63 lines
1.6 KiB
C
63 lines
1.6 KiB
C
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/*
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* Common bit i/o utils
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* Copyright (c) 2000, 2001 Fabrice Bellard.
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* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
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*
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* This library 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 of the License, or (at your option) any later version.
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*
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* This library 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 this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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* alternative bitstream reader & writer by Michael Niedermayer <michaelni@gmx.at>
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*/
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/**
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* @file bitstream.c
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* bitstream api.
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*/
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#include <stdio.h>
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#include "bitstream.h"
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/* bit input functions */
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/**
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* reads 0-32 bits.
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*/
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unsigned int get_bits_long(GetBitContext *s, int n){
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if(n<=17) return get_bits(s, n);
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else{
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int ret= get_bits(s, 16) << (n-16);
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return ret | get_bits(s, n-16);
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}
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}
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/**
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* shows 0-32 bits.
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*/
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unsigned int show_bits_long(GetBitContext *s, int n){
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if(n<=17) return show_bits(s, n);
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else{
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GetBitContext gb= *s;
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int ret= get_bits_long(s, n);
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*s= gb;
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return ret;
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}
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}
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void align_get_bits(GetBitContext *s)
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{
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int n= (-get_bits_count(s)) & 7;
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if(n) skip_bits(s, n);
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}
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