libwebp/src/utils/color_cache.c

// Copyright 2012 Google Inc. All Rights Reserved.
//
// This code is licensed under the same terms as WebM:
//  Software License Agreement:  http://www.webmproject.org/license/software/
//  Additional IP Rights Grant:  http://www.webmproject.org/license/additional/
// -----------------------------------------------------------------------------
//
// Color Cache for WebP Lossless
//
// Author: jyrki@google.com (Jyrki Alakuijala)

#include <assert.h>
#include <stdlib.h>
#include "./color_cache.h"

#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif

//------------------------------------------------------------------------------
// VP8LColorCache.

int VP8LColorCacheInit(VP8LColorCache* const cc, int hash_bits) {
  int hash_size;
  assert(cc != NULL);

  if (hash_bits == 0) hash_bits = 1;
  hash_size = 1 << hash_bits;
  cc->colors_ = (uint32_t*)calloc(hash_size, sizeof(*cc->colors_));
  if (cc->colors_ == NULL) return 0;
  cc->hash_shift_ = 32 - hash_bits;
  return 1;
}

void VP8LColorCacheClear(VP8LColorCache* const cc) {
  if (cc != NULL) {
    free(cc->colors_);
  }
}

void VP8LColorCacheDelete(VP8LColorCache* const cc) {
  VP8LColorCacheClear(cc);
  free(cc);
}

#if defined(__cplusplus) || defined(c_plusplus)
}
#endif