libwebp/sharpyuv/sharpyuv_csp.h
Maryla 01a05de1a7 libsharpyuv: add colorspace utilities
Change-Id: I620c8593dc81f39e747de5ed354332adb7278bed
2022-04-08 10:07:22 +02:00

60 lines
1.8 KiB
C

// Copyright 2022 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// Colorspace utilities.
#ifndef WEBP_SHARPYUV_SHARPYUV_CSP_H_
#define WEBP_SHARPYUV_SHARPYUV_CSP_H_
#include "sharpyuv/sharpyuv.h"
#ifdef __cplusplus
extern "C" {
#endif
// Range of YUV values.
typedef enum {
kSharpYuvRangeFull, // YUV values between [0;255] (for 8 bit)
kSharpYuvRangeLimited // Y in [16;235], YUV in [16;240] (for 8 bit)
} SharpYuvRange;
// Constants that define a YUV color space.
typedef struct {
// Kr and Kb are defined such that:
// Y = Kr * r + Kg * g + Kb * b where Kg = 1 - Kr - Kb.
float kr;
float kb;
int bits; // Only 8 bit is supported by SharpYuvConvert.
SharpYuvRange range;
} SharpYuvColorSpace;
// Fills in 'matrix' for the given YUVColorSpace.
void SharpYuvComputeConversionMatrix(const SharpYuvColorSpace* yuv_color_space,
SharpYuvConversionMatrix* matrix);
// Enums for precomputed conversion matrices.
typedef enum {
kSharpYuvMatrixWebp = 0,
kSharpYuvMarixRec601Limited,
kSharpYuvMarixRec601Full,
kSharpYuvMarixRec709Limited,
kSharpYuvMarixRec709Full,
kSharpYuvMarixNum
} SharpYuvMatrixType;
// Returns a pointer to a matrix for one of the predefined colorspaces.
const SharpYuvConversionMatrix* SharpYuvGetConversionMatrix(
SharpYuvMatrixType matrix_type);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // WEBP_SHARPYUV_SHARPYUV_CSP_H_