github.com/cellofellow/gopkg@v0.0.0-20140722061823-eec0544a62ad/image/webp/libwebp/src/utils/quant_levels.h (about)

     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_ */