ref: 54d7f35236ac517e28ee4cb4df08804d3c7e0421
dir: /libfaac/huff2.c/
/****************************************************************************
Huffman coding
Copyright (C) 2017 Krzysztof Nikiel
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 3 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, see <http://www.gnu.org/licenses/>.
****************************************************************************/
#include "util.h"
#include "coder.h"
#include "huffdata.h"
#include "huff2.h"
#include "bitstream.h"
#ifdef DRM
static int vcb11;
#endif
static int escape(int x, int *code)
{
int preflen = 0;
int base = 32;
if (x >= 8192)
{
fprintf(stderr, "%s(%d): x_quant >= 8192\n", __FILE__, __LINE__);
return 0;
}
*code = 0;
while (base <= x)
{
base <<= 1;
*code <<= 1;
*code |= 1;
preflen++;
}
base >>= 1;
// separator
*code <<= 1;
*code <<= (preflen + 4);
*code |= (x - base);
return (preflen << 1) + 5;
}
#ifdef DRM
# define DRMDATA if(coder){coder->num_data_cw[coder->cur_cw++]=1;\
coder->iLenReordSpData+=blen;if(coder->iLenLongestCW<blen)\
coder->iLenLongestCW=blen;}
#else
# define DRMDATA
#endif
#define arrlen(array) (sizeof(array) / sizeof(*array))
static int huffcode(int *qs /* quantized spectrum */,
int len,
int bnum,
CoderInfo *coder)
{
static hcode16_t * const hmap[12] = {0, book01, book02, book03, book04,
book05, book06, book07, book08, book09, book10, book11};
hcode16_t *book;
int cnt;
int bits = 0, blen;
int ofs, *qp;
int data;
int idx;
int datacnt;
#ifdef DRM
int drmbits = 0;
int maxesc = 0;
#endif
if (coder)
datacnt = coder->datacnt;
else
datacnt = 0;
book = hmap[bnum];
switch (bnum)
{
#ifdef DRM
case HCB_ZERO:
case HCB_INTENSITY:
case HCB_INTENSITY2:
for(ofs = 0; ofs < len; ofs += 4)
{
coder->s[datacnt].data = 0;
coder->s[datacnt++].len = 0;
coder->num_data_cw[coder->cur_cw++] = 1;
}
break;
#endif
case 1:
case 2:
for(ofs = 0; ofs < len; ofs += 4)
{
qp = qs+ofs;
idx = 27 * qp[0] + 9 * qp[1] + 3 * qp[2] + qp[3] + 40;
if (idx < 0 || idx >= arrlen(book01))
{
return -1;
}
blen = book[idx].len;
if (coder)
{
data = book[idx].data;
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
DRMDATA;
}
bits += blen;
}
break;
case 3:
case 4:
for(ofs = 0; ofs < len; ofs += 4)
{
qp = qs+ofs;
idx = 27 * abs(qp[0]) + 9 * abs(qp[1]) + 3 * abs(qp[2]) + abs(qp[3]);
if (idx < 0 || idx >= arrlen(book03))
{
return -1;
}
blen = book[idx].len;
if (!coder)
{
// add sign bits
for(cnt = 0; cnt < 4; cnt++)
if(qp[cnt])
blen++;
}
else
{
data = book[idx].data;
// add sign bits
for(cnt = 0; cnt < 4; cnt++)
{
if(qp[cnt])
{
blen++;
data <<= 1;
if (qp[cnt] < 0)
data |= 1;
}
}
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
DRMDATA;
}
bits += blen;
}
break;
case 5:
case 6:
for(ofs = 0; ofs < len; ofs += 2)
{
qp = qs+ofs;
idx = 9 * qp[0] + qp[1] + 40;
if (idx < 0 || idx >= arrlen(book05))
{
return -1;
}
blen = book[idx].len;
if (coder)
{
data = book[idx].data;
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
DRMDATA;
}
bits += blen;
}
break;
case 7:
case 8:
for(ofs = 0; ofs < len; ofs += 2)
{
qp = qs+ofs;
idx = 8 * abs(qp[0]) + abs(qp[1]);
if (idx < 0 || idx >= arrlen(book07))
{
return -1;
}
blen = book[idx].len;
if (!coder)
{
for(cnt = 0; cnt < 2; cnt++)
if(qp[cnt])
blen++;
}
else
{
data = book[idx].data;
for(cnt = 0; cnt < 2; cnt++)
{
if(qp[cnt])
{
blen++;
data <<= 1;
if (qp[cnt] < 0)
data |= 1;
}
}
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
DRMDATA;
}
bits += blen;
}
break;
case 9:
case 10:
for(ofs = 0; ofs < len; ofs += 2)
{
qp = qs+ofs;
idx = 13 * abs(qp[0]) + abs(qp[1]);
if (idx < 0 || idx >= arrlen(book09))
{
return -1;
}
blen = book[idx].len;
if (!coder)
{
for(cnt = 0; cnt < 2; cnt++)
if(qp[cnt])
blen++;
}
else
{
data = book[idx].data;
for(cnt = 0; cnt < 2; cnt++)
{
if(qp[cnt])
{
blen++;
data <<= 1;
if (qp[cnt] < 0)
data |= 1;
}
}
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
DRMDATA;
}
bits += blen;
}
break;
case HCB_ESC:
for(ofs = 0; ofs < len; ofs += 2)
{
int x0, x1;
qp = qs+ofs;
x0 = abs(qp[0]);
x1 = abs(qp[1]);
if (x0 > 16)
x0 = 16;
if (x1 > 16)
x1 = 16;
idx = 17 * x0 + x1;
if (idx < 0 || idx >= arrlen(book11))
{
return -1;
}
blen = book[idx].len;
if (!coder)
{
for(cnt = 0; cnt < 2; cnt++)
if(qp[cnt])
blen++;
}
else
{
data = book[idx].data;
for(cnt = 0; cnt < 2; cnt++)
{
if(qp[cnt])
{
blen++;
data <<= 1;
if (qp[cnt] < 0)
data |= 1;
}
}
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
#ifdef DRM
coder->num_data_cw[coder->cur_cw] = 1;
drmbits = blen;
#endif
}
bits += blen;
if (x0 >= 16)
{
blen = escape(abs(qp[0]), &data);
if (coder)
{
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
#ifdef DRM
coder->num_data_cw[coder->cur_cw]++;
drmbits += blen;
if (maxesc < data)
maxesc = data;
#endif
}
bits += blen;
}
if (x1 >= 16)
{
blen = escape(abs(qp[1]), &data);
if (coder)
{
coder->s[datacnt].data = data;
coder->s[datacnt++].len = blen;
#ifdef DRM
coder->num_data_cw[coder->cur_cw]++;
drmbits += blen;
if (maxesc < data)
maxesc = data;
#endif
}
bits += blen;
}
#ifdef DRM
coder->iLenReordSpData += drmbits;
if (coder->iLenLongestCW < drmbits)
coder->iLenLongestCW = drmbits;
coder->cur_cw++;
#endif
}
#ifdef DRM
/* VCB11: check which codebook should be used using max escape sequence */
/* 8.5.3.1.3, table 157 */
if (maxesc <= 15)
vcb11 = 16;
else if (maxesc <= 31)
vcb11 = 17;
else if (maxesc <= 47)
vcb11 = 18;
else if (maxesc <= 63)
vcb11 = 19;
else if (maxesc <= 95)
vcb11 = 20;
else if (maxesc <= 127)
vcb11 = 21;
else if (maxesc <= 159)
vcb11 = 22;
else if (maxesc <= 191)
vcb11 = 23;
else if (maxesc <= 223)
vcb11 = 24;
else if (maxesc <= 255)
vcb11 = 25;
else if (maxesc <= 319)
vcb11 = 26;
else if (maxesc <= 383)
vcb11 = 27;
else if (maxesc <= 511)
vcb11 = 28;
else if (maxesc <= 767)
vcb11 = 29;
else if (maxesc <= 1023)
vcb11 = 30;
else if (maxesc <= 2047)
vcb11 = 31;
/* else: codebook 11 -> it is already 11 */
#endif
break;
default:
fprintf(stderr, "%s(%d) book %d out of range\n", __FILE__, __LINE__, bnum);
return -1;
}
if (coder)
coder->datacnt = datacnt;
return bits;
}
int huffbook(CoderInfo *coder,
int *qs /* quantized spectrum */,
int len)
{
int cnt;
int maxq = 0;
int bookmin, lenmin;
for (cnt = 0; cnt < len; cnt++)
{
int q = abs(qs[cnt]);
if (maxq < q)
maxq = q;
}
#define BOOKMIN(n)bookmin=n;lenmin=huffcode(qs,len,bookmin,0);if(huffcode(qs,len,bookmin+1,0)<lenmin)bookmin++;
if (maxq < 1)
{
bookmin = HCB_ZERO;
lenmin = 0;
}
else if (maxq < 2)
{
BOOKMIN(1);
}
else if (maxq < 3)
{
BOOKMIN(3);
}
else if (maxq < 5)
{
BOOKMIN(5);
}
else if (maxq < 8)
{
BOOKMIN(7);
}
else if (maxq < 13)
{
BOOKMIN(9);
}
else
{
bookmin = HCB_ESC;
}
#ifdef DRM
vcb11 = 0;
huffcode(qs, len, bookmin, coder);
if (vcb11)
bookmin = vcb11;
#else
if (bookmin > HCB_ZERO)
huffcode(qs, len, bookmin, coder);
#endif
coder->book[coder->bandcnt] = bookmin;
return 0;
}
int writebooks(CoderInfo *coder, BitStream *stream, int write)
{
int bits = 0;
int maxcnt, cntbits;
int group;
int bookbits = 4;
#ifdef DRM
bookbits = 5; /* 5 bits in case of VCB11 */
#endif
if (coder->block_type == ONLY_SHORT_WINDOW){
maxcnt = 7;
cntbits = 3;
} else {
maxcnt = 31;
cntbits = 5;
}
for (group = 0; group < coder->groups.n; group++)
{
int band = group * coder->sfbn;
int maxband = band + coder->sfbn;
while (band < maxband)
{
int book = coder->book[band++];
int bookcnt = 1;
if (write) {
PutBit(stream, book, bookbits);
}
bits += bookbits;
#ifdef DRM
/* sect_len is not transmitted in case the codebook for a */
/* section is 11 or in the range of 16 and 31 */
if ((book == 11) || ((book >= 16) && (book <= 32)))
continue;
#endif
if (band < maxband)
{
while (book == coder->book[band])
{
band++;
bookcnt++;
if (band >= maxband)
break;
}
}
while (bookcnt >= maxcnt)
{
if (write)
PutBit(stream, maxcnt, cntbits);
bits += cntbits;
bookcnt -= maxcnt;
}
if (write)
PutBit(stream, bookcnt, cntbits);
bits += cntbits;
}
}
return bits;
}
int writesf(CoderInfo *coder, BitStream *stream, int write)
{
int cnt;
int bits = 0;
int diff, length;
int lastsf;
int lastis;
int lastpns;
int initpns = 1;
lastsf = coder->global_gain;
lastis = 0;
lastpns = coder->global_gain - 90;
// fixme: move range check to quantizer
for (cnt = 0; cnt < coder->bandcnt; cnt++)
{
int book = coder->book[cnt];
if ((book == HCB_INTENSITY) || (book== HCB_INTENSITY2))
{
diff = coder->sf[cnt] - lastis;
if (diff > 60)
diff = 60;
if (diff < -60)
diff = -60;
length = book12[60 + diff].len;
bits += length;
lastis += diff;
if (write)
PutBit(stream, book12[60 + diff].data, length);
}
else if (book == HCB_PNS)
{
diff = coder->sf[cnt] - lastpns;
if (initpns)
{
initpns = 0;
length = 9;
bits += length;
lastpns += diff;
if (write)
PutBit(stream, diff + 256, length);
continue;
}
if (diff > 60)
diff = 60;
if (diff < -60)
diff = -60;
length = book12[60 + diff].len;
bits += length;
lastpns += diff;
if (write)
PutBit(stream, book12[60 + diff].data, length);
}
else if (book)
{
diff = coder->sf[cnt] - lastsf;
if (diff > 60)
diff = 60;
if (diff < -60)
diff = -60;
length = book12[60 + diff].len;
bits += length;
lastsf += diff;
if (write)
PutBit(stream, book12[60 + diff].data, length);
}
}
return bits;
}