aboutsummaryrefslogtreecommitdiffstats
path: root/libswscale/ppc/yuv2rgb_altivec.c
blob: 8aaa987e6234730b0f7eaddf94fe857e09abd742 (plain) (blame)
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
/*
 * AltiVec acceleration for colorspace conversion
 *
 * copyright (C) 2004 Marc Hoffman <marc.hoffman@analog.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
Convert I420 YV12 to RGB in various formats,
  it rejects images that are not in 420 formats,
  it rejects images that don't have widths of multiples of 16,
  it rejects images that don't have heights of multiples of 2.
Reject defers to C simulation code.

Lots of optimizations to be done here.

1. Need to fix saturation code. I just couldn't get it to fly with packs
   and adds, so we currently use max/min to clip.

2. The inefficient use of chroma loading needs a bit of brushing up.

3. Analysis of pipeline stalls needs to be done. Use shark to identify
   pipeline stalls.


MODIFIED to calculate coeffs from currently selected color space.
MODIFIED core to be a macro where you specify the output format.
ADDED UYVY conversion which is never called due to some thing in swscale.
CORRECTED algorithim selection to be strict on input formats.
ADDED runtime detection of AltiVec.

ADDED altivec_yuv2packedX vertical scl + RGB converter

March 27,2004
PERFORMANCE ANALYSIS

The C version uses 25% of the processor or ~250Mips for D1 video rawvideo
used as test.
The AltiVec version uses 10% of the processor or ~100Mips for D1 video
same sequence.

720 * 480 * 30  ~10MPS

so we have roughly 10 clocks per pixel. This is too high, something has
to be wrong.

OPTIMIZED clip codes to utilize vec_max and vec_packs removing the
need for vec_min.

OPTIMIZED DST OUTPUT cache/DMA controls. We are pretty much guaranteed to have
the input video frame, it was just decompressed so it probably resides in L1
caches. However, we are creating the output video stream. This needs to use the
DSTST instruction to optimize for the cache. We couple this with the fact that
we are not going to be visiting the input buffer again so we mark it Least
Recently Used. This shaves 25% of the processor cycles off.

Now memcpy is the largest mips consumer in the system, probably due
to the inefficient X11 stuff.

GL libraries seem to be very slow on this machine 1.33Ghz PB running
Jaguar, this is not the case for my 1Ghz PB.  I thought it might be
a versioning issue, however I have libGL.1.2.dylib for both
machines. (We need to figure this out now.)

GL2 libraries work now with patch for RGB32.

NOTE: quartz vo driver ARGB32_to_RGB24 consumes 30% of the processor.

Integrated luma prescaling adjustment for saturation/contrast/brightness
adjustment.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <assert.h>
#include "config.h"
#include "libswscale/rgb2rgb.h"
#include "libswscale/swscale.h"
#include "libswscale/swscale_internal.h"
#include "libavutil/cpu.h"
#include "libavutil/pixdesc.h"

#undef PROFILE_THE_BEAST
#undef INC_SCALING

typedef unsigned char ubyte;
typedef signed char   sbyte;


/* RGB interleaver, 16 planar pels 8-bit samples per channel in
   homogeneous vector registers x0,x1,x2 are interleaved with the
   following technique:

      o0 = vec_mergeh (x0,x1);
      o1 = vec_perm (o0, x2, perm_rgb_0);
      o2 = vec_perm (o0, x2, perm_rgb_1);
      o3 = vec_mergel (x0,x1);
      o4 = vec_perm (o3,o2,perm_rgb_2);
      o5 = vec_perm (o3,o2,perm_rgb_3);

  perm_rgb_0:   o0(RG).h v1(B) --> o1*
              0   1  2   3   4
             rgbr|gbrg|brgb|rgbr
             0010 0100 1001 0010
             0102 3145 2673 894A

  perm_rgb_1:   o0(RG).h v1(B) --> o2
              0   1  2   3   4
             gbrg|brgb|bbbb|bbbb
             0100 1001 1111 1111
             B5CD 6EF7 89AB CDEF

  perm_rgb_2:   o3(RG).l o2(rgbB.l) --> o4*
              0   1  2   3   4
             gbrg|brgb|rgbr|gbrg
             1111 1111 0010 0100
             89AB CDEF 0182 3945

  perm_rgb_2:   o3(RG).l o2(rgbB.l) ---> o5*
              0   1  2   3   4
             brgb|rgbr|gbrg|brgb
             1001 0010 0100 1001
             a67b 89cA BdCD eEFf

*/
static
const vector unsigned char
  perm_rgb_0 = {0x00,0x01,0x10,0x02,0x03,0x11,0x04,0x05,
                0x12,0x06,0x07,0x13,0x08,0x09,0x14,0x0a},
  perm_rgb_1 = {0x0b,0x15,0x0c,0x0d,0x16,0x0e,0x0f,0x17,
                0x18,0x19,0x1a,0x1b,0x1c,0x1d,0x1e,0x1f},
  perm_rgb_2 = {0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17,
                0x00,0x01,0x18,0x02,0x03,0x19,0x04,0x05},
  perm_rgb_3 = {0x1a,0x06,0x07,0x1b,0x08,0x09,0x1c,0x0a,
                0x0b,0x1d,0x0c,0x0d,0x1e,0x0e,0x0f,0x1f};

#define vec_merge3(x2,x1,x0,y0,y1,y2)       \
do {                                        \
    __typeof__(x0) o0,o2,o3;                \
        o0 = vec_mergeh (x0,x1);            \
        y0 = vec_perm (o0, x2, perm_rgb_0); \
        o2 = vec_perm (o0, x2, perm_rgb_1); \
        o3 = vec_mergel (x0,x1);            \
        y1 = vec_perm (o3,o2,perm_rgb_2);   \
        y2 = vec_perm (o3,o2,perm_rgb_3);   \
} while(0)

#define vec_mstbgr24(x0,x1,x2,ptr)      \
do {                                    \
    __typeof__(x0) _0,_1,_2;            \
    vec_merge3 (x0,x1,x2,_0,_1,_2);     \
    vec_st (_0, 0, ptr++);              \
    vec_st (_1, 0, ptr++);              \
    vec_st (_2, 0, ptr++);              \
}  while (0)

#define vec_mstrgb24(x0,x1,x2,ptr)      \
do {                                    \
    __typeof__(x0) _0,_1,_2;            \
    vec_merge3 (x2,x1,x0,_0,_1,_2);     \
    vec_st (_0, 0, ptr++);              \
    vec_st (_1, 0, ptr++);              \
    vec_st (_2, 0, ptr++);              \
}  while (0)

/* pack the pixels in rgb0 format
   msb R
   lsb 0
*/
#define vec_mstrgb32(T,x0,x1,x2,x3,ptr)                                       \
do {                                                                          \
    T _0,_1,_2,_3;                                                            \
    _0 = vec_mergeh (x0,x1);                                                  \
    _1 = vec_mergeh (x2,x3);                                                  \
    _2 = (T)vec_mergeh ((vector unsigned short)_0,(vector unsigned short)_1); \
    _3 = (T)vec_mergel ((vector unsigned short)_0,(vector unsigned short)_1); \
    vec_st (_2, 0*16, (T *)ptr);                                              \
    vec_st (_3, 1*16, (T *)ptr);                                              \
    _0 = vec_mergel (x0,x1);                                                  \
    _1 = vec_mergel (x2,x3);                                                  \
    _2 = (T)vec_mergeh ((vector unsigned short)_0,(vector unsigned short)_1); \
    _3 = (T)vec_mergel ((vector unsigned short)_0,(vector unsigned short)_1); \
    vec_st (_2, 2*16, (T *)ptr);                                              \
    vec_st (_3, 3*16, (T *)ptr);                                              \
    ptr += 4;                                                                 \
}  while (0)

/*

  | 1     0       1.4021   | | Y |
  | 1    -0.3441 -0.7142   |x| Cb|
  | 1     1.7718  0        | | Cr|


  Y:      [-128 127]
  Cb/Cr : [-128 127]

  typical yuv conversion work on Y: 0-255 this version has been optimized for jpeg decode.

*/




#define vec_unh(x) \
    (vector signed short) \
        vec_perm(x,(__typeof__(x)){0}, \
                 ((vector unsigned char){0x10,0x00,0x10,0x01,0x10,0x02,0x10,0x03,\
                                         0x10,0x04,0x10,0x05,0x10,0x06,0x10,0x07}))
#define vec_unl(x) \
    (vector signed short) \
        vec_perm(x,(__typeof__(x)){0}, \
                 ((vector unsigned char){0x10,0x08,0x10,0x09,0x10,0x0A,0x10,0x0B,\
                                         0x10,0x0C,0x10,0x0D,0x10,0x0E,0x10,0x0F}))

#define vec_clip_s16(x) \
    vec_max (vec_min (x, ((vector signed short){235,235,235,235,235,235,235,235})), \
                         ((vector signed short){ 16, 16, 16, 16, 16, 16, 16, 16}))

#define vec_packclp(x,y) \
    (vector unsigned char)vec_packs \
        ((vector unsigned short)vec_max (x,((vector signed short) {0})), \
         (vector unsigned short)vec_max (y,((vector signed short) {0})))

//#define out_pixels(a,b,c,ptr) vec_mstrgb32(__typeof__(a),((__typeof__ (a)){255}),a,a,a,ptr)


static inline void cvtyuvtoRGB (SwsContext *c,
                                vector signed short Y, vector signed short U, vector signed short V,
                                vector signed short *R, vector signed short *G, vector signed short *B)
{
    vector signed   short vx,ux,uvx;

    Y = vec_mradds (Y, c->CY, c->OY);
    U  = vec_sub (U,(vector signed short)
                    vec_splat((vector signed short){128},0));
    V  = vec_sub (V,(vector signed short)
                    vec_splat((vector signed short){128},0));

    //   ux  = (CBU*(u<<c->CSHIFT)+0x4000)>>15;
    ux = vec_sl (U, c->CSHIFT);
    *B = vec_mradds (ux, c->CBU, Y);

    // vx  = (CRV*(v<<c->CSHIFT)+0x4000)>>15;
    vx = vec_sl (V, c->CSHIFT);
    *R = vec_mradds (vx, c->CRV, Y);

    // uvx = ((CGU*u) + (CGV*v))>>15;
    uvx = vec_mradds (U, c->CGU, Y);
    *G  = vec_mradds (V, c->CGV, uvx);
}


/*
  ------------------------------------------------------------------------------
  CS converters
  ------------------------------------------------------------------------------
*/


#define DEFCSP420_CVT(name,out_pixels)                                  \
static int altivec_##name (SwsContext *c,                               \
                           const unsigned char **in, int *instrides,    \
                           int srcSliceY,        int srcSliceH,         \
                           unsigned char **oplanes, int *outstrides)    \
{                                                                       \
    int w = c->srcW;                                                    \
    int h = srcSliceH;                                                  \
    int i,j;                                                            \
    int instrides_scl[3];                                               \
    vector unsigned char y0,y1;                                         \
                                                                        \
    vector signed char  u,v;                                            \
                                                                        \
    vector signed short Y0,Y1,Y2,Y3;                                    \
    vector signed short U,V;                                            \
    vector signed short vx,ux,uvx;                                      \
    vector signed short vx0,ux0,uvx0;                                   \
    vector signed short vx1,ux1,uvx1;                                   \
    vector signed short R0,G0,B0;                                       \
    vector signed short R1,G1,B1;                                       \
    vector unsigned char R,G,B;                                         \
                                                                        \
    const vector unsigned char *y1ivP, *y2ivP, *uivP, *vivP;            \
    vector unsigned char align_perm;                                    \
                                                                        \
    vector signed short                                                 \
        lCY  = c->CY,                                                   \
        lOY  = c->OY,                                                   \
        lCRV = c->CRV,                                                  \
        lCBU = c->CBU,                                                  \
        lCGU = c->CGU,                                                  \
        lCGV = c->CGV;                                                  \
                                                                        \
    vector unsigned short lCSHIFT = c->CSHIFT;                          \
                                                                        \
    const ubyte *y1i   = in[0];                                         \
    const ubyte *y2i   = in[0]+instrides[0];                            \
    const ubyte *ui    = in[1];                                         \
    const ubyte *vi    = in[2];                                         \
                                                                        \
    vector unsigned char *oute                                          \
        = (vector unsigned char *)                                      \
            (oplanes[0]+srcSliceY*outstrides[0]);                       \
    vector unsigned char *outo                                          \
        = (vector unsigned char *)                                      \
            (oplanes[0]+srcSliceY*outstrides[0]+outstrides[0]);         \
                                                                        \
                                                                        \
    instrides_scl[0] = instrides[0]*2-w;  /* the loop moves y{1,2}i by w */ \
    instrides_scl[1] = instrides[1]-w/2;  /* the loop moves ui by w/2 */    \
    instrides_scl[2] = instrides[2]-w/2;  /* the loop moves vi by w/2 */    \
                                                                        \
                                                                        \
    for (i=0;i<h/2;i++) {                                               \
        vec_dstst (outo, (0x02000002|(((w*3+32)/32)<<16)), 0);          \
        vec_dstst (oute, (0x02000002|(((w*3+32)/32)<<16)), 1);          \
                                                                        \
        for (j=0;j<w/16;j++) {                                          \
                                                                        \
            y1ivP = (const vector unsigned char *)y1i;                  \
            y2ivP = (const vector unsigned char *)y2i;                  \
            uivP  = (const vector unsigned char *)ui;                   \
            vivP  = (const vector unsigned char *)vi;                   \
                                                                        \
            align_perm = vec_lvsl (0, y1i);                             \
            y0 = (vector unsigned char)                                 \
                 vec_perm (y1ivP[0], y1ivP[1], align_perm);             \
                                                                        \
            align_perm = vec_lvsl (0, y2i);                             \
            y1 = (vector unsigned char)                                 \
                 vec_perm (y2ivP[0], y2ivP[1], align_perm);             \
                                                                        \
            align_perm = vec_lvsl (0, ui);                              \
            u = (vector signed char)                                    \
                vec_perm (uivP[0], uivP[1], align_perm);                \
                                                                        \
            align_perm = vec_lvsl (0, vi);                              \
            v = (vector signed char)                                    \
                vec_perm (vivP[0], vivP[1], align_perm);                \
                                                                        \
            u  = (vector signed char)                                   \
                 vec_sub (u,(vector signed char)                        \
                          vec_splat((vector signed char){128},0));      \
            v  = (vector signed char)                                   \
                 vec_sub (v,(vector signed char)                        \
                          vec_splat((vector signed char){128},0));      \
                                                                        \
            U  = vec_unpackh (u);                                       \
            V  = vec_unpackh (v);                                       \
                                                                        \
                                                                        \
            Y0 = vec_unh (y0);                                          \
            Y1 = vec_unl (y0);                                          \
            Y2 = vec_unh (y1);                                          \
            Y3 = vec_unl (y1);                                          \
                                                                        \
            Y0 = vec_mradds (Y0, lCY, lOY);                             \
            Y1 = vec_mradds (Y1, lCY, lOY);                             \
            Y2 = vec_mradds (Y2, lCY, lOY);                             \
            Y3 = vec_mradds (Y3, lCY, lOY);                             \
                                                                        \
            /*   ux  = (CBU*(u<<CSHIFT)+0x4000)>>15 */                  \
            ux = vec_sl (U, lCSHIFT);                                   \
            ux = vec_mradds (ux, lCBU, (vector signed short){0});       \
            ux0  = vec_mergeh (ux,ux);                                  \
            ux1  = vec_mergel (ux,ux);                                  \
                                                                        \
            /* vx  = (CRV*(v<<CSHIFT)+0x4000)>>15;        */            \
            vx = vec_sl (V, lCSHIFT);                                   \
            vx = vec_mradds (vx, lCRV, (vector signed short){0});       \
            vx0  = vec_mergeh (vx,vx);                                  \
            vx1  = vec_mergel (vx,vx);                                  \
                                                                        \
            /* uvx = ((CGU*u) + (CGV*v))>>15 */                         \
            uvx = vec_mradds (U, lCGU, (vector signed short){0});       \
            uvx = vec_mradds (V, lCGV, uvx);                            \
            uvx0 = vec_mergeh (uvx,uvx);                                \
            uvx1 = vec_mergel (uvx,uvx);                                \
                                                                        \
            R0 = vec_add (Y0,vx0);                                      \
            G0 = vec_add (Y0,uvx0);                                     \
            B0 = vec_add (Y0,ux0);                                      \
            R1 = vec_add (Y1,vx1);                                      \
            G1 = vec_add (Y1,uvx1);                                     \
            B1 = vec_add (Y1,ux1);                                      \
                                                                        \
            R  = vec_packclp (R0,R1);                                   \
            G  = vec_packclp (G0,G1);                                   \
            B  = vec_packclp (B0,B1);                                   \
                                                                        \
            out_pixels(R,G,B,oute);                                     \
                                                                        \
            R0 = vec_add (Y2,vx0);                                      \
            G0 = vec_add (Y2,uvx0);                                     \
            B0 = vec_add (Y2,ux0);                                      \
            R1 = vec_add (Y3,vx1);                                      \
            G1 = vec_add (Y3,uvx1);                                     \
            B1 = vec_add (Y3,ux1);                                      \
            R  = vec_packclp (R0,R1);                                   \
            G  = vec_packclp (G0,G1);                                   \
            B  = vec_packclp (B0,B1);                                   \
                                                                        \
                                                                        \
            out_pixels(R,G,B,outo);                                     \
                                                                        \
            y1i  += 16;                                                 \
            y2i  += 16;                                                 \
            ui   += 8;                                                  \
            vi   += 8;                                                  \
                                                                        \
        }                                                               \
                                                                        \
        outo  += (outstrides[0])>>4;                                    \
        oute  += (outstrides[0])>>4;                                    \
                                                                        \
        ui    += instrides_scl[1];                                      \
        vi    += instrides_scl[2];                                      \
        y1i   += instrides_scl[0];                                      \
        y2i   += instrides_scl[0];                                      \
    }                                                                   \
    return srcSliceH;                                                   \
}


#define out_abgr(a,b,c,ptr)  vec_mstrgb32(__typeof__(a),((__typeof__ (a)){255}),c,b,a,ptr)
#define out_bgra(a,b,c,ptr)  vec_mstrgb32(__typeof__(a),c,b,a,((__typeof__ (a)){255}),ptr)
#define out_rgba(a,b,c,ptr)  vec_mstrgb32(__typeof__(a),a,b,c,((__typeof__ (a)){255}),ptr)
#define out_argb(a,b,c,ptr)  vec_mstrgb32(__typeof__(a),((__typeof__ (a)){255}),a,b,c,ptr)
#define out_rgb24(a,b,c,ptr) vec_mstrgb24(a,b,c,ptr)
#define out_bgr24(a,b,c,ptr) vec_mstbgr24(a,b,c,ptr)

DEFCSP420_CVT (yuv2_abgr, out_abgr)
DEFCSP420_CVT (yuv2_bgra, out_bgra)
DEFCSP420_CVT (yuv2_rgba, out_rgba)
DEFCSP420_CVT (yuv2_argb, out_argb)
DEFCSP420_CVT (yuv2_rgb24,  out_rgb24)
DEFCSP420_CVT (yuv2_bgr24,  out_bgr24)


// uyvy|uyvy|uyvy|uyvy
// 0123 4567 89ab cdef
static
const vector unsigned char
    demux_u = {0x10,0x00,0x10,0x00,
               0x10,0x04,0x10,0x04,
               0x10,0x08,0x10,0x08,
               0x10,0x0c,0x10,0x0c},
    demux_v = {0x10,0x02,0x10,0x02,
               0x10,0x06,0x10,0x06,
               0x10,0x0A,0x10,0x0A,
               0x10,0x0E,0x10,0x0E},
    demux_y = {0x10,0x01,0x10,0x03,
               0x10,0x05,0x10,0x07,
               0x10,0x09,0x10,0x0B,
               0x10,0x0D,0x10,0x0F};

/*
  this is so I can play live CCIR raw video
*/
static int altivec_uyvy_rgb32 (SwsContext *c,
                               const unsigned char **in, int *instrides,
                               int srcSliceY,        int srcSliceH,
                               unsigned char **oplanes, int *outstrides)
{
    int w = c->srcW;
    int h = srcSliceH;
    int i,j;
    vector unsigned char uyvy;
    vector signed   short Y,U,V;
    vector signed   short R0,G0,B0,R1,G1,B1;
    vector unsigned char  R,G,B;
    vector unsigned char *out;
    const ubyte *img;

    img = in[0];
    out = (vector unsigned char *)(oplanes[0]+srcSliceY*outstrides[0]);

    for (i=0;i<h;i++) {
        for (j=0;j<w/16;j++) {
            uyvy = vec_ld (0, img);
            U = (vector signed short)
                vec_perm (uyvy, (vector unsigned char){0}, demux_u);

            V = (vector signed short)
                vec_perm (uyvy, (vector unsigned char){0}, demux_v);

            Y = (vector signed short)
                vec_perm (uyvy, (vector unsigned char){0}, demux_y);

            cvtyuvtoRGB (c, Y,U,V,&R0,&G0,&B0);

            uyvy = vec_ld (16, img);
            U = (vector signed short)
                vec_perm (uyvy, (vector unsigned char){0}, demux_u);

            V = (vector signed short)
                vec_perm (uyvy, (vector unsigned char){0}, demux_v);

            Y = (vector signed short)
                vec_perm (uyvy, (vector unsigned char){0}, demux_y);

            cvtyuvtoRGB (c, Y,U,V,&R1,&G1,&B1);

            R  = vec_packclp (R0,R1);
            G  = vec_packclp (G0,G1);
            B  = vec_packclp (B0,B1);

            //      vec_mstbgr24 (R,G,B, out);
            out_rgba (R,G,B,out);

            img += 32;
        }
    }
    return srcSliceH;
}



/* Ok currently the acceleration routine only supports
   inputs of widths a multiple of 16
   and heights a multiple 2

   So we just fall back to the C codes for this.
*/
SwsFunc ff_yuv2rgb_init_altivec(SwsContext *c)
{
    if (!(av_get_cpu_flags() & AV_CPU_FLAG_ALTIVEC))
        return NULL;

    /*
      and this seems not to matter too much I tried a bunch of
      videos with abnormal widths and MPlayer crashes elsewhere.
      mplayer -vo x11 -rawvideo on:w=350:h=240 raw-350x240.eyuv
      boom with X11 bad match.

    */
    if ((c->srcW & 0xf) != 0)    return NULL;

    switch (c->srcFormat) {
    case PIX_FMT_YUV410P:
    case PIX_FMT_YUV420P:
    /*case IMGFMT_CLPL:        ??? */
    case PIX_FMT_GRAY8:
    case PIX_FMT_NV12:
    case PIX_FMT_NV21:
        if ((c->srcH & 0x1) != 0)
            return NULL;

        switch(c->dstFormat) {
        case PIX_FMT_RGB24:
            av_log(c, AV_LOG_WARNING, "ALTIVEC: Color Space RGB24\n");
            return altivec_yuv2_rgb24;
        case PIX_FMT_BGR24:
            av_log(c, AV_LOG_WARNING, "ALTIVEC: Color Space BGR24\n");
            return altivec_yuv2_bgr24;
        case PIX_FMT_ARGB:
            av_log(c, AV_LOG_WARNING, "ALTIVEC: Color Space ARGB\n");
            return altivec_yuv2_argb;
        case PIX_FMT_ABGR:
            av_log(c, AV_LOG_WARNING, "ALTIVEC: Color Space ABGR\n");
            return altivec_yuv2_abgr;
        case PIX_FMT_RGBA:
            av_log(c, AV_LOG_WARNING, "ALTIVEC: Color Space RGBA\n");
            return altivec_yuv2_rgba;
        case PIX_FMT_BGRA:
            av_log(c, AV_LOG_WARNING, "ALTIVEC: Color Space BGRA\n");
            return altivec_yuv2_bgra;
        default: return NULL;
        }
        break;

    case PIX_FMT_UYVY422:
        switch(c->dstFormat) {
        case PIX_FMT_BGR32:
            av_log(c, AV_LOG_WARNING, "ALTIVEC: Color Space UYVY -> RGB32\n");
            return altivec_uyvy_rgb32;
        default: return NULL;
        }
        break;

    }
    return NULL;
}

void ff_yuv2rgb_init_tables_altivec(SwsContext *c, const int inv_table[4], int brightness, int contrast, int saturation)
{
    union {
        DECLARE_ALIGNED(16, signed short, tmp)[8];
        vector signed short vec;
    } buf;

    buf.tmp[0] =  ((0xffffLL) * contrast>>8)>>9;                        //cy
    buf.tmp[1] =  -256*brightness;                                      //oy
    buf.tmp[2] =  (inv_table[0]>>3) *(contrast>>16)*(saturation>>16);   //crv
    buf.tmp[3] =  (inv_table[1]>>3) *(contrast>>16)*(saturation>>16);   //cbu
    buf.tmp[4] = -((inv_table[2]>>1)*(contrast>>16)*(saturation>>16));  //cgu
    buf.tmp[5] = -((inv_table[3]>>1)*(contrast>>16)*(saturation>>16));  //cgv


    c->CSHIFT = (vector unsigned short)vec_splat_u16(2);
    c->CY   = vec_splat ((vector signed short)buf.vec, 0);
    c->OY   = vec_splat ((vector signed short)buf.vec, 1);
    c->CRV  = vec_splat ((vector signed short)buf.vec, 2);
    c->CBU  = vec_splat ((vector signed short)buf.vec, 3);
    c->CGU  = vec_splat ((vector signed short)buf.vec, 4);
    c->CGV  = vec_splat ((vector signed short)buf.vec, 5);
    return;
}


void
ff_yuv2packedX_altivec(SwsContext *c, const int16_t *lumFilter,
                       const int16_t **lumSrc, int lumFilterSize,
                       const int16_t *chrFilter, const int16_t **chrUSrc,
                       const int16_t **chrVSrc, int chrFilterSize,
                       uint8_t *dest, int dstW, int dstY)
{
    int i,j;
    vector signed short X,X0,X1,Y0,U0,V0,Y1,U1,V1,U,V;
    vector signed short R0,G0,B0,R1,G1,B1;

    vector unsigned char R,G,B;
    vector unsigned char *out,*nout;

    vector signed short   RND = vec_splat_s16(1<<3);
    vector unsigned short SCL = vec_splat_u16(4);
    DECLARE_ALIGNED(16, unsigned int, scratch)[16];

    vector signed short *YCoeffs, *CCoeffs;

    YCoeffs = c->vYCoeffsBank+dstY*lumFilterSize;
    CCoeffs = c->vCCoeffsBank+dstY*chrFilterSize;

    out = (vector unsigned char *)dest;

    for (i=0; i<dstW; i+=16) {
        Y0 = RND;
        Y1 = RND;
        /* extract 16 coeffs from lumSrc */
        for (j=0; j<lumFilterSize; j++) {
            X0 = vec_ld (0,  &lumSrc[j][i]);
            X1 = vec_ld (16, &lumSrc[j][i]);
            Y0 = vec_mradds (X0, YCoeffs[j], Y0);
            Y1 = vec_mradds (X1, YCoeffs[j], Y1);
        }

        U = RND;
        V = RND;
        /* extract 8 coeffs from U,V */
        for (j=0; j<chrFilterSize; j++) {
            X  = vec_ld (0, &chrUSrc[j][i/2]);
            U  = vec_mradds (X, CCoeffs[j], U);
            X  = vec_ld (0, &chrVSrc[j][i/2]);
            V  = vec_mradds (X, CCoeffs[j], V);
        }

        /* scale and clip signals */
        Y0 = vec_sra (Y0, SCL);
        Y1 = vec_sra (Y1, SCL);
        U  = vec_sra (U,  SCL);
        V  = vec_sra (V,  SCL);

        Y0 = vec_clip_s16 (Y0);
        Y1 = vec_clip_s16 (Y1);
        U  = vec_clip_s16 (U);
        V  = vec_clip_s16 (V);

        /* now we have
          Y0= y0 y1 y2 y3 y4 y5 y6 y7     Y1= y8 y9 y10 y11 y12 y13 y14 y15
          U= u0 u1 u2 u3 u4 u5 u6 u7      V= v0 v1 v2 v3 v4 v5 v6 v7

          Y0= y0 y1 y2 y3 y4 y5 y6 y7    Y1= y8 y9 y10 y11 y12 y13 y14 y15
          U0= u0 u0 u1 u1 u2 u2 u3 u3    U1= u4 u4 u5 u5 u6 u6 u7 u7
          V0= v0 v0 v1 v1 v2 v2 v3 v3    V1= v4 v4 v5 v5 v6 v6 v7 v7
        */

        U0 = vec_mergeh (U,U);
        V0 = vec_mergeh (V,V);

        U1 = vec_mergel (U,U);
        V1 = vec_mergel (V,V);

        cvtyuvtoRGB (c, Y0,U0,V0,&R0,&G0,&B0);
        cvtyuvtoRGB (c, Y1,U1,V1,&R1,&G1,&B1);

        R  = vec_packclp (R0,R1);
        G  = vec_packclp (G0,G1);
        B  = vec_packclp (B0,B1);

        switch(c->dstFormat) {
        case PIX_FMT_ABGR:  out_abgr  (R,G,B,out); break;
        case PIX_FMT_BGRA:  out_bgra  (R,G,B,out); break;
        case PIX_FMT_RGBA:  out_rgba  (R,G,B,out); break;
        case PIX_FMT_ARGB:  out_argb  (R,G,B,out); break;
        case PIX_FMT_RGB24: out_rgb24 (R,G,B,out); break;
        case PIX_FMT_BGR24: out_bgr24 (R,G,B,out); break;
        default:
            {
                /* If this is reached, the caller should have called yuv2packedXinC
                   instead. */
                static int printed_error_message;
                if (!printed_error_message) {
                    av_log(c, AV_LOG_ERROR, "altivec_yuv2packedX doesn't support %s output\n",
                           av_get_pix_fmt_name(c->dstFormat));
                    printed_error_message=1;
                }
                return;
            }
        }
    }

    if (i < dstW) {
        i -= 16;

        Y0 = RND;
        Y1 = RND;
        /* extract 16 coeffs from lumSrc */
        for (j=0; j<lumFilterSize; j++) {
            X0 = vec_ld (0,  &lumSrc[j][i]);
            X1 = vec_ld (16, &lumSrc[j][i]);
            Y0 = vec_mradds (X0, YCoeffs[j], Y0);
            Y1 = vec_mradds (X1, YCoeffs[j], Y1);
        }

        U = RND;
        V = RND;
        /* extract 8 coeffs from U,V */
        for (j=0; j<chrFilterSize; j++) {
            X  = vec_ld (0, &chrUSrc[j][i/2]);
            U  = vec_mradds (X, CCoeffs[j], U);
            X  = vec_ld (0, &chrVSrc[j][i/2]);
            V  = vec_mradds (X, CCoeffs[j], V);
        }

        /* scale and clip signals */
        Y0 = vec_sra (Y0, SCL);
        Y1 = vec_sra (Y1, SCL);
        U  = vec_sra (U,  SCL);
        V  = vec_sra (V,  SCL);

        Y0 = vec_clip_s16 (Y0);
        Y1 = vec_clip_s16 (Y1);
        U  = vec_clip_s16 (U);
        V  = vec_clip_s16 (V);

        /* now we have
           Y0= y0 y1 y2 y3 y4 y5 y6 y7     Y1= y8 y9 y10 y11 y12 y13 y14 y15
           U = u0 u1 u2 u3 u4 u5 u6 u7     V = v0 v1 v2 v3 v4 v5 v6 v7

           Y0= y0 y1 y2 y3 y4 y5 y6 y7    Y1= y8 y9 y10 y11 y12 y13 y14 y15
           U0= u0 u0 u1 u1 u2 u2 u3 u3    U1= u4 u4 u5 u5 u6 u6 u7 u7
           V0= v0 v0 v1 v1 v2 v2 v3 v3    V1= v4 v4 v5 v5 v6 v6 v7 v7
        */

        U0 = vec_mergeh (U,U);
        V0 = vec_mergeh (V,V);

        U1 = vec_mergel (U,U);
        V1 = vec_mergel (V,V);

        cvtyuvtoRGB (c, Y0,U0,V0,&R0,&G0,&B0);
        cvtyuvtoRGB (c, Y1,U1,V1,&R1,&G1,&B1);

        R  = vec_packclp (R0,R1);
        G  = vec_packclp (G0,G1);
        B  = vec_packclp (B0,B1);

        nout = (vector unsigned char *)scratch;
        switch(c->dstFormat) {
        case PIX_FMT_ABGR:  out_abgr  (R,G,B,nout); break;
        case PIX_FMT_BGRA:  out_bgra  (R,G,B,nout); break;
        case PIX_FMT_RGBA:  out_rgba  (R,G,B,nout); break;
        case PIX_FMT_ARGB:  out_argb  (R,G,B,nout); break;
        case PIX_FMT_RGB24: out_rgb24 (R,G,B,nout); break;
        case PIX_FMT_BGR24: out_bgr24 (R,G,B,nout); break;
        default:
            /* Unreachable, I think. */
            av_log(c, AV_LOG_ERROR, "altivec_yuv2packedX doesn't support %s output\n",
                   av_get_pix_fmt_name(c->dstFormat));
            return;
        }

        memcpy (&((uint32_t*)dest)[i], scratch, (dstW-i)/4);
    }

}