ref: a2c4357825c73ef93133df2152be0d6bb6ad8343
dir: /libfaad/bits.h/
/* ** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding ** Copyright (C) 2003-2005 M. Bakker, Nero 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. ** ** The "appropriate copyright message" mentioned in section 2c of the GPLv2 ** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com" ** ** Commercial non-GPL licensing of this software is possible. ** For more info contact Nero AG through Mpeg4AAClicense@nero.com. ** ** $Id: bits.h,v 1.45 2007/11/01 12:33:29 menno Exp $ **/ #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 BYTE_NUMBIT_LD 3 //#define bit2byte(a) ((a+7)/BYTE_NUMBIT) #define bit2byte(a) ((a+7)>>BYTE_NUMBIT_LD) 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_left; uint8_t error; uint32_t *tail; uint32_t *start; const void *buffer; } bitfile; #if 0 static uint32_t const 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 /* added bitmask 32, correct?!?!?! */ , 0xFFFFFFFF }; #endif void faad_initbits(bitfile *ld, const void *buffer, const 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_flushbits_ex(bitfile *ld, uint32_t bits); void faad_rewindbits(bitfile *ld); void faad_resetbits(bitfile *ld, int bits); uint8_t *faad_getbitbuffer(bitfile *ld, uint32_t bits DEBUGDEC); #ifdef DRM void *faad_origbitbuffer(bitfile *ld); uint32_t faad_origbitbuffer_size(bitfile *ld); #endif /* circumvent memory alignment errors on ARM */ static INLINE uint32_t getdword(void *mem) { uint32_t tmp; #ifndef ARCH_IS_BIG_ENDIAN ((uint8_t*)&tmp)[0] = ((uint8_t*)mem)[3]; ((uint8_t*)&tmp)[1] = ((uint8_t*)mem)[2]; ((uint8_t*)&tmp)[2] = ((uint8_t*)mem)[1]; ((uint8_t*)&tmp)[3] = ((uint8_t*)mem)[0]; #else ((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]; #endif return tmp; } /* reads only n bytes from the stream instead of the standard 4 */ static /*INLINE*/ uint32_t getdword_n(void *mem, int n) { uint32_t tmp = 0; #ifndef ARCH_IS_BIG_ENDIAN switch (n) { case 3: ((uint8_t*)&tmp)[1] = ((uint8_t*)mem)[2]; case 2: ((uint8_t*)&tmp)[2] = ((uint8_t*)mem)[1]; case 1: ((uint8_t*)&tmp)[3] = ((uint8_t*)mem)[0]; default: break; } #else switch (n) { case 3: ((uint8_t*)&tmp)[2] = ((uint8_t*)mem)[2]; case 2: ((uint8_t*)&tmp)[1] = ((uint8_t*)mem)[1]; case 1: ((uint8_t*)&tmp)[0] = ((uint8_t*)mem)[0]; default: break; } #endif return tmp; } 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]; return (ld->bufa << (32 - ld->bits_left)) >> (32 - bits); } bits -= ld->bits_left; //return ((ld->bufa & bitmask[ld->bits_left]) << bits) | (ld->bufb >> (32 - bits)); return ((ld->bufa & ((1<<ld->bits_left)-1)) << 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 { faad_flushbits_ex(ld, bits); } } /* return next n bits (right adjusted) */ static /*INLINE*/ uint32_t faad_getbits(bitfile *ld, uint32_t n DEBUGDEC) { uint32_t ret; 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) { ld->bits_left--; r = (uint8_t)((ld->bufa >> ld->bits_left) & 1); return r; } /* bits_left == 0 */ #if 0 r = (uint8_t)(ld->bufb >> 31); faad_flushbits_ex(ld, 1); #else r = (uint8_t)faad_getbits(ld, 1); #endif 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); ld->bufb = tmp; ld->start--; ld->bits_left += (32 - bits); if (ld->bytes_left < 4) { ld->error = 1; ld->bytes_left = 0; } else { ld->bytes_left -= 4; } // if (ld->bytes_left == 0) // ld->no_more_reading = 1; } } static /*INLINE*/ uint32_t faad_getbits_rev(bitfile *ld, uint32_t n DEBUGDEC) { uint32_t ret; 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 DRM /* CRC lookup table for G8 polynome in DRM standard */ static const uint8_t crc_table_G8[256] = { 0x0, 0x1d, 0x3a, 0x27, 0x74, 0x69, 0x4e, 0x53, 0xe8, 0xf5, 0xd2, 0xcf, 0x9c, 0x81, 0xa6, 0xbb, 0xcd, 0xd0, 0xf7, 0xea, 0xb9, 0xa4, 0x83, 0x9e, 0x25, 0x38, 0x1f, 0x2, 0x51, 0x4c, 0x6b, 0x76, 0x87, 0x9a, 0xbd, 0xa0, 0xf3, 0xee, 0xc9, 0xd4, 0x6f, 0x72, 0x55, 0x48, 0x1b, 0x6, 0x21, 0x3c, 0x4a, 0x57, 0x70, 0x6d, 0x3e, 0x23, 0x4, 0x19, 0xa2, 0xbf, 0x98, 0x85, 0xd6, 0xcb, 0xec, 0xf1, 0x13, 0xe, 0x29, 0x34, 0x67, 0x7a, 0x5d, 0x40, 0xfb, 0xe6, 0xc1, 0xdc, 0x8f, 0x92, 0xb5, 0xa8, 0xde, 0xc3, 0xe4, 0xf9, 0xaa, 0xb7, 0x90, 0x8d, 0x36, 0x2b, 0xc, 0x11, 0x42, 0x5f, 0x78, 0x65, 0x94, 0x89, 0xae, 0xb3, 0xe0, 0xfd, 0xda, 0xc7, 0x7c, 0x61, 0x46, 0x5b, 0x8, 0x15, 0x32, 0x2f, 0x59, 0x44, 0x63, 0x7e, 0x2d, 0x30, 0x17, 0xa, 0xb1, 0xac, 0x8b, 0x96, 0xc5, 0xd8, 0xff, 0xe2, 0x26, 0x3b, 0x1c, 0x1, 0x52, 0x4f, 0x68, 0x75, 0xce, 0xd3, 0xf4, 0xe9, 0xba, 0xa7, 0x80, 0x9d, 0xeb, 0xf6, 0xd1, 0xcc, 0x9f, 0x82, 0xa5, 0xb8, 0x3, 0x1e, 0x39, 0x24, 0x77, 0x6a, 0x4d, 0x50, 0xa1, 0xbc, 0x9b, 0x86, 0xd5, 0xc8, 0xef, 0xf2, 0x49, 0x54, 0x73, 0x6e, 0x3d, 0x20, 0x7, 0x1a, 0x6c, 0x71, 0x56, 0x4b, 0x18, 0x5, 0x22, 0x3f, 0x84, 0x99, 0xbe, 0xa3, 0xf0, 0xed, 0xca, 0xd7, 0x35, 0x28, 0xf, 0x12, 0x41, 0x5c, 0x7b, 0x66, 0xdd, 0xc0, 0xe7, 0xfa, 0xa9, 0xb4, 0x93, 0x8e, 0xf8, 0xe5, 0xc2, 0xdf, 0x8c, 0x91, 0xb6, 0xab, 0x10, 0xd, 0x2a, 0x37, 0x64, 0x79, 0x5e, 0x43, 0xb2, 0xaf, 0x88, 0x95, 0xc6, 0xdb, 0xfc, 0xe1, 0x5a, 0x47, 0x60, 0x7d, 0x2e, 0x33, 0x14, 0x9, 0x7f, 0x62, 0x45, 0x58, 0xb, 0x16, 0x31, 0x2c, 0x97, 0x8a, 0xad, 0xb0, 0xe3, 0xfe, 0xd9, 0xc4, }; static uint8_t faad_check_CRC(bitfile *ld, uint16_t len) { int bytes, rem; unsigned int CRC; unsigned int r=255; /* Initialize to all ones */ /* CRC polynome used x^8 + x^4 + x^3 + x^2 +1 */ #define GPOLY 0435 faad_rewindbits(ld); CRC = (unsigned int) ~faad_getbits(ld, 8 DEBUGVAR(1,999,"faad_check_CRC(): CRC")) & 0xFF; /* CRC is stored inverted */ bytes = len >> 3; rem = len & 0x7; for (; bytes > 0; bytes--) { r = crc_table_G8[( r ^ faad_getbits(ld, 8 DEBUGVAR(1,998,"")) ) & 0xFF]; } for (; rem > 0; rem--) { r = ( (r << 1) ^ (( ( faad_get1bit(ld DEBUGVAR(1,998,"")) & 1) ^ ((r >> 7) & 1)) * GPOLY )) & 0xFF; } if (r != CRC) // if (0) { return 28; } else { return 0; } } static uint8_t tabFlipbits[256] = { 0,128,64,192,32,160,96,224,16,144,80,208,48,176,112,240, 8,136,72,200,40,168,104,232,24,152,88,216,56,184,120,248, 4,132,68,196,36,164,100,228,20,148,84,212,52,180,116,244, 12,140,76,204,44,172,108,236,28,156,92,220,60,188,124,252, 2,130,66,194,34,162,98,226,18,146,82,210,50,178,114,242, 10,138,74,202,42,170,106,234,26,154,90,218,58,186,122,250, 6,134,70,198,38,166,102,230,22,150,86,214,54,182,118,246, 14,142,78,206,46,174,110,238,30,158,94,222,62,190,126,254, 1,129,65,193,33,161,97,225,17,145,81,209,49,177,113,241, 9,137,73,201,41,169,105,233,25,153,89,217,57,185,121,249, 5,133,69,197,37,165,101,229,21,149,85,213,53,181,117,245, 13,141,77,205,45,173,109,237,29,157,93,221,61,189,125,253, 3,131,67,195,35,163,99,227,19,147,83,211,51,179,115,243, 11,139,75,203,43,171,107,235,27,155,91,219,59,187,123,251, 7,135,71,199,39,167,103,231,23,151,87,215,55,183,119,247, 15,143,79,207,47,175,111,239,31,159,95,223,63,191,127,255 }; #endif #ifdef ERROR_RESILIENCE /* Modified bit reading functions for HCR */ typedef struct { /* bit input */ uint32_t bufa; uint32_t bufb; int8_t len; } bits_t; static INLINE uint32_t showbits_hcr(bits_t *ld, uint8_t bits) { if (bits == 0) return 0; if (ld->len <= 32) { /* huffman_spectral_data_2 needs to read more than may be available, bits maybe > ld->len, deliver 0 than */ if (ld->len >= bits) return ((ld->bufa >> (ld->len - bits)) & (0xFFFFFFFF >> (32 - bits))); else return ((ld->bufa << (bits - ld->len)) & (0xFFFFFFFF >> (32 - bits))); } else { if ((ld->len - bits) < 32) { return ( (ld->bufb & (0xFFFFFFFF >> (64 - ld->len))) << (bits - ld->len + 32)) | (ld->bufa >> (ld->len - bits)); } else { return ((ld->bufb >> (ld->len - bits - 32)) & (0xFFFFFFFF >> (32 - bits))); } } } /* return 1 if position is outside of buffer, 0 otherwise */ static INLINE int8_t flushbits_hcr( bits_t *ld, uint8_t bits) { ld->len -= bits; if (ld->len <0) { ld->len = 0; return 1; } else { return 0; } } static INLINE int8_t getbits_hcr(bits_t *ld, uint8_t n, uint32_t *result) { *result = showbits_hcr(ld, n); return flushbits_hcr(ld, n); } static INLINE int8_t get1bit_hcr(bits_t *ld, uint8_t *result) { uint32_t res; int8_t ret; ret = getbits_hcr(ld, 1, &res); *result = (int8_t)(res & 1); return ret; } #endif #ifdef __cplusplus } #endif #endif