summaryrefslogtreecommitdiffstats
path: root/src/lib/jpeg.c
blob: 8d370ec67b199d7a2aa8ca114a87c05a36bcdad3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2001 Michael Schroeder
 *
 * 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; version 2 of the License.
 *
 * 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.
 */

/*
 * a tiny jpeg decoder.
 *
 * written in August 2001 by Michael Schroeder <mls@suse.de>
 *
 */

#define __LITTLE_ENDIAN
#include <string.h>
#include "jpeg.h"
#define ISHIFT 11

#define IFIX(a) ((int)((a) * (1 << ISHIFT) + .5))
#define IMULT(a, b) (((a) * (b)) >> ISHIFT)
#define ITOINT(a) ((a) >> ISHIFT)

#ifndef __P
# define __P(x) x
#endif

/* special markers */
#define M_BADHUFF	-1
#define M_EOF		0x80

struct in {
	unsigned char *p;
	unsigned int bits;
	int left;
	int marker;

	int (*func) __P((void *));
	void *data;
};

/*********************************/
struct dec_hufftbl;
struct enc_hufftbl;

union hufftblp {
	struct dec_hufftbl *dhuff;
	struct enc_hufftbl *ehuff;
};

struct scan {
	int dc;			/* old dc value */

	union hufftblp hudc;
	union hufftblp huac;
	int next;		/* when to switch to next scan */

	int cid;		/* component id */
	int hv;			/* horiz/vert, copied from comp */
	int tq;			/* quant tbl, copied from comp */
};

/*********************************/

#define DECBITS 10		/* seems to be the optimum */

struct dec_hufftbl {
	int maxcode[17];
	int valptr[16];
	unsigned char vals[256];
	unsigned int llvals[1 << DECBITS];
};

static void decode_mcus __P((struct in *, int *, int, struct scan *, int *));
static int dec_readmarker __P((struct in *));
static void dec_makehuff __P((struct dec_hufftbl *, int *, unsigned char *));

static void setinput __P((struct in *, unsigned char *));
/*********************************/

#undef PREC
#define PREC int

static void idctqtab __P((unsigned char *, PREC *));
static void idct __P((int *, int *, PREC *, PREC, int));
static void scaleidctqtab __P((PREC *, PREC));

/*********************************/

static void initcol __P((PREC[][64]));

static void col221111 __P((int *, unsigned char *, int));
static void col221111_16 __P((int *, unsigned char *, int));
static void col221111_32 __P((int *, unsigned char *, int));

/*********************************/

#define M_SOI	0xd8
#define M_APP0	0xe0
#define M_DQT	0xdb
#define M_SOF0	0xc0
#define M_DHT   0xc4
#define M_DRI	0xdd
#define M_SOS	0xda
#define M_RST0	0xd0
#define M_EOI	0xd9
#define M_COM	0xfe

static unsigned char *datap;

static int getbyte(void)
{
	return *datap++;
}

static int getword(void)
{
	int c1, c2;
	c1 = *datap++;
	c2 = *datap++;
	return c1 << 8 | c2;
}

struct comp {
	int cid;
	int hv;
	int tq;
};

#define MAXCOMP 4
struct jpginfo {
	int nc;			/* number of components */
	int ns;			/* number of scans */
	int dri;		/* restart interval */
	int nm;			/* mcus til next marker */
	int rm;			/* next restart marker */
};

static struct jpginfo info;
static struct comp comps[MAXCOMP];

static struct scan dscans[MAXCOMP];

static unsigned char quant[4][64];

static struct dec_hufftbl dhuff[4];

#define dec_huffdc (dhuff + 0)
#define dec_huffac (dhuff + 2)

static struct in glob_in;

static int readtables(int till)
{
	int m, l, i, j, lq, pq, tq;
	int tc, th, tt;

	for (;;) {
		if (getbyte() != 0xff)
			return -1;
		if ((m = getbyte()) == till)
			break;

		switch (m) {
		case 0xc2:
			return 0;

		case M_DQT:
			lq = getword();
			while (lq > 2) {
				pq = getbyte();
				tq = pq & 15;
				if (tq > 3)
					return -1;
				pq >>= 4;
				if (pq != 0)
					return -1;
				for (i = 0; i < 64; i++)
					quant[tq][i] = getbyte();
				lq -= 64 + 1;
			}
			break;

		case M_DHT:
			l = getword();
			while (l > 2) {
				int hufflen[16], k;
				unsigned char huffvals[256];

				tc = getbyte();
				th = tc & 15;
				tc >>= 4;
				tt = tc * 2 + th;
				if (tc > 1 || th > 1)
					return -1;
				for (i = 0; i < 16; i++)
					hufflen[i] = getbyte();
				l -= 1 + 16;
				k = 0;
				for (i = 0; i < 16; i++) {
					for (j = 0; j < hufflen[i]; j++)
						huffvals[k++] = getbyte();
					l -= hufflen[i];
				}
				dec_makehuff(dhuff + tt, hufflen,
					     huffvals);
			}
			break;

		case M_DRI:
			l = getword();
			info.dri = getword();
			break;

		default:
			l = getword();
			while (l-- > 2)
				getbyte();
			break;
		}
	}
	return 0;
}

static void dec_initscans(void)
{
	int i;

	info.nm = info.dri + 1;
	info.rm = M_RST0;
	for (i = 0; i < info.ns; i++)
		dscans[i].dc = 0;
}

static int dec_checkmarker(void)
{
	int i;

	if (dec_readmarker(&glob_in) != info.rm)
		return -1;
	info.nm = info.dri;
	info.rm = (info.rm + 1) & ~0x08;
	for (i = 0; i < info.ns; i++)
		dscans[i].dc = 0;
	return 0;
}

void jpeg_fetch_size(unsigned char *buf, int *width, int *height)
{
	datap = buf;
	getbyte();
	getbyte();
	readtables(M_SOF0);
	getword();
	getbyte();
	*height = getword();
	*width = getword();
}

int jpeg_check_size(unsigned char *buf, int width, int height)
{
  	datap = buf;
	getbyte();
	getbyte();
	readtables(M_SOF0);
	getword();
	getbyte();
        if (height != getword() || width != getword())
		return 0;
        return 1;
}

int jpeg_decode(unsigned char *buf, unsigned char *pic,
		int width, int height, int depth, struct jpeg_decdata *decdata)
{
	int i, j, m, tac, tdc;
	int mcusx, mcusy, mx, my;
	int max[6];

	if (!decdata || !buf || !pic)
		return -1;
	datap = buf;
	if (getbyte() != 0xff)
		return ERR_NO_SOI;
	if (getbyte() != M_SOI)
		return ERR_NO_SOI;
	if (readtables(M_SOF0))
		return ERR_BAD_TABLES;
	getword();
	i = getbyte();
	if (i != 8)
		return ERR_NOT_8BIT;
	if (((getword() + 15) & ~15) != height)
		return ERR_HEIGHT_MISMATCH;
	if (((getword() + 15) & ~15) != width)
		return ERR_WIDTH_MISMATCH;
	if ((height & 15) || (width & 15))
		return ERR_BAD_WIDTH_OR_HEIGHT;
	info.nc = getbyte();
	if (info.nc > MAXCOMP)
		return ERR_TOO_MANY_COMPPS;
	for (i = 0; i < info.nc; i++) {
		int h, v;
		comps[i].cid = getbyte();
		comps[i].hv = getbyte();
		v = comps[i].hv & 15;
		h = comps[i].hv >> 4;
		comps[i].tq = getbyte();
		if (h > 3 || v > 3)
			return ERR_ILLEGAL_HV;
		if (comps[i].tq > 3)
			return ERR_QUANT_TABLE_SELECTOR;
	}
	if (readtables(M_SOS))
		return ERR_BAD_TABLES;
	getword();
	info.ns = getbyte();
	if (info.ns != 3)
		return ERR_NOT_YCBCR_221111;
	for (i = 0; i < 3; i++) {
		dscans[i].cid = getbyte();
		tdc = getbyte();
		tac = tdc & 15;
		tdc >>= 4;
		if (tdc > 1 || tac > 1)
			return ERR_QUANT_TABLE_SELECTOR;
		for (j = 0; j < info.nc; j++)
			if (comps[j].cid == dscans[i].cid)
				break;
		if (j == info.nc)
			return ERR_UNKNOWN_CID_IN_SCAN;
		dscans[i].hv = comps[j].hv;
		dscans[i].tq = comps[j].tq;
		dscans[i].hudc.dhuff = dec_huffdc + tdc;
		dscans[i].huac.dhuff = dec_huffac + tac;
	}

	i = getbyte();
	j = getbyte();
	m = getbyte();

	if (i != 0 || j != 63 || m != 0)
		return ERR_NOT_SEQUENTIAL_DCT;

	if (dscans[0].cid != 1 || dscans[1].cid != 2 || dscans[2].cid != 3)
		return ERR_NOT_YCBCR_221111;

	if (dscans[0].hv != 0x22 || dscans[1].hv != 0x11 || dscans[2].hv != 0x11)
		return ERR_NOT_YCBCR_221111;

	mcusx = width >> 4;
	mcusy = height >> 4;


	idctqtab(quant[dscans[0].tq], decdata->dquant[0]);
	idctqtab(quant[dscans[1].tq], decdata->dquant[1]);
	idctqtab(quant[dscans[2].tq], decdata->dquant[2]);
	initcol(decdata->dquant);
	setinput(&glob_in, datap);

#if 0
	/* landing zone */
	img[len] = 0;
	img[len + 1] = 0xff;
	img[len + 2] = M_EOF;
#endif

	dec_initscans();

	dscans[0].next = 6 - 4;
	dscans[1].next = 6 - 4 - 1;
	dscans[2].next = 6 - 4 - 1 - 1;	/* 411 encoding */
	for (my = 0; my < mcusy; my++) {
		for (mx = 0; mx < mcusx; mx++) {
			if (info.dri && !--info.nm)
				if (dec_checkmarker())
					return ERR_WRONG_MARKER;

			decode_mcus(&glob_in, decdata->dcts, 6, dscans, max);
			idct(decdata->dcts, decdata->out, decdata->dquant[0], IFIX(128.5), max[0]);
			idct(decdata->dcts + 64, decdata->out + 64, decdata->dquant[0], IFIX(128.5), max[1]);
			idct(decdata->dcts + 128, decdata->out + 128, decdata->dquant[0], IFIX(128.5), max[2]);
			idct(decdata->dcts + 192, decdata->out + 192, decdata->dquant[0], IFIX(128.5), max[3]);
			idct(decdata->dcts + 256, decdata->out + 256, decdata->dquant[1], IFIX(0.5), max[4]);
			idct(decdata->dcts + 320, decdata->out + 320, decdata->dquant[2], IFIX(0.5), max[5]);

			switch (depth) {
			case 32:
				col221111_32(decdata->out, pic + (my * 16 * mcusx + mx) * 16 * 4, mcusx * 16 * 4);
				break;
			case 24:
				col221111(decdata->out, pic + (my * 16 * mcusx + mx) * 16 * 3, mcusx * 16 * 3);
				break;
			case 16:
				col221111_16(decdata->out, pic + (my * 16 * mcusx + mx) * (16 * 2), mcusx * (16 * 2));
				break;
			default:
				return ERR_DEPTH_MISMATCH;
				break;
			}
		}
	}

	m = dec_readmarker(&glob_in);
	if (m != M_EOI)
		return ERR_NO_EOI;

	return 0;
}

/****************************************************************/
/**************       huffman decoder             ***************/
/****************************************************************/

static int fillbits __P((struct in *, int, unsigned int));
static int dec_rec2
__P((struct in *, struct dec_hufftbl *, int *, int, int));

static void setinput(struct in *in, unsigned char *p)
{
	in->p = p;
	in->left = 0;
	in->bits = 0;
	in->marker = 0;
}

static int fillbits(struct in *in, int le, unsigned int bi)
{
	int b, m;

	if (in->marker) {
		if (le <= 16)
			in->bits = bi << 16, le += 16;
		return le;
	}
	while (le <= 24) {
		b = *in->p++;
		if (b == 0xff && (m = *in->p++) != 0) {
			if (m == M_EOF) {
				if (in->func && (m = in->func(in->data)) == 0)
					continue;
			}
			in->marker = m;
			if (le <= 16)
				bi = bi << 16, le += 16;
			break;
		}
		bi = bi << 8 | b;
		le += 8;
	}
	in->bits = bi;		/* tmp... 2 return values needed */
	return le;
}

static int dec_readmarker(struct in *in)
{
	int m;

	in->left = fillbits(in, in->left, in->bits);
	if ((m = in->marker) == 0)
		return 0;
	in->left = 0;
	in->marker = 0;
	return m;
}

#define LEBI_DCL	int le, bi
#define LEBI_GET(in)	(le = in->left, bi = in->bits)
#define LEBI_PUT(in)	(in->left = le, in->bits = bi)

#define GETBITS(in, n) (					\
  (le < (n) ? le = fillbits(in, le, bi), bi = in->bits : 0),	\
  (le -= (n)),							\
  bi >> le & ((1 << (n)) - 1)					\
)

#define UNGETBITS(in, n) (	\
  le += (n)			\
)


static int dec_rec2(struct in *in, struct dec_hufftbl *hu, int *runp, int c,
		int i)
{
	LEBI_DCL;

	LEBI_GET(in);
	if (i) {
		UNGETBITS(in, i & 127);
		*runp = i >> 8 & 15;
		i >>= 16;
	} else {
		for (i = DECBITS; (c = ((c << 1) | GETBITS(in, 1))) >= (hu->maxcode[i]); i++);
		if (i >= 16) {
			in->marker = M_BADHUFF;
			return 0;
		}
		i = hu->vals[hu->valptr[i] + c - hu->maxcode[i - 1] * 2];
		*runp = i >> 4;
		i &= 15;
	}
	if (i == 0) {		/* sigh, 0xf0 is 11 bit */
		LEBI_PUT(in);
		return 0;
	}
	/* receive part */
	c = GETBITS(in, i);
	if (c < (1 << (i - 1)))
		c += (-1 << i) + 1;
	LEBI_PUT(in);
	return c;
}

#define DEC_REC(in, hu, r, i)	 (	\
  r = GETBITS(in, DECBITS),		\
  i = hu->llvals[r],			\
  i & 128 ?				\
    (					\
      UNGETBITS(in, i & 127),		\
      r = i >> 8 & 15,			\
      i >> 16				\
    )					\
  :					\
    (					\
      LEBI_PUT(in),			\
      i = dec_rec2(in, hu, &r, r, i),	\
      LEBI_GET(in),			\
      i					\
    )					\
)

static void decode_mcus(struct in *in, int *dct, int n, struct scan *sc, int *maxp)
{
	struct dec_hufftbl *hu;
	int i, r, t;
	LEBI_DCL;

	memset(dct, 0, n * 64 * sizeof(*dct));
	LEBI_GET(in);
	while (n-- > 0) {
		hu = sc->hudc.dhuff;
		*dct++ = (sc->dc += DEC_REC(in, hu, r, t));

		hu = sc->huac.dhuff;
		i = 63;
		while (i > 0) {
			t = DEC_REC(in, hu, r, t);
			if (t == 0 && r == 0) {
				dct += i;
				break;
			}
			dct += r;
			*dct++ = t;
			i -= r + 1;
		}
		*maxp++ = 64 - i;
		if (n == sc->next)
			sc++;
	}
	LEBI_PUT(in);
}

static void dec_makehuff(struct dec_hufftbl *hu, int *hufflen, unsigned char *huffvals)
{
	int code, k, i, j, d, x, c, v;
	for (i = 0; i < (1 << DECBITS); i++)
		hu->llvals[i] = 0;

/*
 * llvals layout:
 *
 * value v already known, run r, backup u bits:
 *  vvvvvvvvvvvvvvvv 0000 rrrr 1 uuuuuuu
 * value unknown, size b bits, run r, backup u bits:
 *  000000000000bbbb 0000 rrrr 0 uuuuuuu
 * value and size unknown:
 *  0000000000000000 0000 0000 0 0000000
 */
	code = 0;
	k = 0;
	for (i = 0; i < 16; i++, code <<= 1) {	/* sizes */
		hu->valptr[i] = k;
		for (j = 0; j < hufflen[i]; j++) {
			hu->vals[k] = *huffvals++;
			if (i < DECBITS) {
				c = code << (DECBITS - 1 - i);
				v = hu->vals[k] & 0x0f;	/* size */
				for (d = 1 << (DECBITS - 1 - i); --d >= 0;) {
					if (v + i < DECBITS) {	/* both fit in table */
						x = d >> (DECBITS - 1 - v -
							  i);
						if (v && x < (1 << (v - 1)))
							x += (-1 << v) + 1;
						x = x << 16 | (hu-> vals[k] & 0xf0) << 4 |
							(DECBITS - (i + 1 + v)) | 128;
					} else
						x = v << 16 | (hu-> vals[k] & 0xf0) << 4 |
						        (DECBITS - (i + 1));
					hu->llvals[c | d] = x;
				}
			}
			code++;
			k++;
		}
		hu->maxcode[i] = code;
	}
	hu->maxcode[16] = 0x20000;	/* always terminate decode */
}

/****************************************************************/
/**************             idct                  ***************/
/****************************************************************/

#define ONE ((PREC)IFIX(1.))
#define S2  ((PREC)IFIX(0.382683432))
#define C2  ((PREC)IFIX(0.923879532))
#define C4  ((PREC)IFIX(0.707106781))

#define S22 ((PREC)IFIX(2 * 0.382683432))
#define C22 ((PREC)IFIX(2 * 0.923879532))
#define IC4 ((PREC)IFIX(1 / 0.707106781))

#define C3IC1 ((PREC)IFIX(0.847759065))	/* c3/c1 */
#define C5IC1 ((PREC)IFIX(0.566454497))	/* c5/c1 */
#define C7IC1 ((PREC)IFIX(0.198912367))	/* c7/c1 */

#define XPP(a,b) (t = a + b, b = a - b, a = t)
#define XMP(a,b) (t = a - b, b = a + b, a = t)
#define XPM(a,b) (t = a + b, b = b - a, a = t)

#define ROT(a,b,s,c) (	t = IMULT(a + b, s),	\
			a = IMULT(a, c - s) + t,	\
			b = IMULT(b, c + s) - t)

#define IDCT		\
(			\
  XPP(t0, t1),		\
  XMP(t2, t3),		\
  t2 = IMULT(t2, IC4) - t3,	\
  XPP(t0, t3),		\
  XPP(t1, t2),		\
  XMP(t4, t7),		\
  XPP(t5, t6),		\
  XMP(t5, t7),		\
  t5 = IMULT(t5, IC4),	\
  ROT(t4, t6, S22, C22),\
  t6 -= t7,		\
  t5 -= t6,		\
  t4 -= t5,		\
  XPP(t0, t7),		\
  XPP(t1, t6),		\
  XPP(t2, t5),		\
  XPP(t3, t4)		\
)

static unsigned char zig2[64] = {
	0, 2, 3, 9, 10, 20, 21, 35,
	14, 16, 25, 31, 39, 46, 50, 57,
	5, 7, 12, 18, 23, 33, 37, 48,
	27, 29, 41, 44, 52, 55, 59, 62,
	15, 26, 30, 40, 45, 51, 56, 58,
	1, 4, 8, 11, 19, 22, 34, 36,
	28, 42, 43, 53, 54, 60, 61, 63,
	6, 13, 17, 24, 32, 38, 47, 49
};

void idct(int *in, int *out, PREC *lquant, PREC off, int max)
{
	PREC t0, t1, t2, t3, t4, t5, t6, t7, t;
	PREC tmp[64], *tmpp;
	int i, j;
	unsigned char *zig2p;

	t0 = off;
	if (max == 1) {
		t0 += in[0] * lquant[0];
		for (i = 0; i < 64; i++)
			out[i] = ITOINT(t0);
		return;
	}
	zig2p = zig2;
	tmpp = tmp;
	for (i = 0; i < 8; i++) {
		j = *zig2p++;
		t0 += in[j] * lquant[j];
		j = *zig2p++;
		t5 = in[j] * lquant[j];
		j = *zig2p++;
		t2 = in[j] * lquant[j];
		j = *zig2p++;
		t7 = in[j] * lquant[j];
		j = *zig2p++;
		t1 = in[j] * lquant[j];
		j = *zig2p++;
		t4 = in[j] * lquant[j];
		j = *zig2p++;
		t3 = in[j] * lquant[j];
		j = *zig2p++;
		t6 = in[j] * lquant[j];
		IDCT;
		tmpp[0 * 8] = t0;
		tmpp[1 * 8] = t1;
		tmpp[2 * 8] = t2;
		tmpp[3 * 8] = t3;
		tmpp[4 * 8] = t4;
		tmpp[5 * 8] = t5;
		tmpp[6 * 8] = t6;
		tmpp[7 * 8] = t7;
		tmpp++;
		t0 = 0;
	}
	for (i = 0; i < 8; i++) {
		t0 = tmp[8 * i + 0];
		t1 = tmp[8 * i + 1];
		t2 = tmp[8 * i + 2];
		t3 = tmp[8 * i + 3];
		t4 = tmp[8 * i + 4];
		t5 = tmp[8 * i + 5];
		t6 = tmp[8 * i + 6];
		t7 = tmp[8 * i + 7];
		IDCT;
		out[8 * i + 0] = ITOINT(t0);
		out[8 * i + 1] = ITOINT(t1);
		out[8 * i + 2] = ITOINT(t2);
		out[8 * i + 3] = ITOINT(t3);
		out[8 * i + 4] = ITOINT(t4);
		out[8 * i + 5] = ITOINT(t5);
		out[8 * i + 6] = ITOINT(t6);
		out[8 * i + 7] = ITOINT(t7);
	}
}

static unsigned char zig[64] = {
	0, 1, 5, 6, 14, 15, 27, 28,
	2, 4, 7, 13, 16, 26, 29, 42,
	3, 8, 12, 17, 25, 30, 41, 43,
	9, 11, 18, 24, 31, 40, 44, 53,
	10, 19, 23, 32, 39, 45, 52, 54,
	20, 22, 33, 38, 46, 51, 55, 60,
	21, 34, 37, 47, 50, 56, 59, 61,
	35, 36, 48, 49, 57, 58, 62, 63
};

static PREC aaidct[8] = {
	IFIX(0.3535533906), IFIX(0.4903926402),
	IFIX(0.4619397663), IFIX(0.4157348062),
	IFIX(0.3535533906), IFIX(0.2777851165),
	IFIX(0.1913417162), IFIX(0.0975451610)
};


static void idctqtab(unsigned char *qin, PREC *qout)
{
	int i, j;

	for (i = 0; i < 8; i++)
		for (j = 0; j < 8; j++)
			qout[zig[i * 8 + j]] = qin[zig[i * 8 + j]] *
			  			IMULT(aaidct[i], aaidct[j]);
}

static void scaleidctqtab(PREC *q, PREC sc)
{
	int i;

	for (i = 0; i < 64; i++)
		q[i] = IMULT(q[i], sc);
}

/****************************************************************/
/**************          color decoder            ***************/
/****************************************************************/

#define ROUND

/*
 * YCbCr Color transformation:
 *
 * y:0..255   Cb:-128..127   Cr:-128..127
 *
 *      R = Y                + 1.40200 * Cr
 *      G = Y - 0.34414 * Cb - 0.71414 * Cr
 *      B = Y + 1.77200 * Cb
 *
 * =>
 *      Cr *= 1.40200;
 *      Cb *= 1.77200;
 *      Cg = 0.19421 * Cb + .50937 * Cr;
 *      R = Y + Cr;
 *      G = Y - Cg;
 *      B = Y + Cb;
 *
 * =>
 *      Cg = (50 * Cb + 130 * Cr + 128) >> 8;
 */

static void initcol(PREC q[][64])
{
	scaleidctqtab(q[1], IFIX(1.77200));
	scaleidctqtab(q[2], IFIX(1.40200));
}

/* This is optimized for the stupid sun SUNWspro compiler. */
#define STORECLAMP(a,x)				\
(						\
  (a) = (x),					\
  (unsigned int)(x) >= 256 ? 			\
    ((a) = (x) < 0 ? 0 : 255)			\
  :						\
    0						\
)

#define CLAMP(x) ((unsigned int)(x) >= 256 ? ((x) < 0 ? 0 : 255) : (x))

#ifdef ROUND

#define CBCRCG(yin, xin)			\
(						\
  cb = outc[0 +yin*8+xin],			\
  cr = outc[64+yin*8+xin],			\
  cg = (50 * cb + 130 * cr + 128) >> 8		\
)

#else

#define CBCRCG(yin, xin)			\
(						\
  cb = outc[0 +yin*8+xin],			\
  cr = outc[64+yin*8+xin],			\
  cg = (3 * cb + 8 * cr) >> 4			\
)

#endif

#define PIC(yin, xin, p, xout)			\
(						\
  y = outy[(yin) * 8 + xin],			\
  STORECLAMP(p[(xout) * 3 + 0], y + cr),	\
  STORECLAMP(p[(xout) * 3 + 1], y - cg),	\
  STORECLAMP(p[(xout) * 3 + 2], y + cb)		\
)

#ifdef __LITTLE_ENDIAN
#define PIC_16(yin, xin, p, xout, add)		 \
(                                                \
  y = outy[(yin) * 8 + xin],                     \
  y = ((CLAMP(y + cr + add*2+1) & 0xf8) <<  8) | \
      ((CLAMP(y - cg + add    ) & 0xfc) <<  3) | \
      ((CLAMP(y + cb + add*2+1)       ) >>  3),  \
  p[(xout) * 2 + 0] = y & 0xff,                  \
  p[(xout) * 2 + 1] = y >> 8                     \
)
#else
#ifdef CONFIG_PPC
#define PIC_16(yin, xin, p, xout, add)		 \
(                                                \
  y = outy[(yin) * 8 + xin],                     \
  y = ((CLAMP(y + cr + add*2+1) & 0xf8) <<  7) | \
      ((CLAMP(y - cg + add*2+1) & 0xf8) <<  2) | \
      ((CLAMP(y + cb + add*2+1)       ) >>  3),  \
  p[(xout) * 2 + 0] = y >> 8,                    \
  p[(xout) * 2 + 1] = y & 0xff                   \
)
#else
#define PIC_16(yin, xin, p, xout, add)	 	 \
(                                                \
  y = outy[(yin) * 8 + xin],                     \
  y = ((CLAMP(y + cr + add*2+1) & 0xf8) <<  8) | \
      ((CLAMP(y - cg + add    ) & 0xfc) <<  3) | \
      ((CLAMP(y + cb + add*2+1)       ) >>  3),  \
  p[(xout) * 2 + 0] = y >> 8,                    \
  p[(xout) * 2 + 1] = y & 0xff                   \
)
#endif
#endif

#define PIC_32(yin, xin, p, xout)		\
(						\
  y = outy[(yin) * 8 + xin],			\
  STORECLAMP(p[(xout) * 4 + 0], y + cr),	\
  STORECLAMP(p[(xout) * 4 + 1], y - cg),	\
  STORECLAMP(p[(xout) * 4 + 2], y + cb),	\
  p[(xout) * 4 + 3] = 0				\
)

#define PIC221111(xin)						\
(								\
  CBCRCG(0, xin),						\
  PIC(xin / 4 * 8 + 0, (xin & 3) * 2 + 0, pic0, xin * 2 + 0),	\
  PIC(xin / 4 * 8 + 0, (xin & 3) * 2 + 1, pic0, xin * 2 + 1),	\
  PIC(xin / 4 * 8 + 1, (xin & 3) * 2 + 0, pic1, xin * 2 + 0),	\
  PIC(xin / 4 * 8 + 1, (xin & 3) * 2 + 1, pic1, xin * 2 + 1)	\
)

#define PIC221111_16(xin)                                               \
(                                                               	\
  CBCRCG(0, xin),                                               	\
  PIC_16(xin / 4 * 8 + 0, (xin & 3) * 2 + 0, pic0, xin * 2 + 0, 3),     \
  PIC_16(xin / 4 * 8 + 0, (xin & 3) * 2 + 1, pic0, xin * 2 + 1, 0),     \
  PIC_16(xin / 4 * 8 + 1, (xin & 3) * 2 + 0, pic1, xin * 2 + 0, 1),     \
  PIC_16(xin / 4 * 8 + 1, (xin & 3) * 2 + 1, pic1, xin * 2 + 1, 2)      \
)

#define PIC221111_32(xin)					\
(								\
  CBCRCG(0, xin),						\
  PIC_32(xin / 4 * 8 + 0, (xin & 3) * 2 + 0, pic0, xin * 2 + 0),\
  PIC_32(xin / 4 * 8 + 0, (xin & 3) * 2 + 1, pic0, xin * 2 + 1),\
  PIC_32(xin / 4 * 8 + 1, (xin & 3) * 2 + 0, pic1, xin * 2 + 0),\
  PIC_32(xin / 4 * 8 + 1, (xin & 3) * 2 + 1, pic1, xin * 2 + 1)	\
)

static void col221111(int *out, unsigned char *pic, int width)
{
	int i, j, k;
	unsigned char *pic0, *pic1;
	int *outy, *outc;
	int cr, cg, cb, y;

	pic0 = pic;
	pic1 = pic + width;
	outy = out;
	outc = out + 64 * 4;
	for (i = 2; i > 0; i--) {
		for (j = 4; j > 0; j--) {
			for (k = 0; k < 8; k++) {
				PIC221111(k);
			}
			outc += 8;
			outy += 16;
			pic0 += 2 * width;
			pic1 += 2 * width;
		}
		outy += 64 * 2 - 16 * 4;
	}
}

static void col221111_16(int *out, unsigned char *pic, int width)
{
	int i, j, k;
	unsigned char *pic0, *pic1;
	int *outy, *outc;
	int cr, cg, cb, y;

	pic0 = pic;
	pic1 = pic + width;
	outy = out;
	outc = out + 64 * 4;
	for (i = 2; i > 0; i--) {
		for (j = 4; j > 0; j--) {
			for (k = 0; k < 8; k++) {
			    PIC221111_16(k);
			}
			outc += 8;
			outy += 16;
			pic0 += 2 * width;
			pic1 += 2 * width;
		}
		outy += 64 * 2 - 16 * 4;
	}
}

static void col221111_32(int *out, unsigned char *pic, int width)
{
	int i, j, k;
	unsigned char *pic0, *pic1;
	int *outy, *outc;
	int cr, cg, cb, y;

	pic0 = pic;
	pic1 = pic + width;
	outy = out;
	outc = out + 64 * 4;
	for (i = 2; i > 0; i--) {
		for (j = 4; j > 0; j--) {
			for (k = 0; k < 8; k++) {
				PIC221111_32(k);
			}
			outc += 8;
			outy += 16;
			pic0 += 2 * width;
			pic1 += 2 * width;
		}
		outy += 64 * 2 - 16 * 4;
	}
}