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-rw-r--r--libfaad2/bits.h260
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diff --git a/libfaad2/bits.h b/libfaad2/bits.h
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+++ b/libfaad2/bits.h
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+/*
+** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
+** Copyright (C) 2003 M. Bakker, Ahead Software AG, http://www.nero.com
+**
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+** GNU General Public License for more details.
+**
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**
+** Any non-GPL usage of this software or parts of this software is strictly
+** forbidden.
+**
+** Commercial non-GPL licensing of this software is possible.
+** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
+**
+** $Id$
+**/
+
+#ifndef __BITS_H__
+#define __BITS_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "analysis.h"
+#ifdef ANALYSIS
+#include <stdio.h>
+#endif
+
+#define BYTE_NUMBIT 8
+#define bit2byte(a) ((a+7)/BYTE_NUMBIT)
+
+typedef struct _bitfile
+{
+ /* bit input */
+ uint32_t bufa;
+ uint32_t bufb;
+ uint32_t bits_left;
+ uint32_t buffer_size; /* size of the buffer in bytes */
+ uint32_t bytes_used;
+ uint8_t no_more_reading;
+ uint8_t error;
+ uint32_t *tail;
+ uint32_t *start;
+ void *buffer;
+} bitfile;
+
+
+#if defined (_WIN32) && !defined(_WIN32_WCE)
+#define BSWAP(a) __asm mov eax,a __asm bswap eax __asm mov a, eax
+#elif defined(LINUX) || defined(DJGPP)
+#define BSWAP(a) __asm__ ( "bswapl %0\n" : "=r" (a) : "0" (a) )
+#else
+#define BSWAP(a) \
+ ((a) = ( ((a)&0xff)<<24) | (((a)&0xff00)<<8) | (((a)>>8)&0xff00) | (((a)>>24)&0xff))
+#endif
+
+static uint32_t bitmask[] = {
+ 0x0, 0x1, 0x3, 0x7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF,
+ 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF,
+ 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF,
+ 0x7FFFFF, 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF, 0x7FFFFFF,
+ 0xFFFFFFF, 0x1FFFFFFF, 0x3FFFFFFF, 0x7FFFFFFF
+};
+
+void faad_initbits(bitfile *ld, void *buffer, uint32_t buffer_size);
+void faad_endbits(bitfile *ld);
+void faad_initbits_rev(bitfile *ld, void *buffer,
+ uint32_t bits_in_buffer);
+uint8_t faad_byte_align(bitfile *ld);
+uint32_t faad_get_processed_bits(bitfile *ld);
+void faad_rewindbits(bitfile *ld);
+uint8_t *faad_getbitbuffer(bitfile *ld, uint32_t bits
+ DEBUGDEC);
+
+/* circumvent memory alignment errors on ARM */
+static INLINE uint32_t getdword(void *mem)
+{
+#ifdef ARM
+ uint32_t tmp;
+ ((uint8_t*)&tmp)[0] = ((uint8_t*)mem)[0];
+ ((uint8_t*)&tmp)[1] = ((uint8_t*)mem)[1];
+ ((uint8_t*)&tmp)[2] = ((uint8_t*)mem)[2];
+ ((uint8_t*)&tmp)[3] = ((uint8_t*)mem)[3];
+
+ return tmp;
+#else
+ return *(uint32_t*)mem;
+#endif
+}
+
+static INLINE uint32_t faad_showbits(bitfile *ld, uint32_t bits)
+{
+ if (bits <= ld->bits_left)
+ {
+ return (ld->bufa >> (ld->bits_left - bits)) & bitmask[bits];
+ } else {
+ bits -= ld->bits_left;
+ return ((ld->bufa & bitmask[ld->bits_left]) << bits) | (ld->bufb >> (32 - bits));
+ }
+}
+
+static INLINE void faad_flushbits(bitfile *ld, uint32_t bits)
+{
+ /* do nothing if error */
+ if (ld->error != 0)
+ return;
+
+ if (bits < ld->bits_left)
+ {
+ ld->bits_left -= bits;
+ } else {
+ uint32_t tmp;
+
+ ld->bufa = ld->bufb;
+ tmp = getdword(ld->tail);
+ ld->tail++;
+#ifndef ARCH_IS_BIG_ENDIAN
+ BSWAP(tmp);
+#endif
+ ld->bufb = tmp;
+ ld->bits_left += (32 - bits);
+ ld->bytes_used += 4;
+ if (ld->bytes_used == ld->buffer_size)
+ ld->no_more_reading = 1;
+ if (ld->bytes_used > ld->buffer_size)
+ ld->error = 1;
+ }
+}
+
+/* return next n bits (right adjusted) */
+static INLINE uint32_t faad_getbits(bitfile *ld, uint32_t n DEBUGDEC)
+{
+ uint32_t ret;
+
+ if (ld->no_more_reading)
+ return 0;
+
+ if (n == 0)
+ return 0;
+
+ ret = faad_showbits(ld, n);
+ faad_flushbits(ld, n);
+
+#ifdef ANALYSIS
+ if (print)
+ fprintf(stdout, "%4d %2d bits, val: %4d, variable: %d %s\n", dbg_count++, n, ret, var, dbg);
+#endif
+
+ return ret;
+}
+
+static INLINE uint8_t faad_get1bit(bitfile *ld DEBUGDEC)
+{
+ uint8_t r;
+
+ if (ld->bits_left == 0)
+ return (uint8_t)faad_getbits(ld, 1 DEBUGVAR(print,var,dbg));
+
+ ld->bits_left--;
+ r = (uint8_t)((ld->bufa >> ld->bits_left) & 1);
+
+ return r;
+}
+
+/* reversed bitreading routines */
+static INLINE uint32_t faad_showbits_rev(bitfile *ld, uint32_t bits)
+{
+ uint8_t i;
+ uint32_t B = 0;
+
+ if (bits <= ld->bits_left)
+ {
+ for (i = 0; i < bits; i++)
+ {
+ if (ld->bufa & (1 << (i + (32 - ld->bits_left))))
+ B |= (1 << (bits - i - 1));
+ }
+ return B;
+ } else {
+ for (i = 0; i < ld->bits_left; i++)
+ {
+ if (ld->bufa & (1 << (i + (32 - ld->bits_left))))
+ B |= (1 << (bits - i - 1));
+ }
+ for (i = 0; i < bits - ld->bits_left; i++)
+ {
+ if (ld->bufb & (1 << (i + (32-ld->bits_left))))
+ B |= (1 << (bits - ld->bits_left - i - 1));
+ }
+ return B;
+ }
+}
+
+static INLINE void faad_flushbits_rev(bitfile *ld, uint32_t bits)
+{
+ /* do nothing if error */
+ if (ld->error != 0)
+ return;
+
+ if (bits < ld->bits_left)
+ {
+ ld->bits_left -= bits;
+ } else {
+ uint32_t tmp;
+
+ ld->bufa = ld->bufb;
+ tmp = getdword(ld->start);
+#ifndef ARCH_IS_BIG_ENDIAN
+ BSWAP(tmp);
+#endif
+ ld->bufb = tmp;
+ ld->start--;
+ ld->bits_left += (32 - bits);
+
+ ld->bytes_used += 4;
+ if (ld->bytes_used == ld->buffer_size)
+ ld->no_more_reading = 1;
+ if (ld->bytes_used > ld->buffer_size)
+ ld->error = 1;
+ }
+}
+
+static INLINE uint32_t faad_getbits_rev(bitfile *ld, uint32_t n
+ DEBUGDEC)
+{
+ uint32_t ret;
+
+ if (ld->no_more_reading)
+ return 0;
+
+ if (n == 0)
+ return 0;
+
+ ret = faad_showbits_rev(ld, n);
+ faad_flushbits_rev(ld, n);
+
+#ifdef ANALYSIS
+ if (print)
+ fprintf(stdout, "%4d %2d bits, val: %4d, variable: %d %s\n", dbg_count++, n, ret, var, dbg);
+#endif
+
+ return ret;
+}
+
+
+#ifdef __cplusplus
+}
+#endif
+#endif
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