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1
/*
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 * Simple IDCT
3
 *
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 * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at>
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14
 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 */
20
 
21
/**
22
 * @file simple_idct.c
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 * simpleidct in C.
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 */
25
 
26
/*
27
  based upon some outcommented c code from mpeg2dec (idct_mmx.c
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  written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>) 
29
 */
30
#include "avcodec.h"
31
#include "dsputil.h"
32
#include "simple_idct.h"
33

    
34
#if 0
35
#define W1 2841 /* 2048*sqrt (2)*cos (1*pi/16) */
36
#define W2 2676 /* 2048*sqrt (2)*cos (2*pi/16) */
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#define W3 2408 /* 2048*sqrt (2)*cos (3*pi/16) */
38
#define W4 2048 /* 2048*sqrt (2)*cos (4*pi/16) */
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#define W5 1609 /* 2048*sqrt (2)*cos (5*pi/16) */
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#define W6 1108 /* 2048*sqrt (2)*cos (6*pi/16) */
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#define W7 565  /* 2048*sqrt (2)*cos (7*pi/16) */
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#define ROW_SHIFT 8
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#define COL_SHIFT 17
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#else
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#define W1  22725  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
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#define W2  21407  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
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#define W3  19266  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
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#define W4  16383  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
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#define W5  12873  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
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#define W6  8867   //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
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#define W7  4520   //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
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#define ROW_SHIFT 11
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#define COL_SHIFT 20 // 6
54
#endif
55

    
56
#if defined(ARCH_POWERPC_405)
57

    
58
/* signed 16x16 -> 32 multiply add accumulate */
59
#define MAC16(rt, ra, rb) \
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    asm ("maclhw %0, %2, %3" : "=r" (rt) : "0" (rt), "r" (ra), "r" (rb));
61

    
62
/* signed 16x16 -> 32 multiply */
63
#define MUL16(rt, ra, rb) \
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    asm ("mullhw %0, %1, %2" : "=r" (rt) : "r" (ra), "r" (rb));
65

    
66
#else
67

    
68
/* signed 16x16 -> 32 multiply add accumulate */
69
#define MAC16(rt, ra, rb) rt += (ra) * (rb)
70

    
71
/* signed 16x16 -> 32 multiply */
72
#define MUL16(rt, ra, rb) rt = (ra) * (rb)
73

    
74
#endif
75

    
76
static inline void idctRowCondDC (DCTELEM * row)
77
{
78
        int a0, a1, a2, a3, b0, b1, b2, b3;
79
#ifdef FAST_64BIT
80
        uint64_t temp;
81
#else
82
        uint32_t temp;
83
#endif
84

    
85
#ifdef FAST_64BIT
86
#ifdef WORDS_BIGENDIAN
87
#define ROW0_MASK 0xffff000000000000LL
88
#else
89
#define ROW0_MASK 0xffffLL
90
#endif
91
        if(sizeof(DCTELEM)==2){
92
            if ( ((((uint64_t *)row)[0] & ~ROW0_MASK) | 
93
                  ((uint64_t *)row)[1]) == 0) {
94
                temp = (row[0] << 3) & 0xffff;
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                temp += temp << 16;
96
                temp += temp << 32;
97
                ((uint64_t *)row)[0] = temp;
98
                ((uint64_t *)row)[1] = temp;
99
                return;
100
            }
101
        }else{
102
            if (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) {
103
                row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3;
104
                return;
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            }
106
        }
107
#else
108
        if(sizeof(DCTELEM)==2){
109
            if (!(((uint32_t*)row)[1] |
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                  ((uint32_t*)row)[2] |
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                  ((uint32_t*)row)[3] | 
112
                  row[1])) {
113
                temp = (row[0] << 3) & 0xffff;
114
                temp += temp << 16;
115
                ((uint32_t*)row)[0]=((uint32_t*)row)[1] =
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                ((uint32_t*)row)[2]=((uint32_t*)row)[3] = temp;
117
                return;
118
            }
119
        }else{
120
            if (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) {
121
                row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3;
122
                return;
123
            }
124
        }
125
#endif
126

    
127
        a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1));
128
        a1 = a0;
129
        a2 = a0;
130
        a3 = a0;
131

    
132
        /* no need to optimize : gcc does it */
133
        a0 += W2 * row[2];
134
        a1 += W6 * row[2];
135
        a2 -= W6 * row[2];
136
        a3 -= W2 * row[2];
137

    
138
        MUL16(b0, W1, row[1]);
139
        MAC16(b0, W3, row[3]);
140
        MUL16(b1, W3, row[1]);
141
        MAC16(b1, -W7, row[3]);
142
        MUL16(b2, W5, row[1]);
143
        MAC16(b2, -W1, row[3]);
144
        MUL16(b3, W7, row[1]);
145
        MAC16(b3, -W5, row[3]);
146

    
147
#ifdef FAST_64BIT
148
        temp = ((uint64_t*)row)[1];
149
#else
150
        temp = ((uint32_t*)row)[2] | ((uint32_t*)row)[3];
151
#endif
152
        if (temp != 0) {
153
            a0 += W4*row[4] + W6*row[6];
154
            a1 += - W4*row[4] - W2*row[6];
155
            a2 += - W4*row[4] + W2*row[6];
156
            a3 += W4*row[4] - W6*row[6];
157

    
158
            MAC16(b0, W5, row[5]);
159
            MAC16(b0, W7, row[7]);
160
            
161
            MAC16(b1, -W1, row[5]);
162
            MAC16(b1, -W5, row[7]);
163
            
164
            MAC16(b2, W7, row[5]);
165
            MAC16(b2, W3, row[7]);
166
            
167
            MAC16(b3, W3, row[5]);
168
            MAC16(b3, -W1, row[7]);
169
        }
170

    
171
        row[0] = (a0 + b0) >> ROW_SHIFT;
172
        row[7] = (a0 - b0) >> ROW_SHIFT;
173
        row[1] = (a1 + b1) >> ROW_SHIFT;
174
        row[6] = (a1 - b1) >> ROW_SHIFT;
175
        row[2] = (a2 + b2) >> ROW_SHIFT;
176
        row[5] = (a2 - b2) >> ROW_SHIFT;
177
        row[3] = (a3 + b3) >> ROW_SHIFT;
178
        row[4] = (a3 - b3) >> ROW_SHIFT;
179
}
180

    
181
static inline void idctSparseColPut (uint8_t *dest, int line_size, 
182
                                     DCTELEM * col)
183
{
184
        int a0, a1, a2, a3, b0, b1, b2, b3;
185
        uint8_t *cm = cropTbl + MAX_NEG_CROP;
186

    
187
        /* XXX: I did that only to give same values as previous code */
188
        a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4));
189
        a1 = a0;
190
        a2 = a0;
191
        a3 = a0;
192

    
193
        a0 +=  + W2*col[8*2];
194
        a1 +=  + W6*col[8*2];
195
        a2 +=  - W6*col[8*2];
196
        a3 +=  - W2*col[8*2];
197

    
198
        MUL16(b0, W1, col[8*1]);
199
        MUL16(b1, W3, col[8*1]);
200
        MUL16(b2, W5, col[8*1]);
201
        MUL16(b3, W7, col[8*1]);
202

    
203
        MAC16(b0, + W3, col[8*3]);
204
        MAC16(b1, - W7, col[8*3]);
205
        MAC16(b2, - W1, col[8*3]);
206
        MAC16(b3, - W5, col[8*3]);
207

    
208
        if(col[8*4]){
209
            a0 += + W4*col[8*4];
210
            a1 += - W4*col[8*4];
211
            a2 += - W4*col[8*4];
212
            a3 += + W4*col[8*4];
213
        }
214

    
215
        if (col[8*5]) {
216
            MAC16(b0, + W5, col[8*5]);
217
            MAC16(b1, - W1, col[8*5]);
218
            MAC16(b2, + W7, col[8*5]);
219
            MAC16(b3, + W3, col[8*5]);
220
        }
221

    
222
        if(col[8*6]){
223
            a0 += + W6*col[8*6];
224
            a1 += - W2*col[8*6];
225
            a2 += + W2*col[8*6];
226
            a3 += - W6*col[8*6];
227
        }
228

    
229
        if (col[8*7]) {
230
            MAC16(b0, + W7, col[8*7]);
231
            MAC16(b1, - W5, col[8*7]);
232
            MAC16(b2, + W3, col[8*7]);
233
            MAC16(b3, - W1, col[8*7]);
234
        }
235

    
236
        dest[0] = cm[(a0 + b0) >> COL_SHIFT];
237
        dest += line_size;
238
        dest[0] = cm[(a1 + b1) >> COL_SHIFT];
239
        dest += line_size;
240
        dest[0] = cm[(a2 + b2) >> COL_SHIFT];
241
        dest += line_size;
242
        dest[0] = cm[(a3 + b3) >> COL_SHIFT];
243
        dest += line_size;
244
        dest[0] = cm[(a3 - b3) >> COL_SHIFT];
245
        dest += line_size;
246
        dest[0] = cm[(a2 - b2) >> COL_SHIFT];
247
        dest += line_size;
248
        dest[0] = cm[(a1 - b1) >> COL_SHIFT];
249
        dest += line_size;
250
        dest[0] = cm[(a0 - b0) >> COL_SHIFT];
251
}
252

    
253
static inline void idctSparseColAdd (uint8_t *dest, int line_size, 
254
                                     DCTELEM * col)
255
{
256
        int a0, a1, a2, a3, b0, b1, b2, b3;
257
        uint8_t *cm = cropTbl + MAX_NEG_CROP;
258

    
259
        /* XXX: I did that only to give same values as previous code */
260
        a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4));
261
        a1 = a0;
262
        a2 = a0;
263
        a3 = a0;
264

    
265
        a0 +=  + W2*col[8*2];
266
        a1 +=  + W6*col[8*2];
267
        a2 +=  - W6*col[8*2];
268
        a3 +=  - W2*col[8*2];
269

    
270
        MUL16(b0, W1, col[8*1]);
271
        MUL16(b1, W3, col[8*1]);
272
        MUL16(b2, W5, col[8*1]);
273
        MUL16(b3, W7, col[8*1]);
274

    
275
        MAC16(b0, + W3, col[8*3]);
276
        MAC16(b1, - W7, col[8*3]);
277
        MAC16(b2, - W1, col[8*3]);
278
        MAC16(b3, - W5, col[8*3]);
279

    
280
        if(col[8*4]){
281
            a0 += + W4*col[8*4];
282
            a1 += - W4*col[8*4];
283
            a2 += - W4*col[8*4];
284
            a3 += + W4*col[8*4];
285
        }
286

    
287
        if (col[8*5]) {
288
            MAC16(b0, + W5, col[8*5]);
289
            MAC16(b1, - W1, col[8*5]);
290
            MAC16(b2, + W7, col[8*5]);
291
            MAC16(b3, + W3, col[8*5]);
292
        }
293

    
294
        if(col[8*6]){
295
            a0 += + W6*col[8*6];
296
            a1 += - W2*col[8*6];
297
            a2 += + W2*col[8*6];
298
            a3 += - W6*col[8*6];
299
        }
300

    
301
        if (col[8*7]) {
302
            MAC16(b0, + W7, col[8*7]);
303
            MAC16(b1, - W5, col[8*7]);
304
            MAC16(b2, + W3, col[8*7]);
305
            MAC16(b3, - W1, col[8*7]);
306
        }
307

    
308
        dest[0] = cm[dest[0] + ((a0 + b0) >> COL_SHIFT)];
309
        dest += line_size;
310
        dest[0] = cm[dest[0] + ((a1 + b1) >> COL_SHIFT)];
311
        dest += line_size;
312
        dest[0] = cm[dest[0] + ((a2 + b2) >> COL_SHIFT)];
313
        dest += line_size;
314
        dest[0] = cm[dest[0] + ((a3 + b3) >> COL_SHIFT)];
315
        dest += line_size;
316
        dest[0] = cm[dest[0] + ((a3 - b3) >> COL_SHIFT)];
317
        dest += line_size;
318
        dest[0] = cm[dest[0] + ((a2 - b2) >> COL_SHIFT)];
319
        dest += line_size;
320
        dest[0] = cm[dest[0] + ((a1 - b1) >> COL_SHIFT)];
321
        dest += line_size;
322
        dest[0] = cm[dest[0] + ((a0 - b0) >> COL_SHIFT)];
323
}
324

    
325
static inline void idctSparseCol (DCTELEM * col)
326
{
327
        int a0, a1, a2, a3, b0, b1, b2, b3;
328

    
329
        /* XXX: I did that only to give same values as previous code */
330
        a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4));
331
        a1 = a0;
332
        a2 = a0;
333
        a3 = a0;
334

    
335
        a0 +=  + W2*col[8*2];
336
        a1 +=  + W6*col[8*2];
337
        a2 +=  - W6*col[8*2];
338
        a3 +=  - W2*col[8*2];
339

    
340
        MUL16(b0, W1, col[8*1]);
341
        MUL16(b1, W3, col[8*1]);
342
        MUL16(b2, W5, col[8*1]);
343
        MUL16(b3, W7, col[8*1]);
344

    
345
        MAC16(b0, + W3, col[8*3]);
346
        MAC16(b1, - W7, col[8*3]);
347
        MAC16(b2, - W1, col[8*3]);
348
        MAC16(b3, - W5, col[8*3]);
349

    
350
        if(col[8*4]){
351
            a0 += + W4*col[8*4];
352
            a1 += - W4*col[8*4];
353
            a2 += - W4*col[8*4];
354
            a3 += + W4*col[8*4];
355
        }
356

    
357
        if (col[8*5]) {
358
            MAC16(b0, + W5, col[8*5]);
359
            MAC16(b1, - W1, col[8*5]);
360
            MAC16(b2, + W7, col[8*5]);
361
            MAC16(b3, + W3, col[8*5]);
362
        }
363

    
364
        if(col[8*6]){
365
            a0 += + W6*col[8*6];
366
            a1 += - W2*col[8*6];
367
            a2 += + W2*col[8*6];
368
            a3 += - W6*col[8*6];
369
        }
370

    
371
        if (col[8*7]) {
372
            MAC16(b0, + W7, col[8*7]);
373
            MAC16(b1, - W5, col[8*7]);
374
            MAC16(b2, + W3, col[8*7]);
375
            MAC16(b3, - W1, col[8*7]);
376
        }
377

    
378
        col[0 ] = ((a0 + b0) >> COL_SHIFT);
379
        col[8 ] = ((a1 + b1) >> COL_SHIFT);
380
        col[16] = ((a2 + b2) >> COL_SHIFT);
381
        col[24] = ((a3 + b3) >> COL_SHIFT);
382
        col[32] = ((a3 - b3) >> COL_SHIFT);
383
        col[40] = ((a2 - b2) >> COL_SHIFT);
384
        col[48] = ((a1 - b1) >> COL_SHIFT);
385
        col[56] = ((a0 - b0) >> COL_SHIFT);
386
}
387

    
388
void simple_idct_put(uint8_t *dest, int line_size, DCTELEM *block)
389
{
390
    int i;
391
    for(i=0; i<8; i++)
392
        idctRowCondDC(block + i*8);
393
    
394
    for(i=0; i<8; i++)
395
        idctSparseColPut(dest + i, line_size, block + i);
396
}
397

    
398
void simple_idct_add(uint8_t *dest, int line_size, DCTELEM *block)
399
{
400
    int i;
401
    for(i=0; i<8; i++)
402
        idctRowCondDC(block + i*8);
403
    
404
    for(i=0; i<8; i++)
405
        idctSparseColAdd(dest + i, line_size, block + i);
406
}
407

    
408
void simple_idct(DCTELEM *block)
409
{
410
    int i;
411
    for(i=0; i<8; i++)
412
        idctRowCondDC(block + i*8);
413
    
414
    for(i=0; i<8; i++)
415
        idctSparseCol(block + i);
416
}
417

    
418
/* 2x4x8 idct */
419

    
420
#define CN_SHIFT 12
421
#define C_FIX(x) ((int)((x) * (1 << CN_SHIFT) + 0.5))
422
#define C1 C_FIX(0.6532814824)
423
#define C2 C_FIX(0.2705980501)
424

    
425
/* row idct is multiple by 16 * sqrt(2.0), col idct4 is normalized,
426
   and the butterfly must be multiplied by 0.5 * sqrt(2.0) */
427
#define C_SHIFT (4+1+12)
428

    
429
static inline void idct4col(uint8_t *dest, int line_size, const DCTELEM *col)
430
{
431
    int c0, c1, c2, c3, a0, a1, a2, a3;
432
    const uint8_t *cm = cropTbl + MAX_NEG_CROP;
433

    
434
    a0 = col[8*0];
435
    a1 = col[8*2];
436
    a2 = col[8*4];
437
    a3 = col[8*6];
438
    c0 = ((a0 + a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
439
    c2 = ((a0 - a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
440
    c1 = a1 * C1 + a3 * C2;
441
    c3 = a1 * C2 - a3 * C1;
442
    dest[0] = cm[(c0 + c1) >> C_SHIFT];
443
    dest += line_size;
444
    dest[0] = cm[(c2 + c3) >> C_SHIFT];
445
    dest += line_size;
446
    dest[0] = cm[(c2 - c3) >> C_SHIFT];
447
    dest += line_size;
448
    dest[0] = cm[(c0 - c1) >> C_SHIFT];
449
}
450

    
451
#define BF(k) \
452
{\
453
    int a0, a1;\
454
    a0 = ptr[k];\
455
    a1 = ptr[8 + k];\
456
    ptr[k] = a0 + a1;\
457
    ptr[8 + k] = a0 - a1;\
458
}
459

    
460
/* only used by DV codec. The input must be interlaced. 128 is added
461
   to the pixels before clamping to avoid systematic error
462
   (1024*sqrt(2)) offset would be needed otherwise. */
463
/* XXX: I think a 1.0/sqrt(2) normalization should be needed to
464
   compensate the extra butterfly stage - I don't have the full DV
465
   specification */
466
void simple_idct248_put(uint8_t *dest, int line_size, DCTELEM *block)
467
{
468
    int i;
469
    DCTELEM *ptr;
470
    
471
    /* butterfly */
472
    ptr = block;
473
    for(i=0;i<4;i++) {
474
        BF(0);
475
        BF(1);
476
        BF(2);
477
        BF(3);
478
        BF(4);
479
        BF(5);
480
        BF(6);
481
        BF(7);
482
        ptr += 2 * 8;
483
    }
484

    
485
    /* IDCT8 on each line */
486
    for(i=0; i<8; i++) {
487
        idctRowCondDC(block + i*8);
488
    }
489

    
490
    /* IDCT4 and store */
491
    for(i=0;i<8;i++) {
492
        idct4col(dest + i, 2 * line_size, block + i);
493
        idct4col(dest + line_size + i, 2 * line_size, block + 8 + i);
494
    }
495
}
496

    
497
/* 8x4 & 4x8 WMV2 IDCT */
498
#undef CN_SHIFT
499
#undef C_SHIFT
500
#undef C_FIX
501
#undef C1
502
#undef C2
503
#define CN_SHIFT 12
504
#define C_FIX(x) ((int)((x) * 1.414213562 * (1 << CN_SHIFT) + 0.5))
505
#define C1 C_FIX(0.6532814824)
506
#define C2 C_FIX(0.2705980501)
507
#define C3 C_FIX(0.5)
508
#define C_SHIFT (4+1+12)
509
static inline void idct4col_add(uint8_t *dest, int line_size, const DCTELEM *col)
510
{
511
    int c0, c1, c2, c3, a0, a1, a2, a3;
512
    const uint8_t *cm = cropTbl + MAX_NEG_CROP;
513

    
514
    a0 = col[8*0];
515
    a1 = col[8*1];
516
    a2 = col[8*2];
517
    a3 = col[8*3];
518
    c0 = (a0 + a2)*C3 + (1 << (C_SHIFT - 1));
519
    c2 = (a0 - a2)*C3 + (1 << (C_SHIFT - 1));
520
    c1 = a1 * C1 + a3 * C2;
521
    c3 = a1 * C2 - a3 * C1;
522
    dest[0] = cm[dest[0] + ((c0 + c1) >> C_SHIFT)];
523
    dest += line_size;
524
    dest[0] = cm[dest[0] + ((c2 + c3) >> C_SHIFT)];
525
    dest += line_size;
526
    dest[0] = cm[dest[0] + ((c2 - c3) >> C_SHIFT)];
527
    dest += line_size;
528
    dest[0] = cm[dest[0] + ((c0 - c1) >> C_SHIFT)];
529
}
530

    
531
#define RN_SHIFT 15
532
#define R_FIX(x) ((int)((x) * 1.414213562 * (1 << RN_SHIFT) + 0.5))
533
#define R1 R_FIX(0.6532814824)
534
#define R2 R_FIX(0.2705980501)
535
#define R3 R_FIX(0.5)
536
#define R_SHIFT 11
537
static inline void idct4row(DCTELEM *row)
538
{
539
    int c0, c1, c2, c3, a0, a1, a2, a3;
540
    //const uint8_t *cm = cropTbl + MAX_NEG_CROP;
541

    
542
    a0 = row[0];
543
    a1 = row[1];
544
    a2 = row[2];
545
    a3 = row[3];
546
    c0 = (a0 + a2)*R3 + (1 << (R_SHIFT - 1));
547
    c2 = (a0 - a2)*R3 + (1 << (R_SHIFT - 1));
548
    c1 = a1 * R1 + a3 * R2;
549
    c3 = a1 * R2 - a3 * R1;
550
    row[0]= (c0 + c1) >> R_SHIFT;
551
    row[1]= (c2 + c3) >> R_SHIFT;
552
    row[2]= (c2 - c3) >> R_SHIFT;
553
    row[3]= (c0 - c1) >> R_SHIFT;
554
}
555

    
556
void simple_idct84_add(uint8_t *dest, int line_size, DCTELEM *block)
557
{
558
    int i;
559

    
560
    /* IDCT8 on each line */
561
    for(i=0; i<4; i++) {
562
        idctRowCondDC(block + i*8);
563
    }
564

    
565
    /* IDCT4 and store */
566
    for(i=0;i<8;i++) {
567
        idct4col_add(dest + i, line_size, block + i);
568
    }
569
}
570

    
571
void simple_idct48_add(uint8_t *dest, int line_size, DCTELEM *block)
572
{
573
    int i;
574

    
575
    /* IDCT4 on each line */
576
    for(i=0; i<8; i++) {
577
        idct4row(block + i*8);
578
    }
579

    
580
    /* IDCT8 and store */
581
    for(i=0; i<4; i++){
582
        idctSparseColAdd(dest + i, line_size, block + i);
583
    }
584
}
585