media/libwebp/sharpyuv/sharpyuv_gamma.h

   1 // Copyright 2022 Google Inc. All Rights Reserved.
   2 //
   3 // Use of this source code is governed by a BSD-style license
   4 // that can be found in the COPYING file in the root of the source
   5 // tree. An additional intellectual property rights grant can be found
   6 // in the file PATENTS. All contributing project authors may
   7 // be found in the AUTHORS file in the root of the source tree.
   8 // -----------------------------------------------------------------------------
   9 //
  10 // Gamma correction utilities.
  11
  12 #ifndef WEBP_SHARPYUV_SHARPYUV_GAMMA_H_
  13 #define WEBP_SHARPYUV_SHARPYUV_GAMMA_H_
  14
  15 #include "src/webp/types.h"
  16
  17 #ifdef __cplusplus
  18 extern "C" {
  19 #endif
  20
  21 // Initializes precomputed tables. Must be called once before calling
  22 // SharpYuvGammaToLinear or SharpYuvLinearToGamma.
  23 void SharpYuvInitGammaTables(void);
  24
  25 // Converts a gamma color value on 'bit_depth' bits to a 16 bit linear value.
  26 uint32_t SharpYuvGammaToLinear(uint16_t v, int bit_depth);
  27
  28 // Converts a 16 bit linear color value to a gamma value on 'bit_depth' bits.
  29 uint16_t SharpYuvLinearToGamma(uint32_t value, int bit_depth);
  30
  31 #ifdef __cplusplus
  32 }  // extern "C"
  33 #endif
  34
  35 #endif  // WEBP_SHARPYUV_SHARPYUV_GAMMA_H_