chromium/third_party/libwebp/src/sharpyuv/sharpyuv_csp.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.

#include "sharpyuv/sharpyuv_csp.h"

#include <assert.h>
#include <math.h>
#include <stddef.h>

static int ToFixed16(float f) { … }

void SharpYuvComputeConversionMatrix(const SharpYuvColorSpace* yuv_color_space,
                                     SharpYuvConversionMatrix* matrix) { … }

// Matrices are in YUV_FIX fixed point precision.
// WebP's matrix, similar but not identical to kRec601LimitedMatrix.
static const SharpYuvConversionMatrix kWebpMatrix = …;
// Kr=0.2990f Kb=0.1140f bits=8 range=kSharpYuvRangeLimited
static const SharpYuvConversionMatrix kRec601LimitedMatrix = …;
// Kr=0.2990f Kb=0.1140f bits=8 range=kSharpYuvRangeFull
static const SharpYuvConversionMatrix kRec601FullMatrix = …;
// Kr=0.2126f Kb=0.0722f bits=8 range=kSharpYuvRangeLimited
static const SharpYuvConversionMatrix kRec709LimitedMatrix = …;
// Kr=0.2126f Kb=0.0722f bits=8 range=kSharpYuvRangeFull
static const SharpYuvConversionMatrix kRec709FullMatrix = …;

const SharpYuvConversionMatrix* SharpYuvGetConversionMatrix(
    SharpYuvMatrixType matrix_type) { … }