]
bool luma_plane_only_flag;
MultilayerViewType layer_view_type; // [0, 7]
uint8_t group_id; // [0, 3]
uint8_t layer_dependency_idc; // [0, 7]
MultilayerMetadataScope layer_metadata_scope; // [0, 3]
std::pair<ColorProperties, bool> layer_color_description;
// Relevant for MULTIALYER_LAYER_TYPE_ALPHA with SCOPE_GLOBAL or SCOPE_MIXED.
AlphaInformation global_alpha_info;
// Relevant for MULTIALYER_LAYER_TYPE_DEPTH with SCOPE_GLOBAL or SCOPE_MIXED.
DepthInformation global_depth_info;
};
struct MultilayerMetadata {
MultilayerUseCase use_case; // [0, 63]
std::vector<LayerMetadata> layers;
};
// Parses a multilayer metadata file.
// Terminates the process in case of error.
// The metadata is expected to be in a subset of the YAML format supporting
// simple lists and maps with integer values, and comments.
// Does very little validation on the metadata, e.g. does not check that the
// values are in the correct range.
MultilayerMetadata parse_multilayer_file(const char *metadata_path);
// Prints the multilayer metadata to stdout for debugging.
void print_multilayer_metadata(const MultilayerMetadata &multilayer);
} // namespace libaom_examples
#endif // AOM_EXAMPLES_MULTILAYER_METADATA_H_