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/*
* $Id: cobs.h,v 1.16 2010/02/05 23:50:22 simakov Exp $
*
* EPSILON - wavelet image compression library.
* Copyright (C) 2006,2007,2010 Alexander Simakov, <xander@entropyware.info>
*
* This file is part of EPSILON
*
* EPSILON 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 3 of the License, or
* (at your option) any later version.
*
* EPSILON 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 EPSILON. If not, see <http://www.gnu.org/licenses/>.
*
* http://epsilon-project.sourceforge.net
*/
/** \file
*
* \brief Byte stuffing
*
* This file contains routines for efficient byte stuffing.
* The algorithm used here called COBS, which is stands for Consistent
* Overhead Byte Stuffing. Byte stuffing is very useful for parallel
* image processing and improves overall system robustness.
*
* \section References
*
* Stuart Cheshire and Mary Baker, "Consistent Overhead Byte Stuffing".
* IEEE/ACM Transactions on Networking. vol. 7 pp. 159-172 April 1999. */
#ifndef __COBS_H__
#define __COBS_H__
#ifdef __cplusplus
extern "C" {
#endif
/** \addtogroup stuffing Byte stuffing */
/*@{*/
#include <common.h>
/** Byte stuffing
*
* This function performes byte stuffing. All zero-valued
* bytes in the \a input_data will be eliminated. The result
* will be stored in the \a output_data. This operation involves
* some marginal data expansion, no more than 0.4% at worst case.
*
* \param input_data Input data
* \param output_data Output data
* \param input_length Input data length
* \param output_length Output data length
*
* \return Number of bytes actually used in the \a output_data
*
* \note Caller must allocate enough space for the \a output_data
* beforehand. This value can be calculated by the following
* formula: \a input_length + (\a input_length / 254) + 1. */
int stuff_data(unsigned char *input_data, unsigned char *output_data,
int input_length, int output_length);
/** Byte unstuffing
*
* This function is inverse to the previous one. It recovers original data.
* The result will be stored in the \a output_data.
*
* \param input_data Input data
* \param output_data Output data
* \param input_length Input data length
* \param output_length Output data length
*
* \return Number of bytes actually used in the \a output_data
*
* \note Caller must allocate enough space for the \a output_data
* beforehand. Safe value is \a input_length. */
int unstuff_data(unsigned char *input_data, unsigned char *output_data,
int input_length, int output_length);
/*@}*/
#ifdef __cplusplus
}
#endif
#endif /* __COBS_H__ */
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