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 "sharpyuv/sharpyuv.h" 16 #include "src/webp/types.h" 17 18 #ifdef __cplusplus 19 extern "C" { 20 #endif 21 22 // Initializes precomputed tables. Must be called once before calling 23 // SharpYuvGammaToLinear or SharpYuvLinearToGamma. 24 void SharpYuvInitGammaTables(void); 25 26 // Converts a 'bit_depth'-bit gamma color value to a 16-bit linear value. 27 uint32_t SharpYuvGammaToLinear(uint16_t v, int bit_depth, 28 SharpYuvTransferFunctionType transfer_type); 29 30 // Converts a 16-bit linear color value to a 'bit_depth'-bit gamma value. 31 uint16_t SharpYuvLinearToGamma(uint32_t value, int bit_depth, 32 SharpYuvTransferFunctionType transfer_type); 33 34 #ifdef __cplusplus 35 } // extern "C" 36 #endif 37 38 #endif // WEBP_SHARPYUV_SHARPYUV_GAMMA_H_ 39