2006-09-10 14:02:42 +00:00
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/*
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* copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
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*
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2011-03-18 17:35:10 +00:00
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* This file is part of Libav.
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2006-10-07 15:30:46 +00:00
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*
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2011-03-18 17:35:10 +00:00
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* Libav is free software; you can redistribute it and/or
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2006-09-10 14:02:42 +00:00
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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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2006-10-07 15:30:46 +00:00
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* version 2.1 of the License, or (at your option) any later version.
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2006-09-10 14:02:42 +00:00
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*
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2011-03-18 17:35:10 +00:00
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* Libav is distributed in the hope that it will be useful,
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2006-09-10 14:02:42 +00:00
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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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2011-03-18 17:35:10 +00:00
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* License along with Libav; if not, write to the Free Software
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2006-09-10 14:02:42 +00:00
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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2004-12-29 17:50:25 +00:00
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/**
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2010-04-20 14:45:34 +00:00
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* @file
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2009-04-13 16:20:26 +00:00
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* bitstream reader API header.
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2004-12-29 17:50:25 +00:00
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*/
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2009-04-13 16:20:26 +00:00
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#ifndef AVCODEC_GET_BITS_H
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#define AVCODEC_GET_BITS_H
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2004-12-29 17:50:25 +00:00
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2007-06-16 22:59:13 +00:00
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#include <stdint.h>
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2013-01-20 15:10:24 +00:00
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2008-05-09 11:56:36 +00:00
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#include "libavutil/common.h"
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#include "libavutil/intreadwrite.h"
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#include "libavutil/log.h"
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2009-03-03 02:00:47 +00:00
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#include "mathops.h"
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2006-08-28 18:44:49 +00:00
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2011-12-16 21:42:04 +00:00
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/*
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* Safe bitstream reading:
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* optionally, the get_bits API can check to ensure that we
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* don't read past input buffer boundaries. This is protected
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* with CONFIG_SAFE_BITSTREAM_READER at the global level, and
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* then below that with UNCHECKED_BITSTREAM_READER at the per-
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* decoder level. This means that decoders that check internally
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* can "#define UNCHECKED_BITSTREAM_READER 1" to disable
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* overread checks.
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* Boundary checking causes a minor performance penalty so for
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* applications that won't want/need this, it can be disabled
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* globally using "#define CONFIG_SAFE_BITSTREAM_READER 0".
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*/
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#ifndef UNCHECKED_BITSTREAM_READER
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#define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
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#endif
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2004-12-29 17:50:25 +00:00
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typedef struct GetBitContext {
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const uint8_t *buffer, *buffer_end;
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int index;
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int size_in_bits;
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2011-12-16 21:42:04 +00:00
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#if !UNCHECKED_BITSTREAM_READER
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int size_in_bits_plus8;
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#endif
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2004-12-29 17:50:25 +00:00
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} GetBitContext;
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#define VLC_TYPE int16_t
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typedef struct VLC {
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int bits;
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VLC_TYPE (*table)[2]; ///< code, bits
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int table_size, table_allocated;
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} VLC;
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typedef struct RL_VLC_ELEM {
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int16_t level;
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int8_t len;
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uint8_t run;
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} RL_VLC_ELEM;
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/* Bitstream reader API docs:
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2013-01-20 15:10:24 +00:00
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* name
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* arbitrary name which is used as prefix for the internal variables
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*
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* gb
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* getbitcontext
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*
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* OPEN_READER(name, gb)
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* load gb into local variables
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*
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* CLOSE_READER(name, gb)
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* store local vars in gb
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*
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* UPDATE_CACHE(name, gb)
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* Refill the internal cache from the bitstream.
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* After this call at least MIN_CACHE_BITS will be available.
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*
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* GET_CACHE(name, gb)
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* Will output the contents of the internal cache,
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* next bit is MSB of 32 or 64 bit (FIXME 64bit).
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*
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* SHOW_UBITS(name, gb, num)
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* Will return the next num bits.
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*
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* SHOW_SBITS(name, gb, num)
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* Will return the next num bits and do sign extension.
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*
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* SKIP_BITS(name, gb, num)
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* Will skip over the next num bits.
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* Note, this is equivalent to SKIP_CACHE; SKIP_COUNTER.
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*
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* SKIP_CACHE(name, gb, num)
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* Will remove the next num bits from the cache (note SKIP_COUNTER
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* MUST be called before UPDATE_CACHE / CLOSE_READER).
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*
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* SKIP_COUNTER(name, gb, num)
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* Will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS).
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*
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* LAST_SKIP_BITS(name, gb, num)
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* Like SKIP_BITS, to be used if next call is UPDATE_CACHE or CLOSE_READER.
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*
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* For examples see get_bits, show_bits, skip_bits, get_vlc.
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*/
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2004-12-29 17:50:25 +00:00
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2011-12-16 21:19:50 +00:00
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#ifdef LONG_BITSTREAM_READER
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# define MIN_CACHE_BITS 32
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#else
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2004-12-29 17:50:25 +00:00
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# define MIN_CACHE_BITS 25
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2011-12-16 21:19:50 +00:00
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#endif
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2004-12-29 17:50:25 +00:00
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2014-08-22 12:37:39 +00:00
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#define OPEN_READER_NOSIZE(name, gb) \
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2013-01-20 15:10:24 +00:00
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unsigned int name ## _index = (gb)->index; \
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unsigned int av_unused name ## _cache = 0
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2004-12-29 17:50:25 +00:00
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2014-08-22 12:37:39 +00:00
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#if UNCHECKED_BITSTREAM_READER
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#define OPEN_READER(name, gb) OPEN_READER_NOSIZE(name, gb)
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2014-08-22 10:36:12 +00:00
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#define BITS_AVAILABLE(name, gb) 1
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2012-02-22 20:09:33 +00:00
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#else
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#define OPEN_READER(name, gb) \
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2014-08-22 12:37:39 +00:00
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OPEN_READER_NOSIZE(name, gb); \
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unsigned int name ## _size_plus8 = (gb)->size_in_bits_plus8
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2012-02-22 20:09:33 +00:00
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2014-08-22 10:36:12 +00:00
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#define BITS_AVAILABLE(name, gb) name ## _index < name ## _size_plus8
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2012-02-22 20:09:33 +00:00
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#endif
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2013-01-20 15:10:24 +00:00
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#define CLOSE_READER(name, gb) (gb)->index = name ## _index
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2011-12-17 01:05:35 +00:00
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2011-12-22 15:33:31 +00:00
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#ifdef BITSTREAM_READER_LE
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2004-12-29 17:50:25 +00:00
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2011-12-16 21:19:50 +00:00
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# ifdef LONG_BITSTREAM_READER
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2013-01-20 15:10:24 +00:00
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# define UPDATE_CACHE(name, gb) name ## _cache = \
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AV_RL64((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
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2011-12-16 21:19:50 +00:00
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# else
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2013-01-20 15:10:24 +00:00
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# define UPDATE_CACHE(name, gb) name ## _cache = \
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AV_RL32((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
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2011-12-16 21:19:50 +00:00
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# endif
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2005-05-11 01:46:13 +00:00
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2013-01-20 15:10:24 +00:00
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# define SKIP_CACHE(name, gb, num) name ## _cache >>= (num)
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2011-12-17 01:05:35 +00:00
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#else
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2011-12-16 21:19:50 +00:00
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# ifdef LONG_BITSTREAM_READER
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2013-01-20 15:10:24 +00:00
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# define UPDATE_CACHE(name, gb) name ## _cache = \
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AV_RB64((gb)->buffer + (name ## _index >> 3)) >> (32 - (name ## _index & 7))
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2011-12-16 21:19:50 +00:00
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# else
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2013-01-20 15:10:24 +00:00
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# define UPDATE_CACHE(name, gb) name ## _cache = \
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AV_RB32((gb)->buffer + (name ## _index >> 3)) << (name ## _index & 7)
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2011-12-16 21:19:50 +00:00
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# endif
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2004-12-29 17:50:25 +00:00
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2013-01-20 15:10:24 +00:00
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# define SKIP_CACHE(name, gb, num) name ## _cache <<= (num)
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2011-12-17 01:05:35 +00:00
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#endif
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2004-12-29 17:50:25 +00:00
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2011-12-16 21:42:04 +00:00
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#if UNCHECKED_BITSTREAM_READER
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2013-01-20 15:10:24 +00:00
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# define SKIP_COUNTER(name, gb, num) name ## _index += (num)
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2011-12-16 21:42:04 +00:00
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#else
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# define SKIP_COUNTER(name, gb, num) \
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2013-01-20 15:10:24 +00:00
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name ## _index = FFMIN(name ## _size_plus8, name ## _index + (num))
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2011-12-16 21:42:04 +00:00
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#endif
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2004-12-29 17:50:25 +00:00
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2013-01-20 15:10:24 +00:00
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#define SKIP_BITS(name, gb, num) \
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do { \
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2011-01-23 01:56:27 +00:00
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SKIP_CACHE(name, gb, num); \
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SKIP_COUNTER(name, gb, num); \
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} while (0)
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2004-12-29 17:50:25 +00:00
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2011-12-17 01:05:35 +00:00
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#define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
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2004-12-29 17:50:25 +00:00
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2011-12-22 15:33:31 +00:00
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#ifdef BITSTREAM_READER_LE
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2013-01-20 15:10:24 +00:00
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# define SHOW_UBITS(name, gb, num) zero_extend(name ## _cache, num)
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# define SHOW_SBITS(name, gb, num) sign_extend(name ## _cache, num)
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2011-12-17 01:05:35 +00:00
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#else
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2013-01-20 15:10:24 +00:00
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# define SHOW_UBITS(name, gb, num) NEG_USR32(name ## _cache, num)
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# define SHOW_SBITS(name, gb, num) NEG_SSR32(name ## _cache, num)
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2011-12-17 01:05:35 +00:00
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#endif
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2004-12-29 17:50:25 +00:00
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2013-01-20 15:10:24 +00:00
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#define GET_CACHE(name, gb) ((uint32_t) name ## _cache)
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2004-12-29 17:50:25 +00:00
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2011-12-17 01:05:35 +00:00
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static inline int get_bits_count(const GetBitContext *s)
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{
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2004-12-29 17:50:25 +00:00
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return s->index;
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}
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2006-08-26 10:26:14 +00:00
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2013-01-20 15:10:24 +00:00
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static inline void skip_bits_long(GetBitContext *s, int n)
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{
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2011-12-16 21:42:04 +00:00
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#if UNCHECKED_BITSTREAM_READER
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2006-08-26 11:50:23 +00:00
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s->index += n;
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2011-12-16 21:42:04 +00:00
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#else
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s->index += av_clip(n, -s->index, s->size_in_bits_plus8 - s->index);
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#endif
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2006-08-26 10:26:14 +00:00
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}
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2004-12-29 17:50:25 +00:00
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/**
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* read mpeg1 dc style vlc (sign bit + mantisse with no MSB).
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2005-12-17 18:14:38 +00:00
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* if MSB not set it is negative
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2004-12-29 17:50:25 +00:00
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* @param n length in bits
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*/
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2011-12-17 01:05:35 +00:00
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static inline int get_xbits(GetBitContext *s, int n)
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{
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2006-03-31 20:40:22 +00:00
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register int sign;
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2004-12-29 17:50:25 +00:00
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register int32_t cache;
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2011-01-23 01:24:46 +00:00
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OPEN_READER(re, s);
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UPDATE_CACHE(re, s);
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2011-01-23 01:56:27 +00:00
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cache = GET_CACHE(re, s);
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2013-01-20 15:10:24 +00:00
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sign = ~cache >> 31;
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2011-01-23 01:24:46 +00:00
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LAST_SKIP_BITS(re, s, n);
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CLOSE_READER(re, s);
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2006-03-31 20:40:22 +00:00
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return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
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2004-12-29 17:50:25 +00:00
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}
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2011-12-17 01:05:35 +00:00
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static inline int get_sbits(GetBitContext *s, int n)
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{
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2004-12-29 17:50:25 +00:00
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register int tmp;
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2011-01-23 01:24:46 +00:00
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OPEN_READER(re, s);
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UPDATE_CACHE(re, s);
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2011-01-23 01:56:27 +00:00
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tmp = SHOW_SBITS(re, s, n);
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2011-01-23 01:24:46 +00:00
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LAST_SKIP_BITS(re, s, n);
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CLOSE_READER(re, s);
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2004-12-29 17:50:25 +00:00
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return tmp;
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}
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/**
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2011-01-23 01:18:13 +00:00
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* Read 1-25 bits.
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2004-12-29 17:50:25 +00:00
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*/
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2011-12-17 01:05:35 +00:00
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static inline unsigned int get_bits(GetBitContext *s, int n)
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{
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2004-12-29 17:50:25 +00:00
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register int tmp;
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2011-01-23 01:24:46 +00:00
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OPEN_READER(re, s);
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UPDATE_CACHE(re, s);
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2011-01-23 01:56:27 +00:00
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tmp = SHOW_UBITS(re, s, n);
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2011-01-23 01:24:46 +00:00
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LAST_SKIP_BITS(re, s, n);
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CLOSE_READER(re, s);
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2004-12-29 17:50:25 +00:00
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return tmp;
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}
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/**
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2011-12-07 12:03:53 +00:00
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* Show 1-25 bits.
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2004-12-29 17:50:25 +00:00
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*/
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2011-12-17 01:05:35 +00:00
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static inline unsigned int show_bits(GetBitContext *s, int n)
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{
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2004-12-29 17:50:25 +00:00
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register int tmp;
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2014-08-22 12:37:39 +00:00
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OPEN_READER_NOSIZE(re, s);
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2011-01-23 01:24:46 +00:00
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UPDATE_CACHE(re, s);
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2011-01-23 01:56:27 +00:00
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tmp = SHOW_UBITS(re, s, n);
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2004-12-29 17:50:25 +00:00
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return tmp;
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}
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2011-12-17 01:05:35 +00:00
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static inline void skip_bits(GetBitContext *s, int n)
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{
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2011-01-23 01:24:46 +00:00
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OPEN_READER(re, s);
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UPDATE_CACHE(re, s);
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LAST_SKIP_BITS(re, s, n);
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CLOSE_READER(re, s);
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2004-12-29 17:50:25 +00:00
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}
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2011-12-17 01:05:35 +00:00
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static inline unsigned int get_bits1(GetBitContext *s)
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{
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2011-01-23 01:56:27 +00:00
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unsigned int index = s->index;
|
2013-01-20 15:10:24 +00:00
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|
|
uint8_t result = s->buffer[index >> 3];
|
2011-12-22 15:33:31 +00:00
|
|
|
#ifdef BITSTREAM_READER_LE
|
2011-01-23 01:56:27 +00:00
|
|
|
result >>= index & 7;
|
2013-01-20 15:10:24 +00:00
|
|
|
result &= 1;
|
2005-05-11 01:46:13 +00:00
|
|
|
#else
|
2011-01-23 01:56:27 +00:00
|
|
|
result <<= index & 7;
|
|
|
|
result >>= 8 - 1;
|
2005-05-11 01:46:13 +00:00
|
|
|
#endif
|
2011-12-16 21:42:04 +00:00
|
|
|
#if !UNCHECKED_BITSTREAM_READER
|
|
|
|
if (s->index < s->size_in_bits_plus8)
|
|
|
|
#endif
|
|
|
|
index++;
|
2011-01-23 01:56:27 +00:00
|
|
|
s->index = index;
|
2004-12-29 17:50:25 +00:00
|
|
|
|
|
|
|
return result;
|
|
|
|
}
|
|
|
|
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline unsigned int show_bits1(GetBitContext *s)
|
|
|
|
{
|
2004-12-29 17:50:25 +00:00
|
|
|
return show_bits(s, 1);
|
|
|
|
}
|
|
|
|
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline void skip_bits1(GetBitContext *s)
|
|
|
|
{
|
2004-12-29 17:50:25 +00:00
|
|
|
skip_bits(s, 1);
|
|
|
|
}
|
|
|
|
|
2006-08-28 18:44:49 +00:00
|
|
|
/**
|
2011-12-07 12:03:53 +00:00
|
|
|
* Read 0-32 bits.
|
2006-08-28 18:44:49 +00:00
|
|
|
*/
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline unsigned int get_bits_long(GetBitContext *s, int n)
|
|
|
|
{
|
2013-01-20 15:10:24 +00:00
|
|
|
if (n <= MIN_CACHE_BITS) {
|
2011-12-17 01:05:35 +00:00
|
|
|
return get_bits(s, n);
|
2013-01-20 15:10:24 +00:00
|
|
|
} else {
|
2011-12-22 15:33:31 +00:00
|
|
|
#ifdef BITSTREAM_READER_LE
|
2011-01-23 01:56:27 +00:00
|
|
|
int ret = get_bits(s, 16);
|
2013-01-20 15:10:24 +00:00
|
|
|
return ret | (get_bits(s, n - 16) << 16);
|
2006-09-25 22:47:55 +00:00
|
|
|
#else
|
2013-01-20 15:10:24 +00:00
|
|
|
int ret = get_bits(s, 16) << (n - 16);
|
|
|
|
return ret | get_bits(s, n - 16);
|
2006-09-25 22:47:55 +00:00
|
|
|
#endif
|
2006-08-28 18:44:49 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2012-09-30 00:39:55 +00:00
|
|
|
/*
|
|
|
|
* Read 0-64 bits.
|
|
|
|
*/
|
|
|
|
static inline uint64_t get_bits64(GetBitContext *s, int n)
|
|
|
|
{
|
|
|
|
if (n <= 32) {
|
|
|
|
return get_bits_long(s, n);
|
|
|
|
} else {
|
|
|
|
#ifdef BITSTREAM_READER_LE
|
|
|
|
uint64_t ret = get_bits_long(s, 32);
|
2013-01-20 15:10:24 +00:00
|
|
|
return ret | (uint64_t) get_bits_long(s, n - 32) << 32;
|
2012-09-30 00:39:55 +00:00
|
|
|
#else
|
2013-01-20 15:10:24 +00:00
|
|
|
uint64_t ret = (uint64_t) get_bits_long(s, n - 32) << 32;
|
2012-09-30 00:39:55 +00:00
|
|
|
return ret | get_bits_long(s, 32);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2009-03-03 02:00:47 +00:00
|
|
|
/**
|
2011-12-07 12:03:53 +00:00
|
|
|
* Read 0-32 bits as a signed integer.
|
2009-03-03 02:00:47 +00:00
|
|
|
*/
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline int get_sbits_long(GetBitContext *s, int n)
|
|
|
|
{
|
2009-03-03 02:00:47 +00:00
|
|
|
return sign_extend(get_bits_long(s, n), n);
|
|
|
|
}
|
|
|
|
|
2006-08-28 18:44:49 +00:00
|
|
|
/**
|
2011-12-07 12:03:53 +00:00
|
|
|
* Show 0-32 bits.
|
2006-08-28 18:44:49 +00:00
|
|
|
*/
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline unsigned int show_bits_long(GetBitContext *s, int n)
|
|
|
|
{
|
2013-01-20 15:10:24 +00:00
|
|
|
if (n <= MIN_CACHE_BITS) {
|
2011-12-17 01:05:35 +00:00
|
|
|
return show_bits(s, n);
|
2013-01-20 15:10:24 +00:00
|
|
|
} else {
|
2011-01-23 01:56:27 +00:00
|
|
|
GetBitContext gb = *s;
|
2009-03-02 19:42:31 +00:00
|
|
|
return get_bits_long(&gb, n);
|
2006-08-28 18:44:49 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int check_marker(GetBitContext *s, const char *msg)
|
|
|
|
{
|
2011-01-23 01:56:27 +00:00
|
|
|
int bit = get_bits1(s);
|
|
|
|
if (!bit)
|
2006-08-28 18:44:49 +00:00
|
|
|
av_log(NULL, AV_LOG_INFO, "Marker bit missing %s\n", msg);
|
|
|
|
|
|
|
|
return bit;
|
|
|
|
}
|
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
/**
|
2013-01-13 18:52:45 +00:00
|
|
|
* Initialize GetBitContext.
|
|
|
|
* @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes
|
|
|
|
* larger than the actual read bits because some optimized bitstream
|
|
|
|
* readers read 32 or 64 bit at once and could read over the end
|
2004-12-29 17:50:25 +00:00
|
|
|
* @param bit_size the size of the buffer in bits
|
2013-01-13 18:52:45 +00:00
|
|
|
* @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
|
2004-12-29 17:50:25 +00:00
|
|
|
*/
|
2013-01-13 18:52:45 +00:00
|
|
|
static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
|
|
|
|
int bit_size)
|
2004-12-29 17:50:25 +00:00
|
|
|
{
|
2013-01-13 18:52:45 +00:00
|
|
|
int buffer_size;
|
|
|
|
int ret = 0;
|
|
|
|
|
2013-01-20 04:10:32 +00:00
|
|
|
if (bit_size > INT_MAX - 7 || bit_size < 0 || !buffer) {
|
2005-09-21 23:18:52 +00:00
|
|
|
buffer_size = bit_size = 0;
|
2013-01-20 15:10:24 +00:00
|
|
|
buffer = NULL;
|
|
|
|
ret = AVERROR_INVALIDDATA;
|
2005-09-21 23:18:52 +00:00
|
|
|
}
|
2004-12-29 17:50:25 +00:00
|
|
|
|
2013-01-13 18:52:45 +00:00
|
|
|
buffer_size = (bit_size + 7) >> 3;
|
|
|
|
|
2013-01-20 15:10:24 +00:00
|
|
|
s->buffer = buffer;
|
|
|
|
s->size_in_bits = bit_size;
|
2011-12-16 21:42:04 +00:00
|
|
|
#if !UNCHECKED_BITSTREAM_READER
|
|
|
|
s->size_in_bits_plus8 = bit_size + 8;
|
|
|
|
#endif
|
2013-01-20 15:10:24 +00:00
|
|
|
s->buffer_end = buffer + buffer_size;
|
|
|
|
s->index = 0;
|
|
|
|
|
2013-01-13 18:52:45 +00:00
|
|
|
return ret;
|
2004-12-29 17:50:25 +00:00
|
|
|
}
|
|
|
|
|
2013-01-13 22:37:11 +00:00
|
|
|
/**
|
|
|
|
* Initialize GetBitContext.
|
|
|
|
* @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes
|
|
|
|
* larger than the actual read bits because some optimized bitstream
|
|
|
|
* readers read 32 or 64 bit at once and could read over the end
|
|
|
|
* @param byte_size the size of the buffer in bytes
|
|
|
|
* @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
|
|
|
|
*/
|
|
|
|
static inline int init_get_bits8(GetBitContext *s, const uint8_t *buffer,
|
|
|
|
int byte_size)
|
|
|
|
{
|
|
|
|
if (byte_size > INT_MAX / 8)
|
|
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
return init_get_bits(s, buffer, byte_size * 8);
|
|
|
|
}
|
|
|
|
|
2013-02-11 00:46:07 +00:00
|
|
|
static inline const uint8_t *align_get_bits(GetBitContext *s)
|
2006-08-26 10:26:14 +00:00
|
|
|
{
|
2011-01-23 01:56:27 +00:00
|
|
|
int n = -get_bits_count(s) & 7;
|
2013-01-20 15:10:24 +00:00
|
|
|
if (n)
|
|
|
|
skip_bits(s, n);
|
2013-02-11 00:46:07 +00:00
|
|
|
return s->buffer + (s->index >> 3);
|
2006-08-26 10:26:14 +00:00
|
|
|
}
|
|
|
|
|
2011-01-23 01:56:27 +00:00
|
|
|
#define init_vlc(vlc, nb_bits, nb_codes, \
|
|
|
|
bits, bits_wrap, bits_size, \
|
|
|
|
codes, codes_wrap, codes_size, \
|
|
|
|
flags) \
|
2013-01-20 15:10:24 +00:00
|
|
|
ff_init_vlc_sparse(vlc, nb_bits, nb_codes, \
|
|
|
|
bits, bits_wrap, bits_size, \
|
|
|
|
codes, codes_wrap, codes_size, \
|
|
|
|
NULL, 0, 0, flags)
|
2007-05-24 17:38:56 +00:00
|
|
|
|
2012-02-09 09:37:58 +00:00
|
|
|
int ff_init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes,
|
2013-01-20 15:10:24 +00:00
|
|
|
const void *bits, int bits_wrap, int bits_size,
|
|
|
|
const void *codes, int codes_wrap, int codes_size,
|
|
|
|
const void *symbols, int symbols_wrap, int symbols_size,
|
|
|
|
int flags);
|
2012-02-09 09:37:58 +00:00
|
|
|
void ff_free_vlc(VLC *vlc);
|
2004-12-29 17:50:25 +00:00
|
|
|
|
2013-01-20 15:10:24 +00:00
|
|
|
#define INIT_VLC_LE 2
|
|
|
|
#define INIT_VLC_USE_NEW_STATIC 4
|
2008-05-30 20:00:19 +00:00
|
|
|
|
2013-01-20 15:10:24 +00:00
|
|
|
#define INIT_VLC_STATIC(vlc, bits, a, b, c, d, e, f, g, static_size) \
|
|
|
|
do { \
|
|
|
|
static VLC_TYPE table[static_size][2]; \
|
|
|
|
(vlc)->table = table; \
|
|
|
|
(vlc)->table_allocated = static_size; \
|
|
|
|
init_vlc(vlc, bits, a, b, c, d, e, f, g, INIT_VLC_USE_NEW_STATIC); \
|
|
|
|
} while (0)
|
2008-05-30 20:00:19 +00:00
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
/**
|
2010-02-17 21:20:43 +00:00
|
|
|
* If the vlc code is invalid and max_depth=1, then no bits will be removed.
|
|
|
|
* If the vlc code is invalid and max_depth>1, then the number of bits removed
|
|
|
|
* is undefined.
|
2004-12-29 17:50:25 +00:00
|
|
|
*/
|
2011-12-17 01:05:35 +00:00
|
|
|
#define GET_VLC(code, name, gb, table, bits, max_depth) \
|
|
|
|
do { \
|
2011-01-23 01:56:27 +00:00
|
|
|
int n, nb_bits; \
|
|
|
|
unsigned int index; \
|
|
|
|
\
|
|
|
|
index = SHOW_UBITS(name, gb, bits); \
|
|
|
|
code = table[index][0]; \
|
|
|
|
n = table[index][1]; \
|
|
|
|
\
|
|
|
|
if (max_depth > 1 && n < 0) { \
|
|
|
|
LAST_SKIP_BITS(name, gb, bits); \
|
|
|
|
UPDATE_CACHE(name, gb); \
|
|
|
|
\
|
|
|
|
nb_bits = -n; \
|
|
|
|
\
|
|
|
|
index = SHOW_UBITS(name, gb, nb_bits) + code; \
|
|
|
|
code = table[index][0]; \
|
|
|
|
n = table[index][1]; \
|
|
|
|
if (max_depth > 2 && n < 0) { \
|
|
|
|
LAST_SKIP_BITS(name, gb, nb_bits); \
|
|
|
|
UPDATE_CACHE(name, gb); \
|
|
|
|
\
|
|
|
|
nb_bits = -n; \
|
|
|
|
\
|
|
|
|
index = SHOW_UBITS(name, gb, nb_bits) + code; \
|
|
|
|
code = table[index][0]; \
|
|
|
|
n = table[index][1]; \
|
|
|
|
} \
|
|
|
|
} \
|
|
|
|
SKIP_BITS(name, gb, n); \
|
|
|
|
} while (0)
|
|
|
|
|
2013-01-20 15:10:24 +00:00
|
|
|
#define GET_RL_VLC(level, run, name, gb, table, bits, \
|
|
|
|
max_depth, need_update) \
|
|
|
|
do { \
|
|
|
|
int n, nb_bits; \
|
|
|
|
unsigned int index; \
|
|
|
|
\
|
|
|
|
index = SHOW_UBITS(name, gb, bits); \
|
|
|
|
level = table[index].level; \
|
|
|
|
n = table[index].len; \
|
|
|
|
\
|
|
|
|
if (max_depth > 1 && n < 0) { \
|
|
|
|
SKIP_BITS(name, gb, bits); \
|
|
|
|
if (need_update) { \
|
|
|
|
UPDATE_CACHE(name, gb); \
|
|
|
|
} \
|
|
|
|
\
|
|
|
|
nb_bits = -n; \
|
|
|
|
\
|
|
|
|
index = SHOW_UBITS(name, gb, nb_bits) + level; \
|
|
|
|
level = table[index].level; \
|
|
|
|
n = table[index].len; \
|
|
|
|
} \
|
|
|
|
run = table[index].run; \
|
|
|
|
SKIP_BITS(name, gb, n); \
|
2011-01-23 01:56:27 +00:00
|
|
|
} while (0)
|
2004-12-29 17:50:25 +00:00
|
|
|
|
|
|
|
/**
|
2011-12-17 01:07:32 +00:00
|
|
|
* Parse a vlc code.
|
2005-12-17 18:14:38 +00:00
|
|
|
* @param bits is the number of bits which will be read at once, must be
|
2004-12-29 17:50:25 +00:00
|
|
|
* identical to nb_bits in init_vlc()
|
2007-04-07 14:09:20 +00:00
|
|
|
* @param max_depth is the number of times bits bits must be read to completely
|
2005-12-17 18:14:38 +00:00
|
|
|
* read the longest vlc code
|
2004-12-29 17:50:25 +00:00
|
|
|
* = (max_vlc_length + bits - 1) / bits
|
|
|
|
*/
|
2006-12-08 00:35:08 +00:00
|
|
|
static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
|
2011-12-17 01:05:35 +00:00
|
|
|
int bits, int max_depth)
|
2004-12-29 17:50:25 +00:00
|
|
|
{
|
|
|
|
int code;
|
2005-12-17 18:14:38 +00:00
|
|
|
|
2011-01-23 01:24:46 +00:00
|
|
|
OPEN_READER(re, s);
|
|
|
|
UPDATE_CACHE(re, s);
|
2004-12-29 17:50:25 +00:00
|
|
|
|
2011-01-23 01:24:46 +00:00
|
|
|
GET_VLC(code, re, s, table, bits, max_depth);
|
2004-12-29 17:50:25 +00:00
|
|
|
|
2011-01-23 01:24:46 +00:00
|
|
|
CLOSE_READER(re, s);
|
2013-01-20 15:10:24 +00:00
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
return code;
|
|
|
|
}
|
|
|
|
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline int decode012(GetBitContext *gb)
|
|
|
|
{
|
2011-01-23 14:01:43 +00:00
|
|
|
int n;
|
|
|
|
n = get_bits1(gb);
|
|
|
|
if (n == 0)
|
|
|
|
return 0;
|
|
|
|
else
|
|
|
|
return get_bits1(gb) + 1;
|
|
|
|
}
|
|
|
|
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline int decode210(GetBitContext *gb)
|
|
|
|
{
|
2011-01-23 14:01:43 +00:00
|
|
|
if (get_bits1(gb))
|
|
|
|
return 0;
|
|
|
|
else
|
|
|
|
return 2 - get_bits1(gb);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int get_bits_left(GetBitContext *gb)
|
|
|
|
{
|
|
|
|
return gb->size_in_bits - get_bits_count(gb);
|
|
|
|
}
|
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
//#define TRACE
|
|
|
|
|
|
|
|
#ifdef TRACE
|
2011-12-17 01:05:35 +00:00
|
|
|
static inline void print_bin(int bits, int n)
|
|
|
|
{
|
2004-12-29 17:50:25 +00:00
|
|
|
int i;
|
2005-12-17 18:14:38 +00:00
|
|
|
|
2013-01-20 15:10:24 +00:00
|
|
|
for (i = n - 1; i >= 0; i--)
|
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%d", (bits >> i) & 1);
|
2011-01-23 01:56:27 +00:00
|
|
|
for (i = n; i < 24; i++)
|
2005-01-19 12:58:34 +00:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, " ");
|
2004-12-29 17:50:25 +00:00
|
|
|
}
|
|
|
|
|
2012-09-25 17:03:59 +00:00
|
|
|
static inline int get_bits_trace(GetBitContext *s, int n, const char *file,
|
2011-12-17 01:05:35 +00:00
|
|
|
const char *func, int line)
|
|
|
|
{
|
2011-01-23 01:56:27 +00:00
|
|
|
int r = get_bits(s, n);
|
2005-12-17 18:14:38 +00:00
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
print_bin(r, n);
|
2011-01-23 01:56:27 +00:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n",
|
2013-01-20 15:10:24 +00:00
|
|
|
r, n, r, get_bits_count(s) - n, file, func, line);
|
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
return r;
|
|
|
|
}
|
2013-01-20 15:10:24 +00:00
|
|
|
|
2011-01-23 01:56:27 +00:00
|
|
|
static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2],
|
2012-09-25 17:03:59 +00:00
|
|
|
int bits, int max_depth, const char *file,
|
2011-12-17 01:05:35 +00:00
|
|
|
const char *func, int line)
|
|
|
|
{
|
2011-01-23 01:56:27 +00:00
|
|
|
int show = show_bits(s, 24);
|
|
|
|
int pos = get_bits_count(s);
|
|
|
|
int r = get_vlc2(s, table, bits, max_depth);
|
|
|
|
int len = get_bits_count(s) - pos;
|
2013-01-20 15:10:24 +00:00
|
|
|
int bits2 = show >> (24 - len);
|
2005-12-17 18:14:38 +00:00
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
print_bin(bits2, len);
|
2005-12-17 18:14:38 +00:00
|
|
|
|
2011-01-23 01:56:27 +00:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n",
|
|
|
|
bits2, len, r, pos, file, func, line);
|
2013-01-20 15:10:24 +00:00
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
return r;
|
|
|
|
}
|
2013-01-20 15:10:24 +00:00
|
|
|
|
2012-09-25 17:03:59 +00:00
|
|
|
static inline int get_xbits_trace(GetBitContext *s, int n, const char *file,
|
2011-12-17 01:05:35 +00:00
|
|
|
const char *func, int line)
|
|
|
|
{
|
2011-01-23 01:56:27 +00:00
|
|
|
int show = show_bits(s, n);
|
|
|
|
int r = get_xbits(s, n);
|
2005-12-17 18:14:38 +00:00
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
print_bin(show, n);
|
2011-01-23 01:56:27 +00:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n",
|
2013-01-20 15:10:24 +00:00
|
|
|
show, n, r, get_bits_count(s) - n, file, func, line);
|
|
|
|
|
2004-12-29 17:50:25 +00:00
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
2013-01-20 15:10:24 +00:00
|
|
|
#define get_bits(s, n) get_bits_trace(s , n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
|
|
#define get_bits1(s) get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
2004-12-29 17:50:25 +00:00
|
|
|
#define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
2013-01-20 15:10:24 +00:00
|
|
|
|
|
|
|
#define get_vlc(s, vlc) get_vlc_trace(s, (vlc)->table, (vlc)->bits, 3, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
|
|
#define get_vlc2(s, tab, bits, max) get_vlc_trace(s, tab, bits, max, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
2004-12-29 17:50:25 +00:00
|
|
|
|
2007-02-27 09:39:04 +00:00
|
|
|
#define tprintf(p, ...) av_log(p, AV_LOG_DEBUG, __VA_ARGS__)
|
2004-12-29 17:50:25 +00:00
|
|
|
|
|
|
|
#else //TRACE
|
2013-01-20 15:10:24 +00:00
|
|
|
#define tprintf(p, ...) { }
|
2004-12-29 17:50:25 +00:00
|
|
|
#endif
|
|
|
|
|
2009-04-13 16:20:26 +00:00
|
|
|
#endif /* AVCODEC_GET_BITS_H */
|