1 /*****************************************************************************
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
5 * $Id: idct.c,v 1.14 2001/08/22 17:21:45 massiot Exp $
7 * Authors: Gaƫl Hendryckx <jimmy@via.ecp.fr>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
22 *****************************************************************************/
24 #define MODULE_NAME idct
25 #include "modules_inner.h"
27 /*****************************************************************************
29 *****************************************************************************/
40 #include "vdec_idct.h"
43 #include "modules_export.h"
45 /*****************************************************************************
46 * Local and extern prototypes.
47 *****************************************************************************/
48 static void idct_getfunctions( function_list_t * p_function_list );
49 static int idct_Probe ( probedata_t *p_data );
50 static void vdec_NormScan ( u8 ppi_scan[2][64] );
52 /*****************************************************************************
53 * Build configuration tree.
54 *****************************************************************************/
56 ADD_WINDOW( "Configuration for IDCT module" )
57 ADD_COMMENT( "Ha, ha -- nothing to configure yet" )
61 p_module->i_capabilities = MODULE_CAPABILITY_NULL
62 | MODULE_CAPABILITY_IDCT;
63 p_module->psz_longname = "IDCT module";
67 idct_getfunctions( &p_module->p_functions->idct );
70 MODULE_DEACTIVATE_START
71 MODULE_DEACTIVATE_STOP
73 /* Following functions are local */
75 /*****************************************************************************
76 * Functions exported as capabilities. They are declared as static so that
77 * we don't pollute the namespace too much.
78 *****************************************************************************/
79 static void idct_getfunctions( function_list_t * p_function_list )
81 p_function_list->pf_probe = idct_Probe;
82 #define F p_function_list->functions.idct
83 F.pf_idct_init = _M( vdec_InitIDCT );
84 F.pf_sparse_idct = _M( vdec_SparseIDCT );
85 F.pf_idct = _M( vdec_IDCT );
86 F.pf_norm_scan = vdec_NormScan;
87 F.pf_decode_init = _M( vdec_InitDecode );
88 F.pf_addblock = _M( vdec_AddBlock );
89 F.pf_copyblock = _M( vdec_CopyBlock );
93 /*****************************************************************************
94 * idct_Probe: returns a preference score
95 *****************************************************************************/
96 static int idct_Probe( probedata_t *p_data )
98 if( TestMethod( IDCT_METHOD_VAR, "idct" )
99 || TestMethod( IDCT_METHOD_VAR, "c" ))
104 /* This plugin always works */
108 /*****************************************************************************
109 * vdec_NormScan : Unused in this IDCT
110 *****************************************************************************/
111 static void vdec_NormScan( u8 ppi_scan[2][64] )
115 /*****************************************************************************
116 * vdec_IDCT : IDCT function for normal matrices
117 *****************************************************************************/
118 void _M( vdec_IDCT )( void * p_unused_data, dctelem_t * p_block,
121 s32 tmp0, tmp1, tmp2, tmp3;
122 s32 tmp10, tmp11, tmp12, tmp13;
123 s32 z1, z2, z3, z4, z5;
124 s32 d0, d1, d2, d3, d4, d5, d6, d7;
130 /* Pass 1: process rows. */
131 /* Note results are scaled up by sqrt(8) compared to a true IDCT; */
132 /* furthermore, we scale the results by 2**PASS1_BITS. */
136 for (rowctr = DCTSIZE-1; rowctr >= 0; rowctr--)
138 /* Due to quantization, we will usually find that many of the input
139 * coefficients are zero, especially the AC terms. We can exploit this
140 * by short-circuiting the IDCT calculation for any row in which all
141 * the AC terms are zero. In that case each output is equal to the
142 * DC coefficient (with scale factor as needed).
143 * With typical images and quantization tables, half or more of the
144 * row DCT calculations can be simplified this way.
147 register int * idataptr = (int*)dataptr;
150 if ( (d1 == 0) && ((idataptr[1] | idataptr[2] | idataptr[3]) == 0) )
152 /* AC terms all zero */
155 /* Compute a 32 bit value to assign. */
156 dctelem_t dcval = (dctelem_t) (d0 << PASS1_BITS);
157 register int v = (dcval & 0xffff) | (dcval << 16);
165 dataptr += DCTSIZE; /* advance pointer to next row */
175 /* Even part: reverse the even part of the forward DCT. */
176 /* The rotator is sqrt(2)*c(-6). */
185 /* d0 != 0, d2 != 0, d4 != 0, d6 != 0 */
186 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
187 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
188 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
190 tmp0 = (d0 + d4) << CONST_BITS;
191 tmp1 = (d0 - d4) << CONST_BITS;
200 /* d0 == 0, d2 != 0, d4 != 0, d6 != 0 */
201 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
202 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
203 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
205 tmp0 = d4 << CONST_BITS;
210 tmp12 = -(tmp0 + tmp2);
217 /* d0 != 0, d2 == 0, d4 != 0, d6 != 0 */
218 tmp2 = MULTIPLY(d6, - FIX2(1.306562965));
219 tmp3 = MULTIPLY(d6, FIX(0.541196100));
221 tmp0 = (d0 + d4) << CONST_BITS;
222 tmp1 = (d0 - d4) << CONST_BITS;
231 /* d0 == 0, d2 == 0, d4 != 0, d6 != 0 */
232 tmp2 = MULTIPLY(d6, - FIX2(1.306562965));
233 tmp3 = MULTIPLY(d6, FIX(0.541196100));
235 tmp0 = d4 << CONST_BITS;
240 tmp12 = -(tmp0 + tmp2);
250 /* d0 != 0, d2 != 0, d4 == 0, d6 != 0 */
251 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
252 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
253 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
255 tmp0 = d0 << CONST_BITS;
264 /* d0 == 0, d2 != 0, d4 == 0, d6 != 0 */
265 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
266 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
267 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
279 /* d0 != 0, d2 == 0, d4 == 0, d6 != 0 */
280 tmp2 = MULTIPLY(d6, - FIX2(1.306562965));
281 tmp3 = MULTIPLY(d6, FIX(0.541196100));
283 tmp0 = d0 << CONST_BITS;
292 /* d0 == 0, d2 == 0, d4 == 0, d6 != 0 */
293 tmp2 = MULTIPLY(d6, - FIX2(1.306562965));
294 tmp3 = MULTIPLY(d6, FIX(0.541196100));
312 /* d0 != 0, d2 != 0, d4 != 0, d6 == 0 */
313 tmp2 = MULTIPLY(d2, FIX(0.541196100));
314 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
316 tmp0 = (d0 + d4) << CONST_BITS;
317 tmp1 = (d0 - d4) << CONST_BITS;
326 /* d0 == 0, d2 != 0, d4 != 0, d6 == 0 */
327 tmp2 = MULTIPLY(d2, FIX(0.541196100));
328 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
330 tmp0 = d4 << CONST_BITS;
335 tmp12 = -(tmp0 + tmp2);
342 /* d0 != 0, d2 == 0, d4 != 0, d6 == 0 */
343 tmp10 = tmp13 = (d0 + d4) << CONST_BITS;
344 tmp11 = tmp12 = (d0 - d4) << CONST_BITS;
348 /* d0 == 0, d2 == 0, d4 != 0, d6 == 0 */
349 tmp10 = tmp13 = d4 << CONST_BITS;
350 tmp11 = tmp12 = -tmp10;
360 /* d0 != 0, d2 != 0, d4 == 0, d6 == 0 */
361 tmp2 = MULTIPLY(d2, FIX(0.541196100));
362 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
364 tmp0 = d0 << CONST_BITS;
373 /* d0 == 0, d2 != 0, d4 == 0, d6 == 0 */
374 tmp2 = MULTIPLY(d2, FIX(0.541196100));
375 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
387 /* d0 != 0, d2 == 0, d4 == 0, d6 == 0 */
388 tmp10 = tmp13 = tmp11 = tmp12 = d0 << CONST_BITS;
392 /* d0 == 0, d2 == 0, d4 == 0, d6 == 0 */
393 tmp10 = tmp13 = tmp11 = tmp12 = 0;
400 /* Odd part per figure 8; the matrix is unitary and hence its
401 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
412 /* d1 != 0, d3 != 0, d5 != 0, d7 != 0 */
417 z5 = MULTIPLY(z3 + z4, FIX(1.175875602));
419 tmp0 = MULTIPLY(d7, FIX(0.298631336));
420 tmp1 = MULTIPLY(d5, FIX(2.053119869));
421 tmp2 = MULTIPLY(d3, FIX(3.072711026));
422 tmp3 = MULTIPLY(d1, FIX(1.501321110));
423 z1 = MULTIPLY(z1, - FIX(0.899976223));
424 z2 = MULTIPLY(z2, - FIX(2.562915447));
425 z3 = MULTIPLY(z3, - FIX(1.961570560));
426 z4 = MULTIPLY(z4, - FIX(0.390180644));
438 /* d1 == 0, d3 != 0, d5 != 0, d7 != 0 */
441 z5 = MULTIPLY(z3 + d5, FIX(1.175875602));
443 tmp0 = MULTIPLY(d7, FIX(0.298631336));
444 tmp1 = MULTIPLY(d5, FIX(2.053119869));
445 tmp2 = MULTIPLY(d3, FIX(3.072711026));
446 z1 = MULTIPLY(d7, - FIX(0.899976223));
447 z2 = MULTIPLY(z2, - FIX(2.562915447));
448 z3 = MULTIPLY(z3, - FIX(1.961570560));
449 z4 = MULTIPLY(d5, - FIX(0.390180644));
464 /* d1 != 0, d3 == 0, d5 != 0, d7 != 0 */
467 z5 = MULTIPLY(d7 + z4, FIX(1.175875602));
469 tmp0 = MULTIPLY(d7, FIX(0.298631336));
470 tmp1 = MULTIPLY(d5, FIX(2.053119869));
471 tmp3 = MULTIPLY(d1, FIX(1.501321110));
472 z1 = MULTIPLY(z1, - FIX(0.899976223));
473 z2 = MULTIPLY(d5, - FIX(2.562915447));
474 z3 = MULTIPLY(d7, - FIX(1.961570560));
475 z4 = MULTIPLY(z4, - FIX(0.390180644));
487 /* d1 == 0, d3 == 0, d5 != 0, d7 != 0 */
488 z5 = MULTIPLY(d7 + d5, FIX(1.175875602));
490 tmp0 = MULTIPLY(d7, - FIX2(0.601344887));
491 tmp1 = MULTIPLY(d5, - FIX2(0.509795578));
492 z1 = MULTIPLY(d7, - FIX(0.899976223));
493 z3 = MULTIPLY(d7, - FIX(1.961570560));
494 z2 = MULTIPLY(d5, - FIX(2.562915447));
495 z4 = MULTIPLY(d5, - FIX(0.390180644));
513 /* d1 != 0, d3 != 0, d5 == 0, d7 != 0 */
516 z5 = MULTIPLY(z3 + d1, FIX(1.175875602));
518 tmp0 = MULTIPLY(d7, FIX(0.298631336));
519 tmp2 = MULTIPLY(d3, FIX(3.072711026));
520 tmp3 = MULTIPLY(d1, FIX(1.501321110));
521 z1 = MULTIPLY(z1, - FIX(0.899976223));
522 z2 = MULTIPLY(d3, - FIX(2.562915447));
523 z3 = MULTIPLY(z3, - FIX(1.961570560));
524 z4 = MULTIPLY(d1, - FIX(0.390180644));
536 /* d1 == 0, d3 != 0, d5 == 0, d7 != 0 */
538 z5 = MULTIPLY(z3, FIX(1.175875602));
540 tmp0 = MULTIPLY(d7, - FIX2(0.601344887));
541 tmp2 = MULTIPLY(d3, FIX(0.509795579));
542 z1 = MULTIPLY(d7, - FIX(0.899976223));
543 z2 = MULTIPLY(d3, - FIX(2.562915447));
544 z3 = MULTIPLY(z3, - FIX2(0.785694958));
556 /* d1 != 0, d3 == 0, d5 == 0, d7 != 0 */
558 z5 = MULTIPLY(z1, FIX(1.175875602));
560 tmp0 = MULTIPLY(d7, - FIX2(1.662939224));
561 tmp3 = MULTIPLY(d1, FIX2(1.111140466));
562 z1 = MULTIPLY(z1, FIX2(0.275899379));
563 z3 = MULTIPLY(d7, - FIX(1.961570560));
564 z4 = MULTIPLY(d1, - FIX(0.390180644));
573 /* d1 == 0, d3 == 0, d5 == 0, d7 != 0 */
574 tmp0 = MULTIPLY(d7, - FIX2(1.387039845));
575 tmp1 = MULTIPLY(d7, FIX(1.175875602));
576 tmp2 = MULTIPLY(d7, - FIX2(0.785694958));
577 tmp3 = MULTIPLY(d7, FIX2(0.275899379));
590 /* d1 != 0, d3 != 0, d5 != 0, d7 == 0 */
593 z5 = MULTIPLY(d3 + z4, FIX(1.175875602));
595 tmp1 = MULTIPLY(d5, FIX(2.053119869));
596 tmp2 = MULTIPLY(d3, FIX(3.072711026));
597 tmp3 = MULTIPLY(d1, FIX(1.501321110));
598 z1 = MULTIPLY(d1, - FIX(0.899976223));
599 z2 = MULTIPLY(z2, - FIX(2.562915447));
600 z3 = MULTIPLY(d3, - FIX(1.961570560));
601 z4 = MULTIPLY(z4, - FIX(0.390180644));
613 /* d1 == 0, d3 != 0, d5 != 0, d7 == 0 */
615 z5 = MULTIPLY(z2, FIX(1.175875602));
617 tmp1 = MULTIPLY(d5, FIX2(1.662939225));
618 tmp2 = MULTIPLY(d3, FIX2(1.111140466));
619 z2 = MULTIPLY(z2, - FIX2(1.387039845));
620 z3 = MULTIPLY(d3, - FIX(1.961570560));
621 z4 = MULTIPLY(d5, - FIX(0.390180644));
633 /* d1 != 0, d3 == 0, d5 != 0, d7 == 0 */
635 z5 = MULTIPLY(z4, FIX(1.175875602));
637 tmp1 = MULTIPLY(d5, - FIX2(0.509795578));
638 tmp3 = MULTIPLY(d1, FIX2(0.601344887));
639 z1 = MULTIPLY(d1, - FIX(0.899976223));
640 z2 = MULTIPLY(d5, - FIX(2.562915447));
641 z4 = MULTIPLY(z4, FIX2(0.785694958));
650 /* d1 == 0, d3 == 0, d5 != 0, d7 == 0 */
651 tmp0 = MULTIPLY(d5, FIX(1.175875602));
652 tmp1 = MULTIPLY(d5, FIX2(0.275899380));
653 tmp2 = MULTIPLY(d5, - FIX2(1.387039845));
654 tmp3 = MULTIPLY(d5, FIX2(0.785694958));
664 /* d1 != 0, d3 != 0, d5 == 0, d7 == 0 */
667 tmp2 = MULTIPLY(d3, - FIX(1.451774981));
668 tmp3 = MULTIPLY(d1, (FIX(0.211164243) - 1));
669 z1 = MULTIPLY(d1, FIX(1.061594337));
670 z2 = MULTIPLY(d3, - FIX(2.172734803));
671 z4 = MULTIPLY(z5, FIX(0.785694958));
672 z5 = MULTIPLY(z5, FIX(1.175875602));
681 /* d1 == 0, d3 != 0, d5 == 0, d7 == 0 */
682 tmp0 = MULTIPLY(d3, - FIX2(0.785694958));
683 tmp1 = MULTIPLY(d3, - FIX2(1.387039845));
684 tmp2 = MULTIPLY(d3, - FIX2(0.275899379));
685 tmp3 = MULTIPLY(d3, FIX(1.175875602));
692 /* d1 != 0, d3 == 0, d5 == 0, d7 == 0 */
693 tmp0 = MULTIPLY(d1, FIX2(0.275899379));
694 tmp1 = MULTIPLY(d1, FIX2(0.785694958));
695 tmp2 = MULTIPLY(d1, FIX(1.175875602));
696 tmp3 = MULTIPLY(d1, FIX2(1.387039845));
700 /* d1 == 0, d3 == 0, d5 == 0, d7 == 0 */
701 tmp0 = tmp1 = tmp2 = tmp3 = 0;
707 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
709 dataptr[0] = (dctelem_t) DESCALE(tmp10 + tmp3, CONST_BITS-PASS1_BITS);
710 dataptr[7] = (dctelem_t) DESCALE(tmp10 - tmp3, CONST_BITS-PASS1_BITS);
711 dataptr[1] = (dctelem_t) DESCALE(tmp11 + tmp2, CONST_BITS-PASS1_BITS);
712 dataptr[6] = (dctelem_t) DESCALE(tmp11 - tmp2, CONST_BITS-PASS1_BITS);
713 dataptr[2] = (dctelem_t) DESCALE(tmp12 + tmp1, CONST_BITS-PASS1_BITS);
714 dataptr[5] = (dctelem_t) DESCALE(tmp12 - tmp1, CONST_BITS-PASS1_BITS);
715 dataptr[3] = (dctelem_t) DESCALE(tmp13 + tmp0, CONST_BITS-PASS1_BITS);
716 dataptr[4] = (dctelem_t) DESCALE(tmp13 - tmp0, CONST_BITS-PASS1_BITS);
718 dataptr += DCTSIZE; /* advance pointer to next row */
721 /* Pass 2: process columns. */
722 /* Note that we must descale the results by a factor of 8 == 2**3, */
723 /* and also undo the PASS1_BITS scaling. */
726 for (rowctr = DCTSIZE-1; rowctr >= 0; rowctr--)
728 /* Columns of zeroes can be exploited in the same way as we did with rows.
729 * However, the row calculation has created many nonzero AC terms, so the
730 * simplification applies less often (typically 5% to 10% of the time).
731 * On machines with very fast multiplication, it's possible that the
732 * test takes more time than it's worth. In that case this section
733 * may be commented out.
736 d0 = dataptr[DCTSIZE*0];
737 d1 = dataptr[DCTSIZE*1];
738 d2 = dataptr[DCTSIZE*2];
739 d3 = dataptr[DCTSIZE*3];
740 d4 = dataptr[DCTSIZE*4];
741 d5 = dataptr[DCTSIZE*5];
742 d6 = dataptr[DCTSIZE*6];
743 d7 = dataptr[DCTSIZE*7];
745 /* Even part: reverse the even part of the forward DCT. */
746 /* The rotator is sqrt(2)*c(-6). */
755 /* d0 != 0, d2 != 0, d4 != 0, d6 != 0 */
756 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
757 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
758 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
760 tmp0 = (d0 + d4) << CONST_BITS;
761 tmp1 = (d0 - d4) << CONST_BITS;
770 /* d0 == 0, d2 != 0, d4 != 0, d6 != 0 */
771 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
772 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
773 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
775 tmp0 = d4 << CONST_BITS;
780 tmp12 = -(tmp0 + tmp2);
787 /* d0 != 0, d2 == 0, d4 != 0, d6 != 0 */
788 tmp2 = MULTIPLY(d6, - FIX2(1.306562965));
789 tmp3 = MULTIPLY(d6, FIX(0.541196100));
791 tmp0 = (d0 + d4) << CONST_BITS;
792 tmp1 = (d0 - d4) << CONST_BITS;
801 /* d0 == 0, d2 == 0, d4 != 0, d6 != 0 */
802 tmp2 = MULTIPLY(d6, -FIX2(1.306562965));
803 tmp3 = MULTIPLY(d6, FIX(0.541196100));
805 tmp0 = d4 << CONST_BITS;
810 tmp12 = -(tmp0 + tmp2);
820 /* d0 != 0, d2 != 0, d4 == 0, d6 != 0 */
821 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
822 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
823 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
825 tmp0 = d0 << CONST_BITS;
834 /* d0 == 0, d2 != 0, d4 == 0, d6 != 0 */
835 z1 = MULTIPLY(d2 + d6, FIX(0.541196100));
836 tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065));
837 tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865));
849 /* d0 != 0, d2 == 0, d4 == 0, d6 != 0 */
850 tmp2 = MULTIPLY(d6, - FIX2(1.306562965));
851 tmp3 = MULTIPLY(d6, FIX(0.541196100));
853 tmp0 = d0 << CONST_BITS;
862 /* d0 == 0, d2 == 0, d4 == 0, d6 != 0 */
863 tmp2 = MULTIPLY(d6, - FIX2(1.306562965));
864 tmp3 = MULTIPLY(d6, FIX(0.541196100));
881 /* d0 != 0, d2 != 0, d4 != 0, d6 == 0 */
882 tmp2 = MULTIPLY(d2, FIX(0.541196100));
883 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
885 tmp0 = (d0 + d4) << CONST_BITS;
886 tmp1 = (d0 - d4) << CONST_BITS;
895 /* d0 == 0, d2 != 0, d4 != 0, d6 == 0 */
896 tmp2 = MULTIPLY(d2, FIX(0.541196100));
897 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
899 tmp0 = d4 << CONST_BITS;
904 tmp12 = -(tmp0 + tmp2);
911 /* d0 != 0, d2 == 0, d4 != 0, d6 == 0 */
912 tmp10 = tmp13 = (d0 + d4) << CONST_BITS;
913 tmp11 = tmp12 = (d0 - d4) << CONST_BITS;
917 /* d0 == 0, d2 == 0, d4 != 0, d6 == 0 */
918 tmp10 = tmp13 = d4 << CONST_BITS;
919 tmp11 = tmp12 = -tmp10;
929 /* d0 != 0, d2 != 0, d4 == 0, d6 == 0 */
930 tmp2 = MULTIPLY(d2, FIX(0.541196100));
931 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
933 tmp0 = d0 << CONST_BITS;
942 /* d0 == 0, d2 != 0, d4 == 0, d6 == 0 */
943 tmp2 = MULTIPLY(d2, FIX(0.541196100));
944 tmp3 = MULTIPLY(d2, (FIX(1.306562965) + .5));
956 /* d0 != 0, d2 == 0, d4 == 0, d6 == 0 */
957 tmp10 = tmp13 = tmp11 = tmp12 = d0 << CONST_BITS;
961 /* d0 == 0, d2 == 0, d4 == 0, d6 == 0 */
962 tmp10 = tmp13 = tmp11 = tmp12 = 0;
968 /* Odd part per figure 8; the matrix is unitary and hence its
969 * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
979 /* d1 != 0, d3 != 0, d5 != 0, d7 != 0 */
984 z5 = MULTIPLY(z3 + z4, FIX(1.175875602));
986 tmp0 = MULTIPLY(d7, FIX(0.298631336));
987 tmp1 = MULTIPLY(d5, FIX(2.053119869));
988 tmp2 = MULTIPLY(d3, FIX(3.072711026));
989 tmp3 = MULTIPLY(d1, FIX(1.501321110));
990 z1 = MULTIPLY(z1, - FIX(0.899976223));
991 z2 = MULTIPLY(z2, - FIX(2.562915447));
992 z3 = MULTIPLY(z3, - FIX(1.961570560));
993 z4 = MULTIPLY(z4, - FIX(0.390180644));
1005 /* d1 == 0, d3 != 0, d5 != 0, d7 != 0 */
1008 z5 = MULTIPLY(z3 + d5, FIX(1.175875602));
1010 tmp0 = MULTIPLY(d7, FIX(0.298631336));
1011 tmp1 = MULTIPLY(d5, FIX(2.053119869));
1012 tmp2 = MULTIPLY(d3, FIX(3.072711026));
1013 z1 = MULTIPLY(d7, - FIX(0.899976223));
1014 z2 = MULTIPLY(z2, - FIX(2.562915447));
1015 z3 = MULTIPLY(z3, - FIX(1.961570560));
1016 z4 = MULTIPLY(d5, - FIX(0.390180644));
1031 /* d1 != 0, d3 == 0, d5 != 0, d7 != 0 */
1034 z5 = MULTIPLY(d7 + z4, FIX(1.175875602));
1036 tmp0 = MULTIPLY(d7, FIX(0.298631336));
1037 tmp1 = MULTIPLY(d5, FIX(2.053119869));
1038 tmp3 = MULTIPLY(d1, FIX(1.501321110));
1039 z1 = MULTIPLY(z1, - FIX(0.899976223));
1040 z2 = MULTIPLY(d5, - FIX(2.562915447));
1041 z3 = MULTIPLY(d7, - FIX(1.961570560));
1042 z4 = MULTIPLY(z4, - FIX(0.390180644));
1054 /* d1 == 0, d3 == 0, d5 != 0, d7 != 0 */
1055 z5 = MULTIPLY(d5 + d7, FIX(1.175875602));
1057 tmp0 = MULTIPLY(d7, - FIX2(0.601344887));
1058 tmp1 = MULTIPLY(d5, - FIX2(0.509795578));
1059 z1 = MULTIPLY(d7, - FIX(0.899976223));
1060 z3 = MULTIPLY(d7, - FIX(1.961570560));
1061 z2 = MULTIPLY(d5, - FIX(2.562915447));
1062 z4 = MULTIPLY(d5, - FIX(0.390180644));
1080 /* d1 != 0, d3 != 0, d5 == 0, d7 != 0 */
1083 z5 = MULTIPLY(z3 + d1, FIX(1.175875602));
1085 tmp0 = MULTIPLY(d7, FIX(0.298631336));
1086 tmp2 = MULTIPLY(d3, FIX(3.072711026));
1087 tmp3 = MULTIPLY(d1, FIX(1.501321110));
1088 z1 = MULTIPLY(z1, - FIX(0.899976223));
1089 z2 = MULTIPLY(d3, - FIX(2.562915447));
1090 z3 = MULTIPLY(z3, - FIX(1.961570560));
1091 z4 = MULTIPLY(d1, - FIX(0.390180644));
1103 /* d1 == 0, d3 != 0, d5 == 0, d7 != 0 */
1105 z5 = MULTIPLY(z3, FIX(1.175875602));
1107 tmp0 = MULTIPLY(d7, - FIX2(0.601344887));
1108 z1 = MULTIPLY(d7, - FIX(0.899976223));
1109 tmp2 = MULTIPLY(d3, FIX(0.509795579));
1110 z2 = MULTIPLY(d3, - FIX(2.562915447));
1111 z3 = MULTIPLY(z3, - FIX2(0.785694958));
1123 /* d1 != 0, d3 == 0, d5 == 0, d7 != 0 */
1125 z5 = MULTIPLY(z1, FIX(1.175875602));
1127 tmp0 = MULTIPLY(d7, - FIX2(1.662939224));
1128 tmp3 = MULTIPLY(d1, FIX2(1.111140466));
1129 z1 = MULTIPLY(z1, FIX2(0.275899379));
1130 z3 = MULTIPLY(d7, - FIX(1.961570560));
1131 z4 = MULTIPLY(d1, - FIX(0.390180644));
1140 /* d1 == 0, d3 == 0, d5 == 0, d7 != 0 */
1141 tmp0 = MULTIPLY(d7, - FIX2(1.387039845));
1142 tmp1 = MULTIPLY(d7, FIX(1.175875602));
1143 tmp2 = MULTIPLY(d7, - FIX2(0.785694958));
1144 tmp3 = MULTIPLY(d7, FIX2(0.275899379));
1157 /* d1 != 0, d3 != 0, d5 != 0, d7 == 0 */
1160 z5 = MULTIPLY(d3 + z4, FIX(1.175875602));
1162 tmp1 = MULTIPLY(d5, FIX(2.053119869));
1163 tmp2 = MULTIPLY(d3, FIX(3.072711026));
1164 tmp3 = MULTIPLY(d1, FIX(1.501321110));
1165 z1 = MULTIPLY(d1, - FIX(0.899976223));
1166 z2 = MULTIPLY(z2, - FIX(2.562915447));
1167 z3 = MULTIPLY(d3, - FIX(1.961570560));
1168 z4 = MULTIPLY(z4, - FIX(0.390180644));
1180 /* d1 == 0, d3 != 0, d5 != 0, d7 == 0 */
1182 z5 = MULTIPLY(z2, FIX(1.175875602));
1184 tmp1 = MULTIPLY(d5, FIX2(1.662939225));
1185 tmp2 = MULTIPLY(d3, FIX2(1.111140466));
1186 z2 = MULTIPLY(z2, - FIX2(1.387039845));
1187 z3 = MULTIPLY(d3, - FIX(1.961570560));
1188 z4 = MULTIPLY(d5, - FIX(0.390180644));
1200 /* d1 != 0, d3 == 0, d5 != 0, d7 == 0 */
1202 z5 = MULTIPLY(z4, FIX(1.175875602));
1204 tmp1 = MULTIPLY(d5, - FIX2(0.509795578));
1205 tmp3 = MULTIPLY(d1, FIX2(0.601344887));
1206 z1 = MULTIPLY(d1, - FIX(0.899976223));
1207 z2 = MULTIPLY(d5, - FIX(2.562915447));
1208 z4 = MULTIPLY(z4, FIX2(0.785694958));
1217 /* d1 == 0, d3 == 0, d5 != 0, d7 == 0 */
1218 tmp0 = MULTIPLY(d5, FIX(1.175875602));
1219 tmp1 = MULTIPLY(d5, FIX2(0.275899380));
1220 tmp2 = MULTIPLY(d5, - FIX2(1.387039845));
1221 tmp3 = MULTIPLY(d5, FIX2(0.785694958));
1231 /* d1 != 0, d3 != 0, d5 == 0, d7 == 0 */
1234 tmp2 = MULTIPLY(d3, - FIX(1.451774981));
1235 tmp3 = MULTIPLY(d1, (FIX(0.211164243) - 1));
1236 z1 = MULTIPLY(d1, FIX(1.061594337));
1237 z2 = MULTIPLY(d3, - FIX(2.172734803));
1238 z4 = MULTIPLY(z5, FIX(0.785694958));
1239 z5 = MULTIPLY(z5, FIX(1.175875602));
1248 /* d1 == 0, d3 != 0, d5 == 0, d7 == 0 */
1249 tmp0 = MULTIPLY(d3, - FIX2(0.785694958));
1250 tmp1 = MULTIPLY(d3, - FIX2(1.387039845));
1251 tmp2 = MULTIPLY(d3, - FIX2(0.275899379));
1252 tmp3 = MULTIPLY(d3, FIX(1.175875602));
1259 /* d1 != 0, d3 == 0, d5 == 0, d7 == 0 */
1260 tmp0 = MULTIPLY(d1, FIX2(0.275899379));
1261 tmp1 = MULTIPLY(d1, FIX2(0.785694958));
1262 tmp2 = MULTIPLY(d1, FIX(1.175875602));
1263 tmp3 = MULTIPLY(d1, FIX2(1.387039845));
1267 /* d1 == 0, d3 == 0, d5 == 0, d7 == 0 */
1268 tmp0 = tmp1 = tmp2 = tmp3 = 0;
1274 /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
1276 dataptr[DCTSIZE*0] = (dctelem_t) DESCALE(tmp10 + tmp3,
1277 CONST_BITS+PASS1_BITS+3);
1278 dataptr[DCTSIZE*7] = (dctelem_t) DESCALE(tmp10 - tmp3,
1279 CONST_BITS+PASS1_BITS+3);
1280 dataptr[DCTSIZE*1] = (dctelem_t) DESCALE(tmp11 + tmp2,
1281 CONST_BITS+PASS1_BITS+3);
1282 dataptr[DCTSIZE*6] = (dctelem_t) DESCALE(tmp11 - tmp2,
1283 CONST_BITS+PASS1_BITS+3);
1284 dataptr[DCTSIZE*2] = (dctelem_t) DESCALE(tmp12 + tmp1,
1285 CONST_BITS+PASS1_BITS+3);
1286 dataptr[DCTSIZE*5] = (dctelem_t) DESCALE(tmp12 - tmp1,
1287 CONST_BITS+PASS1_BITS+3);
1288 dataptr[DCTSIZE*3] = (dctelem_t) DESCALE(tmp13 + tmp0,
1289 CONST_BITS+PASS1_BITS+3);
1290 dataptr[DCTSIZE*4] = (dctelem_t) DESCALE(tmp13 - tmp0,
1291 CONST_BITS+PASS1_BITS+3);
1293 dataptr++; /* advance pointer to next column */