2006-09-10 16:02:42 +02:00
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/*
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* copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
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*
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2006-10-07 17:30:46 +02:00
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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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2006-09-10 16:02:42 +02:00
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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 17:30:46 +02:00
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* version 2.1 of the License, or (at your option) any later version.
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2006-09-10 16:02:42 +02:00
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*
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2006-10-07 17:30:46 +02:00
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* FFmpeg is distributed in the hope that it will be useful,
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2006-09-10 16:02:42 +02:00
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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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2006-10-07 17:30:46 +02:00
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* License along with FFmpeg; if not, write to the Free Software
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2006-09-10 16:02:42 +02:00
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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 18:50:25 +01:00
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/**
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2010-04-20 16:45:34 +02:00
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* @file
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2009-04-13 18:20:26 +02:00
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* bitstream reader API header.
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2004-12-29 18:50:25 +01:00
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*/
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2009-04-13 18:20:26 +02:00
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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 18:50:25 +01:00
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2007-06-17 00:59:13 +02:00
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#include <stdint.h>
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#include <stdlib.h>
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#include <assert.h>
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2008-05-09 13:56:36 +02:00
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#include "libavutil/bswap.h"
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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 03:00:47 +01:00
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#include "mathops.h"
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2006-08-28 20:44:49 +02:00
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2006-08-28 20:46:01 +02:00
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#if defined(ALT_BITSTREAM_READER_LE) && !defined(ALT_BITSTREAM_READER)
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2007-08-04 14:21:00 +02:00
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# define ALT_BITSTREAM_READER
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2006-08-28 20:46:01 +02:00
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#endif
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2011-01-23 02:18:13 +01:00
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#if !defined(A32_BITSTREAM_READER) && !defined(ALT_BITSTREAM_READER)
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2009-12-22 09:09:46 +01:00
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# if ARCH_ARM && !HAVE_FAST_UNALIGNED
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2006-08-29 00:25:30 +02:00
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# define A32_BITSTREAM_READER
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# else
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2007-08-04 14:21:00 +02:00
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# define ALT_BITSTREAM_READER
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2004-12-29 18:50:25 +01:00
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//#define A32_BITSTREAM_READER
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2006-08-29 00:25:30 +02:00
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# endif
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2006-08-26 11:34:02 +02:00
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#endif
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2005-12-17 19:14:38 +01:00
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2004-12-29 18:50:25 +01:00
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/* bit input */
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/* buffer, buffer_end and size_in_bits must be present and used by every reader */
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typedef struct GetBitContext {
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const uint8_t *buffer, *buffer_end;
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#ifdef ALT_BITSTREAM_READER
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int index;
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#elif defined A32_BITSTREAM_READER
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uint32_t *buffer_ptr;
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uint32_t cache0;
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uint32_t cache1;
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int bit_count;
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#endif
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int size_in_bits;
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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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name
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2008-08-29 20:43:20 +02:00
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arbitrary name which is used as prefix for the internal variables
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2004-12-29 18:50:25 +01:00
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gb
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getbitcontext
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OPEN_READER(name, gb)
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loads gb into local variables
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CLOSE_READER(name, gb)
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stores local vars in gb
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UPDATE_CACHE(name, gb)
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refills 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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GET_CACHE(name, gb)
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will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit)
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SHOW_UBITS(name, gb, num)
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2005-06-17 17:02:53 +02:00
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will return the next num bits
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2004-12-29 18:50:25 +01:00
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SHOW_SBITS(name, gb, num)
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2005-06-17 17:02:53 +02:00
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will return the next num bits and do sign extension
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2004-12-29 18:50:25 +01:00
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SKIP_BITS(name, gb, num)
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will skip over the next num bits
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2005-06-17 17:02:53 +02:00
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note, this is equivalent to SKIP_CACHE; SKIP_COUNTER
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2004-12-29 18:50:25 +01:00
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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 MUST be called before UPDATE_CACHE / CLOSE_READER)
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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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LAST_SKIP_CACHE(name, gb, num)
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will remove the next num bits from the cache if it is needed for UPDATE_CACHE otherwise it will do nothing
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LAST_SKIP_BITS(name, gb, num)
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2009-09-11 08:20:05 +02:00
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is equivalent to LAST_SKIP_CACHE; SKIP_COUNTER
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2004-12-29 18:50:25 +01:00
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for examples see get_bits, show_bits, skip_bits, get_vlc
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*/
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#ifdef ALT_BITSTREAM_READER
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# define MIN_CACHE_BITS 25
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2011-01-23 02:56:27 +01:00
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# define OPEN_READER(name, gb) \
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unsigned int name##_index = (gb)->index; \
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2011-05-05 03:09:48 +02:00
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av_unused unsigned int name##_cache
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define CLOSE_READER(name, gb) (gb)->index = name##_index
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2004-12-29 18:50:25 +01:00
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2005-05-11 03:46:13 +02:00
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# ifdef ALT_BITSTREAM_READER_LE
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2011-01-23 02:56:27 +01:00
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# define UPDATE_CACHE(name, gb) \
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name##_cache = AV_RL32(((const uint8_t *)(gb)->buffer)+(name##_index>>3)) >> (name##_index&0x07)
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2005-05-11 03:46:13 +02:00
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2011-01-23 02:56:27 +01:00
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# define SKIP_CACHE(name, gb, num) name##_cache >>= (num)
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2005-05-11 03:46:13 +02:00
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# else
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2011-01-23 02:56:27 +01:00
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# define UPDATE_CACHE(name, gb) \
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name##_cache = AV_RB32(((const uint8_t *)(gb)->buffer)+(name##_index>>3)) << (name##_index&0x07)
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define SKIP_CACHE(name, gb, num) name##_cache <<= (num)
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2005-05-11 03:46:13 +02:00
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# endif
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2004-12-29 18:50:25 +01:00
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// FIXME name?
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2011-01-23 02:56:27 +01:00
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# define SKIP_COUNTER(name, gb, num) name##_index += (num)
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define SKIP_BITS(name, gb, num) do { \
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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 18:50:25 +01:00
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# define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
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2011-01-23 02:24:46 +01:00
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# define LAST_SKIP_CACHE(name, gb, num)
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2004-12-29 18:50:25 +01:00
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2005-05-11 03:46:13 +02:00
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# ifdef ALT_BITSTREAM_READER_LE
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2011-01-23 02:56:27 +01:00
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# define SHOW_UBITS(name, gb, num) zero_extend(name##_cache, num)
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2006-10-12 13:54:24 +02:00
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2011-01-23 02:56:27 +01:00
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# define SHOW_SBITS(name, gb, num) sign_extend(name##_cache, num)
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2005-05-11 03:46:13 +02:00
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# else
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2011-01-23 02:56:27 +01:00
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# define SHOW_UBITS(name, gb, num) NEG_USR32(name##_cache, num)
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define SHOW_SBITS(name, gb, num) NEG_SSR32(name##_cache, num)
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2006-10-12 13:54:24 +02:00
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# endif
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define GET_CACHE(name, gb) ((uint32_t)name##_cache)
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2004-12-29 18:50:25 +01:00
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2010-01-24 17:22:09 +01:00
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static inline int get_bits_count(const GetBitContext *s){
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2004-12-29 18:50:25 +01:00
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return s->index;
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}
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2006-08-26 12:26:14 +02:00
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static inline void skip_bits_long(GetBitContext *s, int n){
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2006-08-26 13:50:23 +02:00
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s->index += n;
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2006-08-26 12:26:14 +02:00
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}
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2004-12-29 18:50:25 +01:00
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#elif defined A32_BITSTREAM_READER
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# define MIN_CACHE_BITS 32
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2011-01-23 02:56:27 +01:00
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# define OPEN_READER(name, gb) \
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int name##_bit_count = (gb)->bit_count; \
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uint32_t name##_cache0 = (gb)->cache0; \
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uint32_t name##_cache1 = (gb)->cache1; \
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uint32_t *name##_buffer_ptr = (gb)->buffer_ptr
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# define CLOSE_READER(name, gb) do { \
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(gb)->bit_count = name##_bit_count; \
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(gb)->cache0 = name##_cache0; \
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(gb)->cache1 = name##_cache1; \
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(gb)->buffer_ptr = name##_buffer_ptr; \
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2011-01-23 02:24:46 +01:00
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} while (0)
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define UPDATE_CACHE(name, gb) do { \
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if(name##_bit_count > 0){ \
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const uint32_t next = av_be2ne32(*name##_buffer_ptr); \
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name##_cache0 |= NEG_USR32(next, name##_bit_count); \
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name##_cache1 |= next << name##_bit_count; \
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name##_buffer_ptr++; \
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name##_bit_count -= 32; \
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} \
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} while (0)
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2004-12-29 18:50:25 +01:00
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2009-01-14 00:44:16 +01:00
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#if ARCH_X86
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2011-01-23 02:56:27 +01:00
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# define SKIP_CACHE(name, gb, num) \
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__asm__("shldl %2, %1, %0 \n\t" \
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"shll %2, %1 \n\t" \
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: "+r" (name##_cache0), "+r" (name##_cache1) \
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: "Ic" ((uint8_t)(num)))
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2004-12-29 18:50:25 +01:00
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#else
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2011-01-23 02:56:27 +01:00
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# define SKIP_CACHE(name, gb, num) do { \
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name##_cache0 <<= (num); \
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name##_cache0 |= NEG_USR32(name##_cache1,num); \
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name##_cache1 <<= (num); \
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2011-01-23 02:24:46 +01:00
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} while (0)
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2004-12-29 18:50:25 +01:00
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#endif
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2011-01-23 02:56:27 +01:00
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# define SKIP_COUNTER(name, gb, num) name##_bit_count += (num)
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define SKIP_BITS(name, gb, num) do { \
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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 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
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2004-12-29 18:50:25 +01:00
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# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
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2011-01-23 02:56:27 +01:00
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# define SHOW_UBITS(name, gb, num) NEG_USR32(name##_cache0, num)
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define SHOW_SBITS(name, gb, num) NEG_SSR32(name##_cache0, num)
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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# define GET_CACHE(name, gb) name##_cache0
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2004-12-29 18:50:25 +01:00
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2011-01-23 02:56:27 +01:00
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static inline int get_bits_count(const GetBitContext *s) {
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2004-12-29 18:50:25 +01:00
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return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count;
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}
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2006-08-26 12:26:14 +02:00
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static inline void skip_bits_long(GetBitContext *s, int n){
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2011-01-23 02:24:46 +01:00
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OPEN_READER(re, s);
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2006-08-26 12:26:14 +02:00
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re_bit_count += n;
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2006-08-26 13:26:54 +02:00
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re_buffer_ptr += re_bit_count>>5;
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2006-08-26 12:26:14 +02:00
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re_bit_count &= 31;
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2011-01-23 02:56:27 +01:00
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re_cache0 = av_be2ne32(re_buffer_ptr[-1]) << re_bit_count;
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2006-08-26 13:06:33 +02:00
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re_cache1 = 0;
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2011-01-23 02:24:46 +01:00
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UPDATE_CACHE(re, s);
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CLOSE_READER(re, s);
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2006-08-26 12:26:14 +02:00
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}
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2004-12-29 18:50:25 +01:00
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#endif
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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 19:14:38 +01:00
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* if MSB not set it is negative
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2004-12-29 18:50:25 +01:00
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* @param n length in bits
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2005-12-17 19:14:38 +01:00
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* @author BERO
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2004-12-29 18:50:25 +01:00
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*/
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static inline int get_xbits(GetBitContext *s, int n){
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2006-03-31 22:40:22 +02:00
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register int sign;
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2004-12-29 18:50:25 +01:00
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register int32_t cache;
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2011-01-23 02:24:46 +01:00
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OPEN_READER(re, s);
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UPDATE_CACHE(re, s);
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2011-01-23 02:56:27 +01:00
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cache = GET_CACHE(re, s);
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sign = ~cache >> 31;
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2011-01-23 02:24:46 +01:00
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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 22:40:22 +02:00
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return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
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2004-12-29 18:50:25 +01:00
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}
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|
|
static inline int get_sbits(GetBitContext *s, int n){
|
|
|
|
register int tmp;
|
2011-01-23 02:24:46 +01:00
|
|
|
OPEN_READER(re, s);
|
|
|
|
UPDATE_CACHE(re, s);
|
2011-01-23 02:56:27 +01:00
|
|
|
tmp = SHOW_SBITS(re, s, n);
|
2011-01-23 02:24:46 +01:00
|
|
|
LAST_SKIP_BITS(re, s, n);
|
|
|
|
CLOSE_READER(re, s);
|
2004-12-29 18:50:25 +01:00
|
|
|
return tmp;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2011-01-23 02:18:13 +01:00
|
|
|
* Read 1-25 bits.
|
2004-12-29 18:50:25 +01:00
|
|
|
*/
|
|
|
|
static inline unsigned int get_bits(GetBitContext *s, int n){
|
|
|
|
register int tmp;
|
2011-01-23 02:24:46 +01:00
|
|
|
OPEN_READER(re, s);
|
|
|
|
UPDATE_CACHE(re, s);
|
2011-01-23 02:56:27 +01:00
|
|
|
tmp = SHOW_UBITS(re, s, n);
|
2011-01-23 02:24:46 +01:00
|
|
|
LAST_SKIP_BITS(re, s, n);
|
|
|
|
CLOSE_READER(re, s);
|
2004-12-29 18:50:25 +01:00
|
|
|
return tmp;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2011-01-23 02:18:13 +01:00
|
|
|
* Shows 1-25 bits.
|
2004-12-29 18:50:25 +01:00
|
|
|
*/
|
|
|
|
static inline unsigned int show_bits(GetBitContext *s, int n){
|
|
|
|
register int tmp;
|
2011-01-23 02:24:46 +01:00
|
|
|
OPEN_READER(re, s);
|
|
|
|
UPDATE_CACHE(re, s);
|
2011-01-23 02:56:27 +01:00
|
|
|
tmp = SHOW_UBITS(re, s, n);
|
2004-12-29 18:50:25 +01:00
|
|
|
return tmp;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void skip_bits(GetBitContext *s, int n){
|
|
|
|
//Note gcc seems to optimize this to s->index+=n for the ALT_READER :))
|
2011-01-23 02:24:46 +01:00
|
|
|
OPEN_READER(re, s);
|
|
|
|
UPDATE_CACHE(re, s);
|
|
|
|
LAST_SKIP_BITS(re, s, n);
|
|
|
|
CLOSE_READER(re, s);
|
2004-12-29 18:50:25 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned int get_bits1(GetBitContext *s){
|
|
|
|
#ifdef ALT_BITSTREAM_READER
|
2011-01-23 02:56:27 +01:00
|
|
|
unsigned int index = s->index;
|
|
|
|
uint8_t result = s->buffer[index>>3];
|
2005-05-11 03:46:13 +02:00
|
|
|
#ifdef ALT_BITSTREAM_READER_LE
|
2011-01-23 02:56:27 +01:00
|
|
|
result >>= index & 7;
|
|
|
|
result &= 1;
|
2005-05-11 03:46:13 +02:00
|
|
|
#else
|
2011-01-23 02:56:27 +01:00
|
|
|
result <<= index & 7;
|
|
|
|
result >>= 8 - 1;
|
2005-05-11 03:46:13 +02:00
|
|
|
#endif
|
2004-12-29 18:50:25 +01:00
|
|
|
index++;
|
2011-01-23 02:56:27 +01:00
|
|
|
s->index = index;
|
2004-12-29 18:50:25 +01:00
|
|
|
|
|
|
|
return result;
|
|
|
|
#else
|
|
|
|
return get_bits(s, 1);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned int show_bits1(GetBitContext *s){
|
|
|
|
return show_bits(s, 1);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void skip_bits1(GetBitContext *s){
|
|
|
|
skip_bits(s, 1);
|
|
|
|
}
|
|
|
|
|
2006-08-28 20:44:49 +02:00
|
|
|
/**
|
|
|
|
* reads 0-32 bits.
|
|
|
|
*/
|
|
|
|
static inline unsigned int get_bits_long(GetBitContext *s, int n){
|
2011-01-23 02:56:27 +01:00
|
|
|
if (n <= MIN_CACHE_BITS) return get_bits(s, n);
|
|
|
|
else {
|
2006-09-26 00:47:55 +02:00
|
|
|
#ifdef ALT_BITSTREAM_READER_LE
|
2011-01-23 02:56:27 +01:00
|
|
|
int ret = get_bits(s, 16);
|
2006-09-26 00:47:55 +02:00
|
|
|
return ret | (get_bits(s, n-16) << 16);
|
|
|
|
#else
|
2011-01-23 02:56:27 +01:00
|
|
|
int ret = get_bits(s, 16) << (n-16);
|
2006-08-28 20:44:49 +02:00
|
|
|
return ret | get_bits(s, n-16);
|
2006-09-26 00:47:55 +02:00
|
|
|
#endif
|
2006-08-28 20:44:49 +02:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2009-03-03 03:00:47 +01:00
|
|
|
/**
|
|
|
|
* reads 0-32 bits as a signed integer.
|
|
|
|
*/
|
|
|
|
static inline int get_sbits_long(GetBitContext *s, int n) {
|
|
|
|
return sign_extend(get_bits_long(s, n), n);
|
|
|
|
}
|
|
|
|
|
2006-08-28 20:44:49 +02:00
|
|
|
/**
|
|
|
|
* shows 0-32 bits.
|
|
|
|
*/
|
|
|
|
static inline unsigned int show_bits_long(GetBitContext *s, int n){
|
2011-01-23 02:56:27 +01:00
|
|
|
if (n <= MIN_CACHE_BITS) return show_bits(s, n);
|
|
|
|
else {
|
|
|
|
GetBitContext gb = *s;
|
2009-03-02 20:42:31 +01:00
|
|
|
return get_bits_long(&gb, n);
|
2006-08-28 20:44:49 +02:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int check_marker(GetBitContext *s, const char *msg)
|
|
|
|
{
|
2011-01-23 02:56:27 +01:00
|
|
|
int bit = get_bits1(s);
|
|
|
|
if (!bit)
|
2006-08-28 20:44:49 +02:00
|
|
|
av_log(NULL, AV_LOG_INFO, "Marker bit missing %s\n", msg);
|
|
|
|
|
|
|
|
return bit;
|
|
|
|
}
|
|
|
|
|
2004-12-29 18:50:25 +01:00
|
|
|
/**
|
|
|
|
* init GetBitContext.
|
|
|
|
* @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes larger then the actual read bits
|
|
|
|
* because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
|
|
|
|
* @param bit_size the size of the buffer in bits
|
2009-09-08 10:30:56 +02:00
|
|
|
*
|
|
|
|
* While GetBitContext stores the buffer size, for performance reasons you are
|
|
|
|
* responsible for checking for the buffer end yourself (take advantage of the padding)!
|
2004-12-29 18:50:25 +01:00
|
|
|
*/
|
|
|
|
static inline void init_get_bits(GetBitContext *s,
|
|
|
|
const uint8_t *buffer, int bit_size)
|
|
|
|
{
|
2011-01-23 02:56:27 +01:00
|
|
|
int buffer_size = (bit_size+7)>>3;
|
|
|
|
if (buffer_size < 0 || bit_size < 0) {
|
2005-09-22 01:18:52 +02:00
|
|
|
buffer_size = bit_size = 0;
|
|
|
|
buffer = NULL;
|
|
|
|
}
|
2004-12-29 18:50:25 +01:00
|
|
|
|
2011-01-23 02:56:27 +01:00
|
|
|
s->buffer = buffer;
|
|
|
|
s->size_in_bits = bit_size;
|
|
|
|
s->buffer_end = buffer + buffer_size;
|
2004-12-29 18:50:25 +01:00
|
|
|
#ifdef ALT_BITSTREAM_READER
|
2011-01-23 02:56:27 +01:00
|
|
|
s->index = 0;
|
2006-08-26 13:37:33 +02:00
|
|
|
#elif defined A32_BITSTREAM_READER
|
2011-01-23 02:56:27 +01:00
|
|
|
s->buffer_ptr = (uint32_t*)((intptr_t)buffer & ~3);
|
|
|
|
s->bit_count = 32 + 8*((intptr_t)buffer & 3);
|
2006-08-26 13:37:33 +02:00
|
|
|
skip_bits_long(s, 0);
|
2004-12-29 18:50:25 +01:00
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
2006-09-04 19:25:38 +02:00
|
|
|
static inline void align_get_bits(GetBitContext *s)
|
2006-08-26 12:26:14 +02:00
|
|
|
{
|
2011-01-23 02:56:27 +01:00
|
|
|
int n = -get_bits_count(s) & 7;
|
|
|
|
if (n) skip_bits(s, n);
|
2006-08-26 12:26:14 +02:00
|
|
|
}
|
|
|
|
|
2011-01-23 02:56:27 +01:00
|
|
|
#define init_vlc(vlc, nb_bits, nb_codes, \
|
|
|
|
bits, bits_wrap, bits_size, \
|
|
|
|
codes, codes_wrap, codes_size, \
|
|
|
|
flags) \
|
|
|
|
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 19:38:56 +02:00
|
|
|
|
|
|
|
int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes,
|
2004-12-29 18:50:25 +01:00
|
|
|
const void *bits, int bits_wrap, int bits_size,
|
|
|
|
const void *codes, int codes_wrap, int codes_size,
|
2007-05-24 19:38:56 +02:00
|
|
|
const void *symbols, int symbols_wrap, int symbols_size,
|
2005-05-11 03:46:13 +02:00
|
|
|
int flags);
|
|
|
|
#define INIT_VLC_LE 2
|
2008-05-30 21:48:02 +02:00
|
|
|
#define INIT_VLC_USE_NEW_STATIC 4
|
2004-12-29 18:50:25 +01:00
|
|
|
void free_vlc(VLC *vlc);
|
|
|
|
|
2011-01-23 02:56:27 +01:00
|
|
|
#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 22:00:19 +02:00
|
|
|
|
|
|
|
|
2004-12-29 18:50:25 +01:00
|
|
|
/**
|
|
|
|
*
|
2010-02-17 22:20:43 +01:00
|
|
|
* 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 18:50:25 +01:00
|
|
|
*/
|
2011-01-23 02:56:27 +01:00
|
|
|
#define GET_VLC(code, name, gb, table, bits, max_depth) do { \
|
|
|
|
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)
|
|
|
|
|
|
|
|
#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); \
|
|
|
|
} while (0)
|
2004-12-29 18:50:25 +01:00
|
|
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
* parses a vlc code, faster then get_vlc()
|
2005-12-17 19:14:38 +01:00
|
|
|
* @param bits is the number of bits which will be read at once, must be
|
2004-12-29 18:50:25 +01:00
|
|
|
* identical to nb_bits in init_vlc()
|
2007-04-07 16:09:20 +02:00
|
|
|
* @param max_depth is the number of times bits bits must be read to completely
|
2005-12-17 19:14:38 +01:00
|
|
|
* read the longest vlc code
|
2004-12-29 18:50:25 +01:00
|
|
|
* = (max_vlc_length + bits - 1) / bits
|
|
|
|
*/
|
2006-12-08 01:35:08 +01:00
|
|
|
static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
|
2004-12-29 18:50:25 +01:00
|
|
|
int bits, int max_depth)
|
|
|
|
{
|
|
|
|
int code;
|
2005-12-17 19:14:38 +01:00
|
|
|
|
2011-01-23 02:24:46 +01:00
|
|
|
OPEN_READER(re, s);
|
|
|
|
UPDATE_CACHE(re, s);
|
2004-12-29 18:50:25 +01:00
|
|
|
|
2011-01-23 02:24:46 +01:00
|
|
|
GET_VLC(code, re, s, table, bits, max_depth);
|
2004-12-29 18:50:25 +01:00
|
|
|
|
2011-01-23 02:24:46 +01:00
|
|
|
CLOSE_READER(re, s);
|
2004-12-29 18:50:25 +01:00
|
|
|
return code;
|
|
|
|
}
|
|
|
|
|
2011-01-23 15:01:43 +01:00
|
|
|
static inline int decode012(GetBitContext *gb){
|
|
|
|
int n;
|
|
|
|
n = get_bits1(gb);
|
|
|
|
if (n == 0)
|
|
|
|
return 0;
|
|
|
|
else
|
|
|
|
return get_bits1(gb) + 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int decode210(GetBitContext *gb){
|
|
|
|
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 18:50:25 +01:00
|
|
|
//#define TRACE
|
|
|
|
|
|
|
|
#ifdef TRACE
|
|
|
|
static inline void print_bin(int bits, int n){
|
|
|
|
int i;
|
2005-12-17 19:14:38 +01:00
|
|
|
|
2011-01-23 02:56:27 +01:00
|
|
|
for (i = n-1; i >= 0; i--) {
|
2005-01-19 13:58:34 +01:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1);
|
2004-12-29 18:50:25 +01:00
|
|
|
}
|
2011-01-23 02:56:27 +01:00
|
|
|
for (i = n; i < 24; i++)
|
2005-01-19 13:58:34 +01:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, " ");
|
2004-12-29 18:50:25 +01:00
|
|
|
}
|
|
|
|
|
2011-01-23 02:56:27 +01:00
|
|
|
static inline int get_bits_trace(GetBitContext *s, int n, char *file,
|
|
|
|
const char *func, int line){
|
|
|
|
int r = get_bits(s, n);
|
2005-12-17 19:14:38 +01:00
|
|
|
|
2004-12-29 18:50:25 +01:00
|
|
|
print_bin(r, n);
|
2011-01-23 02:56:27 +01:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n",
|
|
|
|
r, n, r, get_bits_count(s)-n, file, func, line);
|
2004-12-29 18:50:25 +01:00
|
|
|
return r;
|
|
|
|
}
|
2011-01-23 02:56:27 +01:00
|
|
|
static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2],
|
|
|
|
int bits, int max_depth, char *file,
|
|
|
|
const char *func, int line){
|
|
|
|
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;
|
|
|
|
int bits2 = show >> (24-len);
|
2005-12-17 19:14:38 +01:00
|
|
|
|
2004-12-29 18:50:25 +01:00
|
|
|
print_bin(bits2, len);
|
2005-12-17 19:14:38 +01:00
|
|
|
|
2011-01-23 02:56:27 +01:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n",
|
|
|
|
bits2, len, r, pos, file, func, line);
|
2004-12-29 18:50:25 +01:00
|
|
|
return r;
|
|
|
|
}
|
2011-01-23 02:56:27 +01:00
|
|
|
static inline int get_xbits_trace(GetBitContext *s, int n, char *file,
|
|
|
|
const char *func, int line){
|
|
|
|
int show = show_bits(s, n);
|
|
|
|
int r = get_xbits(s, n);
|
2005-12-17 19:14:38 +01:00
|
|
|
|
2004-12-29 18:50:25 +01:00
|
|
|
print_bin(show, n);
|
2011-01-23 02:56:27 +01:00
|
|
|
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n",
|
|
|
|
show, n, r, get_bits_count(s)-n, file, func, line);
|
2004-12-29 18:50:25 +01:00
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
|
|
|
#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__)
|
|
|
|
#define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
|
|
|
|
#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__)
|
|
|
|
|
2007-02-27 10:39:04 +01:00
|
|
|
#define tprintf(p, ...) av_log(p, AV_LOG_DEBUG, __VA_ARGS__)
|
2004-12-29 18:50:25 +01:00
|
|
|
|
|
|
|
#else //TRACE
|
2007-02-27 10:39:04 +01:00
|
|
|
#define tprintf(p, ...) {}
|
2004-12-29 18:50:25 +01:00
|
|
|
#endif
|
|
|
|
|
2009-04-13 18:20:26 +02:00
|
|
|
#endif /* AVCODEC_GET_BITS_H */
|