/*

 * Copyright 2016 Google Inc.

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 * http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include "guetzli/gamma_correct.h"

#include <cmath>

namespace guetzli {

const double* NewSrgb8ToLinearTable() {

  double* table = new double[256];

  int i = 0;

  for (; i < 11; ++i) {

    table[i] = i / 12.92;

  }

  for (; i < 256; ++i) {

    table[i] = 255.0 * std::pow(((i / 255.0) + 0.055) / 1.055, 2.4);

  }

  return table;

}

const double* Srgb8ToLinearTable() {

  static const double* const kSrgb8ToLinearTable = NewSrgb8ToLinearTable();

  return kSrgb8ToLinearTable;

}

}  // namespace guetzli