ref: 3ba088193fc0e9b022957fb348cfdfe1d60daab7
dir: /libfaad/huffman.c/
/*
** 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: huffman.c,v 1.26 2007/11/01 12:33:30 menno Exp $
**/
#include "common.h"
#include "structs.h"
#include "bits.h"
#include "huffman.h"
#include "codebook/hcb.h"
/* static function declarations */
static INLINE void huffman_sign_bits(bitfile *ld, int16_t *sp, uint8_t len);
static INLINE int16_t huffman_getescape(bitfile *ld, int16_t sp);
static uint8_t huffman_2step_quad(uint8_t cb, bitfile *ld, int16_t *sp);
static uint8_t huffman_2step_quad_sign(uint8_t cb, bitfile *ld, int16_t *sp);
static uint8_t huffman_2step_pair(uint8_t cb, bitfile *ld, int16_t *sp);
static uint8_t huffman_2step_pair_sign(uint8_t cb, bitfile *ld, int16_t *sp);
static uint8_t huffman_binary_quad(uint8_t cb, bitfile *ld, int16_t *sp);
static uint8_t huffman_binary_quad_sign(uint8_t cb, bitfile *ld, int16_t *sp);
static uint8_t huffman_binary_pair(uint8_t cb, bitfile *ld, int16_t *sp);
static uint8_t huffman_binary_pair_sign(uint8_t cb, bitfile *ld, int16_t *sp);
static int16_t huffman_codebook(uint8_t i);
static void vcb11_check_LAV(uint8_t cb, int16_t *sp);
int8_t huffman_scale_factor(bitfile *ld)
{
uint16_t offset = 0;
while (hcb_sf[offset][1])
{
uint8_t b = faad_get1bit(ld
DEBUGVAR(1,255,"huffman_scale_factor()"));
offset += hcb_sf[offset][b];
if (offset > 240)
{
/* printf("ERROR: offset into hcb_sf = %d >240!\n", offset); */
return -1;
}
}
return hcb_sf[offset][0];
}
hcb *hcb_table[] = {
0, hcb1_1, hcb2_1, 0, hcb4_1, 0, hcb6_1, 0, hcb8_1, 0, hcb10_1, hcb11_1
};
hcb_2_quad *hcb_2_quad_table[] = {
0, hcb1_2, hcb2_2, 0, hcb4_2, 0, 0, 0, 0, 0, 0, 0
};
hcb_2_pair *hcb_2_pair_table[] = {
0, 0, 0, 0, 0, 0, hcb6_2, 0, hcb8_2, 0, hcb10_2, hcb11_2
};
hcb_bin_pair *hcb_bin_table[] = {
0, 0, 0, 0, 0, hcb5, 0, hcb7, 0, hcb9, 0, 0
};
uint8_t hcbN[] = { 0, 5, 5, 0, 5, 0, 5, 0, 5, 0, 6, 5 };
/* defines whether a huffman codebook is unsigned or not */
/* Table 4.6.2 */
uint8_t unsigned_cb[] = { 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0,
/* codebook 16 to 31 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
};
int hcb_2_quad_table_size[] = { 0, 114, 86, 0, 185, 0, 0, 0, 0, 0, 0, 0 };
int hcb_2_pair_table_size[] = { 0, 0, 0, 0, 0, 0, 126, 0, 83, 0, 210, 373 };
int hcb_bin_table_size[] = { 0, 0, 0, 161, 0, 161, 0, 127, 0, 337, 0, 0 };
static INLINE void huffman_sign_bits(bitfile *ld, int16_t *sp, uint8_t len)
{
uint8_t i;
for (i = 0; i < len; i++)
{
if(sp[i])
{
if(faad_get1bit(ld
DEBUGVAR(1,5,"huffman_sign_bits(): sign bit")) & 1)
{
sp[i] = -sp[i];
}
}
}
}
static INLINE int16_t huffman_getescape(bitfile *ld, int16_t sp)
{
uint8_t neg, i;
int16_t j;
int16_t off;
if (sp < 0)
{
if (sp != -16)
return sp;
neg = 1;
} else {
if (sp != 16)
return sp;
neg = 0;
}
for (i = 4; ; i++)
{
if (faad_get1bit(ld
DEBUGVAR(1,6,"huffman_getescape(): escape size")) == 0)
{
break;
}
}
off = (int16_t)faad_getbits(ld, i
DEBUGVAR(1,9,"huffman_getescape(): escape"));
j = off | (1<<i);
if (neg)
j = -j;
return j;
}
static uint8_t huffman_2step_quad(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint32_t cw;
uint16_t offset = 0;
uint8_t extra_bits;
cw = faad_showbits(ld, hcbN[cb]);
offset = hcb_table[cb][cw].offset;
extra_bits = hcb_table[cb][cw].extra_bits;
if (extra_bits)
{
/* we know for sure it's more than hcbN[cb] bits long */
faad_flushbits(ld, hcbN[cb]);
offset += (uint16_t)faad_showbits(ld, extra_bits);
faad_flushbits(ld, hcb_2_quad_table[cb][offset].bits - hcbN[cb]);
} else {
faad_flushbits(ld, hcb_2_quad_table[cb][offset].bits);
}
if (offset > hcb_2_quad_table_size[cb])
{
/* printf("ERROR: offset into hcb_2_quad_table = %d >%d!\n", offset,
hcb_2_quad_table_size[cb]); */
return 10;
}
sp[0] = hcb_2_quad_table[cb][offset].x;
sp[1] = hcb_2_quad_table[cb][offset].y;
sp[2] = hcb_2_quad_table[cb][offset].v;
sp[3] = hcb_2_quad_table[cb][offset].w;
return 0;
}
static uint8_t huffman_2step_quad_sign(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint8_t err = huffman_2step_quad(cb, ld, sp);
huffman_sign_bits(ld, sp, QUAD_LEN);
return err;
}
static uint8_t huffman_2step_pair(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint32_t cw;
uint16_t offset = 0;
uint8_t extra_bits;
cw = faad_showbits(ld, hcbN[cb]);
offset = hcb_table[cb][cw].offset;
extra_bits = hcb_table[cb][cw].extra_bits;
if (extra_bits)
{
/* we know for sure it's more than hcbN[cb] bits long */
faad_flushbits(ld, hcbN[cb]);
offset += (uint16_t)faad_showbits(ld, extra_bits);
faad_flushbits(ld, hcb_2_pair_table[cb][offset].bits - hcbN[cb]);
} else {
faad_flushbits(ld, hcb_2_pair_table[cb][offset].bits);
}
if (offset > hcb_2_pair_table_size[cb])
{
/* printf("ERROR: offset into hcb_2_pair_table = %d >%d!\n", offset,
hcb_2_pair_table_size[cb]); */
return 10;
}
sp[0] = hcb_2_pair_table[cb][offset].x;
sp[1] = hcb_2_pair_table[cb][offset].y;
return 0;
}
static uint8_t huffman_2step_pair_sign(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint8_t err = huffman_2step_pair(cb, ld, sp);
huffman_sign_bits(ld, sp, PAIR_LEN);
return err;
}
static uint8_t huffman_binary_quad(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint16_t offset = 0;
while (!hcb3[offset].is_leaf)
{
uint8_t b = faad_get1bit(ld
DEBUGVAR(1,255,"huffman_spectral_data():3"));
offset += hcb3[offset].data[b];
}
if (offset > hcb_bin_table_size[cb])
{
/* printf("ERROR: offset into hcb_bin_table = %d >%d!\n", offset,
hcb_bin_table_size[cb]); */
return 10;
}
sp[0] = hcb3[offset].data[0];
sp[1] = hcb3[offset].data[1];
sp[2] = hcb3[offset].data[2];
sp[3] = hcb3[offset].data[3];
return 0;
}
static uint8_t huffman_binary_quad_sign(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint8_t err = huffman_binary_quad(cb, ld, sp);
huffman_sign_bits(ld, sp, QUAD_LEN);
return err;
}
static uint8_t huffman_binary_pair(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint16_t offset = 0;
while (!hcb_bin_table[cb][offset].is_leaf)
{
uint8_t b = faad_get1bit(ld
DEBUGVAR(1,255,"huffman_spectral_data():9"));
offset += hcb_bin_table[cb][offset].data[b];
}
if (offset > hcb_bin_table_size[cb])
{
/* printf("ERROR: offset into hcb_bin_table = %d >%d!\n", offset,
hcb_bin_table_size[cb]); */
return 10;
}
sp[0] = hcb_bin_table[cb][offset].data[0];
sp[1] = hcb_bin_table[cb][offset].data[1];
return 0;
}
static uint8_t huffman_binary_pair_sign(uint8_t cb, bitfile *ld, int16_t *sp)
{
uint8_t err = huffman_binary_pair(cb, ld, sp);
huffman_sign_bits(ld, sp, PAIR_LEN);
return err;
}
static int16_t huffman_codebook(uint8_t i)
{
static const uint32_t data = 16428320;
if (i == 0) return (int16_t)(data >> 16) & 0xFFFF;
else return (int16_t)data & 0xFFFF;
}
static void vcb11_check_LAV(uint8_t cb, int16_t *sp)
{
static const uint16_t vcb11_LAV_tab[] = {
16, 31, 47, 63, 95, 127, 159, 191, 223,
255, 319, 383, 511, 767, 1023, 2047
};
uint16_t max = 0;
if (cb < 16 || cb > 31)
return;
max = vcb11_LAV_tab[cb - 16];
if ((abs(sp[0]) > max) || (abs(sp[1]) > max))
{
sp[0] = 0;
sp[1] = 0;
}
}
uint8_t huffman_spectral_data(uint8_t cb, bitfile *ld, int16_t *sp)
{
switch (cb)
{
case 1: /* 2-step method for data quadruples */
case 2:
return huffman_2step_quad(cb, ld, sp);
case 3: /* binary search for data quadruples */
return huffman_binary_quad_sign(cb, ld, sp);
case 4: /* 2-step method for data quadruples */
return huffman_2step_quad_sign(cb, ld, sp);
case 5: /* binary search for data pairs */
return huffman_binary_pair(cb, ld, sp);
case 6: /* 2-step method for data pairs */
return huffman_2step_pair(cb, ld, sp);
case 7: /* binary search for data pairs */
case 9:
return huffman_binary_pair_sign(cb, ld, sp);
case 8: /* 2-step method for data pairs */
case 10:
return huffman_2step_pair_sign(cb, ld, sp);
case 12: {
uint8_t err = huffman_2step_pair(11, ld, sp);
sp[0] = huffman_codebook(0); sp[1] = huffman_codebook(1);
return err; }
case 11:
{
uint8_t err = huffman_2step_pair_sign(11, ld, sp);
sp[0] = huffman_getescape(ld, sp[0]);
sp[1] = huffman_getescape(ld, sp[1]);
return err;
}
#ifdef ERROR_RESILIENCE
/* VCB11 uses codebook 11 */
case 16: case 17: case 18: case 19: case 20: case 21: case 22: case 23:
case 24: case 25: case 26: case 27: case 28: case 29: case 30: case 31:
{
uint8_t err = huffman_2step_pair_sign(11, ld, sp);
sp[0] = huffman_getescape(ld, sp[0]);
sp[1] = huffman_getescape(ld, sp[1]);
/* check LAV (Largest Absolute Value) */
/* this finds errors in the ESCAPE signal */
vcb11_check_LAV(cb, sp);
return err;
}
#endif
default:
/* Non existent codebook number, something went wrong */
return 11;
}
return 0;
}
#ifdef ERROR_RESILIENCE
/* Special version of huffman_spectral_data
Will not read from a bitfile but a bits_t structure.
Will keep track of the bits decoded and return the number of bits remaining.
Do not read more than ld->len, return -1 if codeword would be longer */
int8_t huffman_spectral_data_2(uint8_t cb, bits_t *ld, int16_t *sp)
{
uint32_t cw;
uint16_t offset = 0;
uint8_t extra_bits;
uint8_t i, vcb11 = 0;
switch (cb)
{
case 1: /* 2-step method for data quadruples */
case 2:
case 4:
cw = showbits_hcr(ld, hcbN[cb]);
offset = hcb_table[cb][cw].offset;
extra_bits = hcb_table[cb][cw].extra_bits;
if (extra_bits)
{
/* we know for sure it's more than hcbN[cb] bits long */
if ( flushbits_hcr(ld, hcbN[cb]) ) return -1;
offset += (uint16_t)showbits_hcr(ld, extra_bits);
if ( flushbits_hcr(ld, hcb_2_quad_table[cb][offset].bits - hcbN[cb]) ) return -1;
} else {
if ( flushbits_hcr(ld, hcb_2_quad_table[cb][offset].bits) ) return -1;
}
sp[0] = hcb_2_quad_table[cb][offset].x;
sp[1] = hcb_2_quad_table[cb][offset].y;
sp[2] = hcb_2_quad_table[cb][offset].v;
sp[3] = hcb_2_quad_table[cb][offset].w;
break;
case 6: /* 2-step method for data pairs */
case 8:
case 10:
case 11:
/* VCB11 uses codebook 11 */
case 16: case 17: case 18: case 19: case 20: case 21: case 22: case 23:
case 24: case 25: case 26: case 27: case 28: case 29: case 30: case 31:
if (cb >= 16)
{
/* store the virtual codebook */
vcb11 = cb;
cb = 11;
}
cw = showbits_hcr(ld, hcbN[cb]);
offset = hcb_table[cb][cw].offset;
extra_bits = hcb_table[cb][cw].extra_bits;
if (extra_bits)
{
/* we know for sure it's more than hcbN[cb] bits long */
if ( flushbits_hcr(ld, hcbN[cb]) ) return -1;
offset += (uint16_t)showbits_hcr(ld, extra_bits);
if ( flushbits_hcr(ld, hcb_2_pair_table[cb][offset].bits - hcbN[cb]) ) return -1;
} else {
if ( flushbits_hcr(ld, hcb_2_pair_table[cb][offset].bits) ) return -1;
}
sp[0] = hcb_2_pair_table[cb][offset].x;
sp[1] = hcb_2_pair_table[cb][offset].y;
break;
case 3: /* binary search for data quadruples */
while (!hcb3[offset].is_leaf)
{
uint8_t b;
if ( get1bit_hcr(ld, &b) ) return -1;
offset += hcb3[offset].data[b];
}
sp[0] = hcb3[offset].data[0];
sp[1] = hcb3[offset].data[1];
sp[2] = hcb3[offset].data[2];
sp[3] = hcb3[offset].data[3];
break;
case 5: /* binary search for data pairs */
case 7:
case 9:
while (!hcb_bin_table[cb][offset].is_leaf)
{
uint8_t b;
if (get1bit_hcr(ld, &b) ) return -1;
offset += hcb_bin_table[cb][offset].data[b];
}
sp[0] = hcb_bin_table[cb][offset].data[0];
sp[1] = hcb_bin_table[cb][offset].data[1];
break;
}
/* decode sign bits */
if (unsigned_cb[cb])
{
for(i = 0; i < ((cb < FIRST_PAIR_HCB) ? QUAD_LEN : PAIR_LEN); i++)
{
if(sp[i])
{
uint8_t b;
if ( get1bit_hcr(ld, &b) ) return -1;
if (b != 0) {
sp[i] = -sp[i];
}
}
}
}
/* decode huffman escape bits */
if ((cb == ESC_HCB) || (cb >= 16))
{
uint8_t k;
for (k = 0; k < 2; k++)
{
if ((sp[k] == 16) || (sp[k] == -16))
{
uint8_t neg, i;
int32_t j;
uint32_t off;
neg = (sp[k] < 0) ? 1 : 0;
for (i = 4; ; i++)
{
uint8_t b;
if (get1bit_hcr(ld, &b))
return -1;
if (b == 0)
break;
}
if (getbits_hcr(ld, i, &off))
return -1;
j = off + (1<<i);
sp[k] = (int16_t)((neg) ? -j : j);
}
}
if (vcb11 != 0)
{
/* check LAV (Largest Absolute Value) */
/* this finds errors in the ESCAPE signal */
vcb11_check_LAV(vcb11, sp);
}
}
return ld->len;
}
#endif