ffmpeg/libavutil/lzo.h

67 lines
2.4 KiB
C

/*
* LZO 1x decompression
* copyright (c) 2006 Reimar Doeffinger
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVUTIL_LZO_H
#define AVUTIL_LZO_H
#include <stdint.h>
/** @name Error flags returned by av_lzo1x_decode
* \{ */
//! end of the input buffer reached before decoding finished
#define AV_LZO_INPUT_DEPLETED 1
//! decoded data did not fit into output buffer
#define AV_LZO_OUTPUT_FULL 2
//! a reference to previously decoded data was wrong
#define AV_LZO_INVALID_BACKPTR 4
//! a non-specific error in the compressed bitstream
#define AV_LZO_ERROR 8
/** \} */
#define AV_LZO_INPUT_PADDING 8
#define AV_LZO_OUTPUT_PADDING 12
/**
* @brief Decodes LZO 1x compressed data.
* @param out output buffer
* @param outlen size of output buffer, number of bytes left are returned here
* @param in input buffer
* @param inlen size of input buffer, number of bytes left are returned here
* @return 0 on success, otherwise a combination of the error flags above
*
* Make sure all buffers are appropriately padded, in must provide
* AV_LZO_INPUT_PADDING, out must provide AV_LZO_OUTPUT_PADDING additional bytes.
*/
int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen);
/**
* @brief deliberately overlapping memcpy implementation
* @param dst destination buffer; must be padded with 12 additional bytes
* @param back how many bytes back we start (the initial size of the overlapping window)
* @param cnt number of bytes to copy, must be >= 0
*
* cnt > back is valid, this will copy the bytes we just copied,
* thus creating a repeating pattern with a period length of back.
*/
void av_memcpy_backptr(uint8_t *dst, int back, int cnt);
#endif /* AVUTIL_LZO_H */