lzo.h 2.36 KB
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/*
 * LZO 1x decompression
 * copyright (c) 2006 Reimar Doeffinger
 *
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 * This file is part of Libav.
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 *
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 * Libav is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * Libav is distributed in the hope that it will be useful,
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 * 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
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 * License along with Libav; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

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#ifndef AVUTIL_LZO_H
#define AVUTIL_LZO_H
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#include <stdint.h>

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/** @name Error flags returned by av_lzo1x_decode
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  * \{ */
//! end of the input buffer reached before decoding finished
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#define AV_LZO_INPUT_DEPLETED 1
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//! decoded data did not fit into output buffer
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#define AV_LZO_OUTPUT_FULL 2
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//! a reference to previously decoded data was wrong
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#define AV_LZO_INVALID_BACKPTR 4
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//! a non-specific error in the compressed bitstream
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#define AV_LZO_ERROR 8
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/** \} */
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#define AV_LZO_INPUT_PADDING 8
#define AV_LZO_OUTPUT_PADDING 12
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/**
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 * @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
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 *
 * Make sure all buffers are appropriately padded, in must provide
 * AV_LZO_INPUT_PADDING, out must provide AV_LZO_OUTPUT_PADDING additional bytes.
 */
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int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen);
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/**
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 * @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
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 *
 * cnt > back is valid, this will copy the bytes we just copied,
 * thus creating a repeating pattern with a period length of back.
 */
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void av_memcpy_backptr(uint8_t *dst, int back, int cnt);

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#endif /* AVUTIL_LZO_H */