lzo.h 2.4 KB

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  1. /*
  2. * LZO 1x decompression
  3. * copyright (c) 2006 Reimar Doeffinger
  4. *
  5. * This file is part of FFmpeg.
  6. *
  7. * FFmpeg is free software; you can redistribute it and/or
  8. * modify it under the terms of the GNU Lesser General Public
  9. * License as published by the Free Software Foundation; either
  10. * version 2.1 of the License, or (at your option) any later version.
  11. *
  12. * FFmpeg is distributed in the hope that it will be useful,
  13. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15. * Lesser General Public License for more details.
  16. *
  17. * You should have received a copy of the GNU Lesser General Public
  18. * License along with FFmpeg; if not, write to the Free Software
  19. * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20. */
  21. #ifndef AVUTIL_LZO_H
  22. #define AVUTIL_LZO_H
  23. #include <stdint.h>
  24. /** \defgroup errflags Error flags returned by av_lzo1x_decode
  25. * \{ */
  26. //! end of the input buffer reached before decoding finished
  27. #define AV_LZO_INPUT_DEPLETED 1
  28. //! decoded data did not fit into output buffer
  29. #define AV_LZO_OUTPUT_FULL 2
  30. //! a reference to previously decoded data was wrong
  31. #define AV_LZO_INVALID_BACKPTR 4
  32. //! a non-specific error in the compressed bitstream
  33. #define AV_LZO_ERROR 8
  34. /** \} */
  35. #define AV_LZO_INPUT_PADDING 8
  36. #define AV_LZO_OUTPUT_PADDING 12
  37. /**
  38. * \brief Decodes LZO 1x compressed data.
  39. * \param out output buffer
  40. * \param outlen size of output buffer, number of bytes left are returned here
  41. * \param in input buffer
  42. * \param inlen size of input buffer, number of bytes left are returned here
  43. * \return 0 on success, otherwise a combination of the error flags above
  44. *
  45. * Make sure all buffers are appropriately padded, in must provide
  46. * AV_LZO_INPUT_PADDING, out must provide AV_LZO_OUTPUT_PADDING additional bytes.
  47. */
  48. int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen);
  49. /**
  50. * \brief deliberately overlapping memcpy implementation
  51. * \param dst destination buffer; must be padded with 12 additional bytes
  52. * \param back how many bytes back we start (the initial size of the overlapping window)
  53. * \param cnt number of bytes to copy, must be >= 0
  54. *
  55. * cnt > back is valid, this will copy the bytes we just copied,
  56. * thus creating a repeating pattern with a period length of back.
  57. */
  58. void av_memcpy_backptr(uint8_t *dst, int back, int cnt);
  59. #endif /* AVUTIL_LZO_H */