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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 "get_bits.h"
/**
* Get unary code of limited length
* @param gb GetBitContext
* @param[in] stop The bitstop value (unary code of 1's or 0's)
* @param[in] len Maximum length
* @return unary 0 based code index. This is also the length in bits of the
* code excluding the stop bit.
* (in case len=1)
* 1 0
* 0 1
* (in case len=2)
* 1 0
* 01 1
* 00 2
* (in case len=3)
* 1 0
* 01 1
* 001 2
* 000 3
*/
static inline int get_unary(GetBitContext *gb, int stop, int len)
{
int i;
for(i = 0; i < len && get_bits1(gb) != stop; i++);
return i;
}
/**
* Get unary code terminated by a 0 with a maximum length of 33
* @param gb GetBitContext
* @return Unary length/index
*/
static inline int get_unary_0_33(GetBitContext *gb)
{
return get_unary(gb, 0, 33);
}
static inline int get_unary_0_9(GetBitContext *gb)
{
return get_unary(gb, 0, 9);
}
#endif /* AVCODEC_UNARY_H */
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