huffman.h 1.5 KB

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  1. /*
  2. * Copyright (C) 2007 Aurelien Jacobs <aurel@gnuage.org>
  3. *
  4. * This file is part of FFmpeg.
  5. *
  6. * FFmpeg is free software; you can redistribute it and/or
  7. * modify it under the terms of the GNU Lesser General Public
  8. * License as published by the Free Software Foundation; either
  9. * version 2.1 of the License, or (at your option) any later version.
  10. *
  11. * FFmpeg is distributed in the hope that it will be useful,
  12. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14. * Lesser General Public License for more details.
  15. *
  16. * You should have received a copy of the GNU Lesser General Public
  17. * License along with FFmpeg; if not, write to the Free Software
  18. * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19. */
  20. /**
  21. * @file
  22. * huffman tree builder and VLC generator
  23. */
  24. #ifndef AVCODEC_HUFFMAN_H
  25. #define AVCODEC_HUFFMAN_H
  26. #include "avcodec.h"
  27. #include "vlc.h"
  28. typedef struct Node {
  29. int16_t sym;
  30. int16_t n0;
  31. uint32_t count;
  32. } Node;
  33. #define FF_HUFFMAN_FLAG_HNODE_FIRST 0x01
  34. #define FF_HUFFMAN_FLAG_ZERO_COUNT 0x02
  35. #define FF_HUFFMAN_BITS 10
  36. typedef int (*HuffCmp)(const void *va, const void *vb);
  37. int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes, int nb_bits,
  38. Node *nodes, HuffCmp cmp, int flags);
  39. int ff_huff_gen_len_table(uint8_t *dst, const uint64_t *stats, int n, int skip0);
  40. #endif /* AVCODEC_HUFFMAN_H */