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/* |
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* copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at> |
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* |
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* This file is part of FFmpeg. |
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* |
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* FFmpeg is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* 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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* FFmpeg is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with FFmpeg; 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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*/ |
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#ifndef AVCODEC_UNARY_H |
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#define AVCODEC_UNARY_H |
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#include "get_bits.h" |
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/** |
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* Get unary code of limited length |
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* @param gb GetBitContext |
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* @param[in] stop The bitstop value (unary code of 1's or 0's) |
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* @param[in] len Maximum length |
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* @return unary 0 based code index. This is also the length in bits of the |
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* code excluding the stop bit. |
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* (in case len=1) |
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* 1 0 |
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* 0 1 |
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* (in case len=2) |
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* 1 0 |
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* 01 1 |
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* 00 2 |
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* (in case len=3) |
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* 1 0 |
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* 01 1 |
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* 001 2 |
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* 000 3 |
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*/ |
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85112288 |
static inline int get_unary(GetBitContext *gb, int stop, int len) |
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{ |
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int i; |
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✓✓✓✓
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for(i = 0; i < len && get_bits1(gb) != stop; i++); |
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85112288 |
return i; |
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} |
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/** |
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* Get unary code terminated by a 0 with a maximum length of 33 |
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* @param gb GetBitContext |
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* @return Unary length/index |
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*/ |
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51335183 |
static inline int get_unary_0_33(GetBitContext *gb) |
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{ |
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51335183 |
return get_unary(gb, 0, 33); |
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} |
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16507234 |
static inline int get_unary_0_9(GetBitContext *gb) |
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{ |
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return get_unary(gb, 0, 9); |
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} |
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#endif /* AVCODEC_UNARY_H */ |