// 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/opsin_params.h"

#include <stdlib.h>

#include "lib/jxl/linalg.h"

namespace jxl {

#define INVERSE_OPSIN_FROM_SPEC 1

const float* GetOpsinAbsorbanceInverseMatrix() {

#if INVERSE_OPSIN_FROM_SPEC

  return DefaultInverseOpsinAbsorbanceMatrix();

#else   // INVERSE_OPSIN_FROM_SPEC

  // Compute the inverse opsin matrix from the forward matrix. Less precise

  // than taking the values from the specification, but must be used if the

  // forward transform is changed and the spec will require updating.

  static const float* const kInverse = [] {

    static float inverse[9];

    for (int i = 0; i < 9; i++) {

      inverse[i] = kOpsinAbsorbanceMatrix[i];

    }

    Inv3x3Matrix(inverse);

    return inverse;

  }();

  return kInverse;

#endif  // INVERSE_OPSIN_FROM_SPEC

}

void InitSIMDInverseMatrix(const float* JXL_RESTRICT inverse,

                           float* JXL_RESTRICT simd_inverse,

                           float intensity_target) {

  for (size_t i = 0; i < 9; ++i) {

    simd_inverse[4 * i] = simd_inverse[4 * i + 1] = simd_inverse[4 * i + 2] =

        simd_inverse[4 * i + 3] = inverse[i] * (255.0f / intensity_target);

  }

}

}  // namespace jxl