third_party/libwebp/utils/quant_levels.h

   1 // Copyright 2011 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 // Alpha plane quantization utility
  11 //
  12 // Author:  Vikas Arora (vikasa@google.com)
  13
  14 #ifndef WEBP_UTILS_QUANT_LEVELS_H_
  15 #define WEBP_UTILS_QUANT_LEVELS_H_
  16
  17 #include <stdlib.h>
  18
  19 #include "../webp/types.h"
  20
  21 #ifdef __cplusplus
  22 extern "C" {
  23 #endif
  24
  25 // Replace the input 'data' of size 'width'x'height' with 'num-levels'
  26 // quantized values. If not NULL, 'sse' will contain the sum of squared error.
  27 // Valid range for 'num_levels' is [2, 256].
  28 // Returns false in case of error (data is NULL, or parameters are invalid).
  29 int QuantizeLevels(uint8_t* const data, int width, int height, int num_levels,
  30                    uint64_t* const sse);
  31
  32 #ifdef __cplusplus
  33 }    // extern "C"
  34 #endif
  35
  36 #endif  /* WEBP_UTILS_QUANT_LEVELS_H_ */