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/*
* copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCODEC_UNARY_H
#define AVCODEC_UNARY_H
#include "bitstream.h"
/**
* Get unary code of limited length
* @todo FIXME Slow and ugly
* @param gb GetBitContext
* @param[in] stop The bitstop value (unary code of 1's or 0's)
* @param[in] len Maximum length
* @return Unary length/index
*/
static int get_unary(GetBitContext *gb, int stop, int len)
{
#if 1
int i;
for(i = 0; i < len && get_bits1(gb) != stop; i++);
return i;
/* int i = 0, tmp = !stop;
while (i != len && tmp != stop)
{
tmp = get_bits(gb, 1);
i++;
}
if (i == len && tmp != stop) return len+1;
return i;*/
#else
unsigned int buf;
int log;
OPEN_READER(re, gb);
UPDATE_CACHE(re, gb);
buf=GET_CACHE(re, gb); //Still not sure
if (stop) buf = ~buf;
log= av_log2(-buf); //FIXME: -?
if (log < limit){
LAST_SKIP_BITS(re, gb, log+1);
CLOSE_READER(re, gb);
return log;
}
LAST_SKIP_BITS(re, gb, limit);
CLOSE_READER(re, gb);
return limit;
#endif
}
#endif /* AVCODEC_UNARY_H */
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