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zopfli.h revision 1.1 
      1  1.1  tls /*
      2  1.1  tls Copyright 2013 Google Inc. All Rights Reserved.
      3  1.1  tls Author: lode (at) google.com (Lode Vandevenne)
      4  1.1  tls */
      5  1.1  tls 
      6  1.1  tls #ifndef UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_
      7  1.1  tls #define UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_
      8  1.1  tls 
      9  1.1  tls #include <stdlib.h> /* for size_t */
     10  1.1  tls 
     11  1.1  tls /*
     12  1.1  tls Options used throughout the program.
     13  1.1  tls */
     14  1.1  tls typedef struct ZopfliOptions {
     15  1.1  tls   /* Whether to print output */
     16  1.1  tls   int verbose;
     17  1.1  tls 
     18  1.1  tls   /*
     19  1.1  tls   Maximum amount of times to rerun forward and backward pass to optimize LZ77
     20  1.1  tls   compression cost. Good values: 10, 15 for small files, 5 for files over
     21  1.1  tls   several MB in size or it will be too slow.
     22  1.1  tls   */
     23  1.1  tls   int numiterations;
     24  1.1  tls 
     25  1.1  tls   /*
     26  1.1  tls   If true, splits the data in multiple deflate blocks with optimal choice
     27  1.1  tls   for the block boundaries. Block splitting gives better compression. Default:
     28  1.1  tls   true (1).
     29  1.1  tls   */
     30  1.1  tls   int blocksplitting;
     31  1.1  tls 
     32  1.1  tls   /*
     33  1.1  tls   If true, chooses the optimal block split points only after doing the iterative
     34  1.1  tls   LZ77 compression. If false, chooses the block split points first, then does
     35  1.1  tls   iterative LZ77 on each individual block. Depending on the file, either first
     36  1.1  tls   or last gives the best compression. Default: false (0).
     37  1.1  tls   */
     38  1.1  tls   int blocksplittinglast;
     39  1.1  tls 
     40  1.1  tls   /*
     41  1.1  tls   Maximum amount of blocks to split into (0 for unlimited, but this can give
     42  1.1  tls   extreme results that hurt compression on some files). Default value: 15.
     43  1.1  tls   */
     44  1.1  tls   int blocksplittingmax;
     45  1.1  tls } ZopfliOptions;
     46  1.1  tls 
     47  1.1  tls /* Initializes options with default values. */
     48  1.1  tls void ZopfliInitOptions(ZopfliOptions* options);
     49  1.1  tls 
     50  1.1  tls /* Output format */
     51  1.1  tls typedef enum {
     52  1.1  tls   ZOPFLI_FORMAT_GZIP,
     53  1.1  tls   ZOPFLI_FORMAT_ZLIB,
     54  1.1  tls   ZOPFLI_FORMAT_DEFLATE
     55  1.1  tls } ZopfliFormat;
     56  1.1  tls 
     57  1.1  tls /*
     58  1.1  tls Compresses according to the given output format and appends the result to the
     59  1.1  tls output.
     60  1.1  tls 
     61  1.1  tls options: global program options
     62  1.1  tls output_type: the output format to use
     63  1.1  tls out: pointer to the dynamic output array to which the result is appended. Must
     64  1.1  tls   be freed after use
     65  1.1  tls outsize: pointer to the dynamic output array size
     66  1.1  tls */
     67  1.1  tls void ZopfliCompress(const ZopfliOptions* options, ZopfliFormat output_type,
     68  1.1  tls                     const unsigned char* in, size_t insize,
     69  1.1  tls                     unsigned char** out, size_t* outsize);
     70  1.1  tls 
     71  1.1  tls #endif  /* UTIL_COMPRESSION_ZOPFLI_INTERNAL_ZOPFLI_H_ */
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