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// Copyright (c) the JPEG XL Project Authors. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "lib/jxl/chroma_from_luma.h"
#include <jxl/memory_manager.h>
#include <cstddef>
#include <cstdlib> // abs
#include <limits>
#include "lib/jxl/base/common.h"
#include "lib/jxl/fields.h"
#include "lib/jxl/image_ops.h"
namespace jxl {
Status ColorCorrelation::DecodeDC(BitReader* br) {
if (br->ReadFixedBits<1>() == 1) {
// All default.
return true;
}
SetColorFactor(U32Coder::Read(kColorFactorDist, br));
JXL_RETURN_IF_ERROR(F16Coder::Read(br, &base_correlation_x_));
if (std::abs(base_correlation_x_) > 4.0f) {
return JXL_FAILURE("Base X correlation is out of range");
}
JXL_RETURN_IF_ERROR(F16Coder::Read(br, &base_correlation_b_));
if (std::abs(base_correlation_b_) > 4.0f) {
return JXL_FAILURE("Base B correlation is out of range");
}
ytox_dc_ = static_cast<int>(br->ReadFixedBits<kBitsPerByte>()) +
std::numeric_limits<int8_t>::min();
ytob_dc_ = static_cast<int>(br->ReadFixedBits<kBitsPerByte>()) +
std::numeric_limits<int8_t>::min();
RecomputeDCFactors();
return true;
}
StatusOr<ColorCorrelationMap> ColorCorrelationMap::Create(
JxlMemoryManager* memory_manager, size_t xsize, size_t ysize, bool XYB) {
ColorCorrelationMap result;
size_t xblocks = DivCeil(xsize, kColorTileDim);
size_t yblocks = DivCeil(ysize, kColorTileDim);
JXL_ASSIGN_OR_RETURN(result.ytox_map,
ImageSB::Create(memory_manager, xblocks, yblocks));
JXL_ASSIGN_OR_RETURN(result.ytob_map,
ImageSB::Create(memory_manager, xblocks, yblocks));
ZeroFillImage(&result.ytox_map);
ZeroFillImage(&result.ytob_map);
if (!XYB) {
result.base_.base_correlation_b_ = 0;
}
result.base_.RecomputeDCFactors();
return result;
}
} // namespace jxl