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/*
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 * Simple IDCT
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 *
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 * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at>
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 *
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 * This file is part of Libav.
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 *
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 * Libav 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 2.1 of the License, or (at your option) any later version.
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 *
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 * Libav 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
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 * 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 Libav; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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23
/**
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 * @file
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 * simpleidct in C.
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 */
27

    
28
/*
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  based upon some outcommented c code from mpeg2dec (idct_mmx.c
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  written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>)
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 */
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#include "avcodec.h"
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#include "dsputil.h"
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#include "mathops.h"
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#include "simple_idct.h"
36

    
37
#if 0
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#define W1 2841 /* 2048*sqrt (2)*cos (1*pi/16) */
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#define W2 2676 /* 2048*sqrt (2)*cos (2*pi/16) */
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#define W3 2408 /* 2048*sqrt (2)*cos (3*pi/16) */
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#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
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#endif
58

    
59
static inline void idctRowCondDC (DCTELEM * row)
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{
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        int a0, a1, a2, a3, b0, b1, b2, b3;
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#if HAVE_FAST_64BIT
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        uint64_t temp;
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#else
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        uint32_t temp;
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#endif
67

    
68
#if HAVE_FAST_64BIT
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#if HAVE_BIGENDIAN
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#define ROW0_MASK 0xffff000000000000LL
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#else
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#define ROW0_MASK 0xffffLL
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#endif
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        if(sizeof(DCTELEM)==2){
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            if ( ((((uint64_t *)row)[0] & ~ROW0_MASK) |
76
                  ((uint64_t *)row)[1]) == 0) {
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                temp = (row[0] << 3) & 0xffff;
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                temp += temp << 16;
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                temp += temp << 32;
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                ((uint64_t *)row)[0] = temp;
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                ((uint64_t *)row)[1] = temp;
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                return;
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            }
84
        }else{
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            if (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) {
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                row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3;
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                return;
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            }
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        }
90
#else
91
        if(sizeof(DCTELEM)==2){
92
            if (!(((uint32_t*)row)[1] |
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                  ((uint32_t*)row)[2] |
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                  ((uint32_t*)row)[3] |
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                  row[1])) {
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                temp = (row[0] << 3) & 0xffff;
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                temp += temp << 16;
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                ((uint32_t*)row)[0]=((uint32_t*)row)[1] =
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                ((uint32_t*)row)[2]=((uint32_t*)row)[3] = temp;
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                return;
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            }
102
        }else{
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            if (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) {
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                row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3;
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                return;
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            }
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        }
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#endif
109

    
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        a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1));
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        a1 = a0;
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        a2 = a0;
113
        a3 = a0;
114

    
115
        /* no need to optimize : gcc does it */
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        a0 += W2 * row[2];
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        a1 += W6 * row[2];
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        a2 -= W6 * row[2];
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        a3 -= W2 * row[2];
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        b0 = MUL16(W1, row[1]);
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        MAC16(b0, W3, row[3]);
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        b1 = MUL16(W3, row[1]);
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        MAC16(b1, -W7, row[3]);
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        b2 = MUL16(W5, row[1]);
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        MAC16(b2, -W1, row[3]);
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        b3 = MUL16(W7, row[1]);
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        MAC16(b3, -W5, row[3]);
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130
#if HAVE_FAST_64BIT
131
        temp = ((uint64_t*)row)[1];
132
#else
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        temp = ((uint32_t*)row)[2] | ((uint32_t*)row)[3];
134
#endif
135
        if (temp != 0) {
136
            a0 += W4*row[4] + W6*row[6];
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            a1 += - W4*row[4] - W2*row[6];
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            a2 += - W4*row[4] + W2*row[6];
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            a3 += W4*row[4] - W6*row[6];
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141
            MAC16(b0, W5, row[5]);
142
            MAC16(b0, W7, row[7]);
143

    
144
            MAC16(b1, -W1, row[5]);
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            MAC16(b1, -W5, row[7]);
146

    
147
            MAC16(b2, W7, row[5]);
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            MAC16(b2, W3, row[7]);
149

    
150
            MAC16(b3, W3, row[5]);
151
            MAC16(b3, -W1, row[7]);
152
        }
153

    
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        row[0] = (a0 + b0) >> ROW_SHIFT;
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        row[7] = (a0 - b0) >> ROW_SHIFT;
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        row[1] = (a1 + b1) >> ROW_SHIFT;
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        row[6] = (a1 - b1) >> ROW_SHIFT;
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        row[2] = (a2 + b2) >> ROW_SHIFT;
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        row[5] = (a2 - b2) >> ROW_SHIFT;
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        row[3] = (a3 + b3) >> ROW_SHIFT;
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        row[4] = (a3 - b3) >> ROW_SHIFT;
162
}
163

    
164
static inline void idctSparseColPut (uint8_t *dest, int line_size,
165
                                     DCTELEM * col)
166
{
167
        int a0, a1, a2, a3, b0, b1, b2, b3;
168
        uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
169

    
170
        /* XXX: I did that only to give same values as previous code */
171
        a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4));
172
        a1 = a0;
173
        a2 = a0;
174
        a3 = a0;
175

    
176
        a0 +=  + W2*col[8*2];
177
        a1 +=  + W6*col[8*2];
178
        a2 +=  - W6*col[8*2];
179
        a3 +=  - W2*col[8*2];
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        b0 = MUL16(W1, col[8*1]);
182
        b1 = MUL16(W3, col[8*1]);
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        b2 = MUL16(W5, col[8*1]);
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        b3 = MUL16(W7, col[8*1]);
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186
        MAC16(b0, + W3, col[8*3]);
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        MAC16(b1, - W7, col[8*3]);
188
        MAC16(b2, - W1, col[8*3]);
189
        MAC16(b3, - W5, col[8*3]);
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191
        if(col[8*4]){
192
            a0 += + W4*col[8*4];
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            a1 += - W4*col[8*4];
194
            a2 += - W4*col[8*4];
195
            a3 += + W4*col[8*4];
196
        }
197

    
198
        if (col[8*5]) {
199
            MAC16(b0, + W5, col[8*5]);
200
            MAC16(b1, - W1, col[8*5]);
201
            MAC16(b2, + W7, col[8*5]);
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            MAC16(b3, + W3, col[8*5]);
203
        }
204

    
205
        if(col[8*6]){
206
            a0 += + W6*col[8*6];
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            a1 += - W2*col[8*6];
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            a2 += + W2*col[8*6];
209
            a3 += - W6*col[8*6];
210
        }
211

    
212
        if (col[8*7]) {
213
            MAC16(b0, + W7, col[8*7]);
214
            MAC16(b1, - W5, col[8*7]);
215
            MAC16(b2, + W3, col[8*7]);
216
            MAC16(b3, - W1, col[8*7]);
217
        }
218

    
219
        dest[0] = cm[(a0 + b0) >> COL_SHIFT];
220
        dest += line_size;
221
        dest[0] = cm[(a1 + b1) >> COL_SHIFT];
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        dest += line_size;
223
        dest[0] = cm[(a2 + b2) >> COL_SHIFT];
224
        dest += line_size;
225
        dest[0] = cm[(a3 + b3) >> COL_SHIFT];
226
        dest += line_size;
227
        dest[0] = cm[(a3 - b3) >> COL_SHIFT];
228
        dest += line_size;
229
        dest[0] = cm[(a2 - b2) >> COL_SHIFT];
230
        dest += line_size;
231
        dest[0] = cm[(a1 - b1) >> COL_SHIFT];
232
        dest += line_size;
233
        dest[0] = cm[(a0 - b0) >> COL_SHIFT];
234
}
235

    
236
static inline void idctSparseColAdd (uint8_t *dest, int line_size,
237
                                     DCTELEM * col)
238
{
239
        int a0, a1, a2, a3, b0, b1, b2, b3;
240
        uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
241

    
242
        /* XXX: I did that only to give same values as previous code */
243
        a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4));
244
        a1 = a0;
245
        a2 = a0;
246
        a3 = a0;
247

    
248
        a0 +=  + W2*col[8*2];
249
        a1 +=  + W6*col[8*2];
250
        a2 +=  - W6*col[8*2];
251
        a3 +=  - W2*col[8*2];
252

    
253
        b0 = MUL16(W1, col[8*1]);
254
        b1 = MUL16(W3, col[8*1]);
255
        b2 = MUL16(W5, col[8*1]);
256
        b3 = MUL16(W7, col[8*1]);
257

    
258
        MAC16(b0, + W3, col[8*3]);
259
        MAC16(b1, - W7, col[8*3]);
260
        MAC16(b2, - W1, col[8*3]);
261
        MAC16(b3, - W5, col[8*3]);
262

    
263
        if(col[8*4]){
264
            a0 += + W4*col[8*4];
265
            a1 += - W4*col[8*4];
266
            a2 += - W4*col[8*4];
267
            a3 += + W4*col[8*4];
268
        }
269

    
270
        if (col[8*5]) {
271
            MAC16(b0, + W5, col[8*5]);
272
            MAC16(b1, - W1, col[8*5]);
273
            MAC16(b2, + W7, col[8*5]);
274
            MAC16(b3, + W3, col[8*5]);
275
        }
276

    
277
        if(col[8*6]){
278
            a0 += + W6*col[8*6];
279
            a1 += - W2*col[8*6];
280
            a2 += + W2*col[8*6];
281
            a3 += - W6*col[8*6];
282
        }
283

    
284
        if (col[8*7]) {
285
            MAC16(b0, + W7, col[8*7]);
286
            MAC16(b1, - W5, col[8*7]);
287
            MAC16(b2, + W3, col[8*7]);
288
            MAC16(b3, - W1, col[8*7]);
289
        }
290

    
291
        dest[0] = cm[dest[0] + ((a0 + b0) >> COL_SHIFT)];
292
        dest += line_size;
293
        dest[0] = cm[dest[0] + ((a1 + b1) >> COL_SHIFT)];
294
        dest += line_size;
295
        dest[0] = cm[dest[0] + ((a2 + b2) >> COL_SHIFT)];
296
        dest += line_size;
297
        dest[0] = cm[dest[0] + ((a3 + b3) >> COL_SHIFT)];
298
        dest += line_size;
299
        dest[0] = cm[dest[0] + ((a3 - b3) >> COL_SHIFT)];
300
        dest += line_size;
301
        dest[0] = cm[dest[0] + ((a2 - b2) >> COL_SHIFT)];
302
        dest += line_size;
303
        dest[0] = cm[dest[0] + ((a1 - b1) >> COL_SHIFT)];
304
        dest += line_size;
305
        dest[0] = cm[dest[0] + ((a0 - b0) >> COL_SHIFT)];
306
}
307

    
308
static inline void idctSparseCol (DCTELEM * col)
309
{
310
        int a0, a1, a2, a3, b0, b1, b2, b3;
311

    
312
        /* XXX: I did that only to give same values as previous code */
313
        a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4));
314
        a1 = a0;
315
        a2 = a0;
316
        a3 = a0;
317

    
318
        a0 +=  + W2*col[8*2];
319
        a1 +=  + W6*col[8*2];
320
        a2 +=  - W6*col[8*2];
321
        a3 +=  - W2*col[8*2];
322

    
323
        b0 = MUL16(W1, col[8*1]);
324
        b1 = MUL16(W3, col[8*1]);
325
        b2 = MUL16(W5, col[8*1]);
326
        b3 = MUL16(W7, col[8*1]);
327

    
328
        MAC16(b0, + W3, col[8*3]);
329
        MAC16(b1, - W7, col[8*3]);
330
        MAC16(b2, - W1, col[8*3]);
331
        MAC16(b3, - W5, col[8*3]);
332

    
333
        if(col[8*4]){
334
            a0 += + W4*col[8*4];
335
            a1 += - W4*col[8*4];
336
            a2 += - W4*col[8*4];
337
            a3 += + W4*col[8*4];
338
        }
339

    
340
        if (col[8*5]) {
341
            MAC16(b0, + W5, col[8*5]);
342
            MAC16(b1, - W1, col[8*5]);
343
            MAC16(b2, + W7, col[8*5]);
344
            MAC16(b3, + W3, col[8*5]);
345
        }
346

    
347
        if(col[8*6]){
348
            a0 += + W6*col[8*6];
349
            a1 += - W2*col[8*6];
350
            a2 += + W2*col[8*6];
351
            a3 += - W6*col[8*6];
352
        }
353

    
354
        if (col[8*7]) {
355
            MAC16(b0, + W7, col[8*7]);
356
            MAC16(b1, - W5, col[8*7]);
357
            MAC16(b2, + W3, col[8*7]);
358
            MAC16(b3, - W1, col[8*7]);
359
        }
360

    
361
        col[0 ] = ((a0 + b0) >> COL_SHIFT);
362
        col[8 ] = ((a1 + b1) >> COL_SHIFT);
363
        col[16] = ((a2 + b2) >> COL_SHIFT);
364
        col[24] = ((a3 + b3) >> COL_SHIFT);
365
        col[32] = ((a3 - b3) >> COL_SHIFT);
366
        col[40] = ((a2 - b2) >> COL_SHIFT);
367
        col[48] = ((a1 - b1) >> COL_SHIFT);
368
        col[56] = ((a0 - b0) >> COL_SHIFT);
369
}
370

    
371
void ff_simple_idct_put(uint8_t *dest, int line_size, DCTELEM *block)
372
{
373
    int i;
374
    for(i=0; i<8; i++)
375
        idctRowCondDC(block + i*8);
376

    
377
    for(i=0; i<8; i++)
378
        idctSparseColPut(dest + i, line_size, block + i);
379
}
380

    
381
void ff_simple_idct_add(uint8_t *dest, int line_size, DCTELEM *block)
382
{
383
    int i;
384
    for(i=0; i<8; i++)
385
        idctRowCondDC(block + i*8);
386

    
387
    for(i=0; i<8; i++)
388
        idctSparseColAdd(dest + i, line_size, block + i);
389
}
390

    
391
void ff_simple_idct(DCTELEM *block)
392
{
393
    int i;
394
    for(i=0; i<8; i++)
395
        idctRowCondDC(block + i*8);
396

    
397
    for(i=0; i<8; i++)
398
        idctSparseCol(block + i);
399
}
400

    
401
/* 2x4x8 idct */
402

    
403
#define CN_SHIFT 12
404
#define C_FIX(x) ((int)((x) * (1 << CN_SHIFT) + 0.5))
405
#define C1 C_FIX(0.6532814824)
406
#define C2 C_FIX(0.2705980501)
407

    
408
/* row idct is multiple by 16 * sqrt(2.0), col idct4 is normalized,
409
   and the butterfly must be multiplied by 0.5 * sqrt(2.0) */
410
#define C_SHIFT (4+1+12)
411

    
412
static inline void idct4col_put(uint8_t *dest, int line_size, const DCTELEM *col)
413
{
414
    int c0, c1, c2, c3, a0, a1, a2, a3;
415
    const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
416

    
417
    a0 = col[8*0];
418
    a1 = col[8*2];
419
    a2 = col[8*4];
420
    a3 = col[8*6];
421
    c0 = ((a0 + a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
422
    c2 = ((a0 - a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
423
    c1 = a1 * C1 + a3 * C2;
424
    c3 = a1 * C2 - a3 * C1;
425
    dest[0] = cm[(c0 + c1) >> C_SHIFT];
426
    dest += line_size;
427
    dest[0] = cm[(c2 + c3) >> C_SHIFT];
428
    dest += line_size;
429
    dest[0] = cm[(c2 - c3) >> C_SHIFT];
430
    dest += line_size;
431
    dest[0] = cm[(c0 - c1) >> C_SHIFT];
432
}
433

    
434
#define BF(k) \
435
{\
436
    int a0, a1;\
437
    a0 = ptr[k];\
438
    a1 = ptr[8 + k];\
439
    ptr[k] = a0 + a1;\
440
    ptr[8 + k] = a0 - a1;\
441
}
442

    
443
/* only used by DV codec. The input must be interlaced. 128 is added
444
   to the pixels before clamping to avoid systematic error
445
   (1024*sqrt(2)) offset would be needed otherwise. */
446
/* XXX: I think a 1.0/sqrt(2) normalization should be needed to
447
   compensate the extra butterfly stage - I don't have the full DV
448
   specification */
449
void ff_simple_idct248_put(uint8_t *dest, int line_size, DCTELEM *block)
450
{
451
    int i;
452
    DCTELEM *ptr;
453

    
454
    /* butterfly */
455
    ptr = block;
456
    for(i=0;i<4;i++) {
457
        BF(0);
458
        BF(1);
459
        BF(2);
460
        BF(3);
461
        BF(4);
462
        BF(5);
463
        BF(6);
464
        BF(7);
465
        ptr += 2 * 8;
466
    }
467

    
468
    /* IDCT8 on each line */
469
    for(i=0; i<8; i++) {
470
        idctRowCondDC(block + i*8);
471
    }
472

    
473
    /* IDCT4 and store */
474
    for(i=0;i<8;i++) {
475
        idct4col_put(dest + i, 2 * line_size, block + i);
476
        idct4col_put(dest + line_size + i, 2 * line_size, block + 8 + i);
477
    }
478
}
479

    
480
/* 8x4 & 4x8 WMV2 IDCT */
481
#undef CN_SHIFT
482
#undef C_SHIFT
483
#undef C_FIX
484
#undef C1
485
#undef C2
486
#define CN_SHIFT 12
487
#define C_FIX(x) ((int)((x) * 1.414213562 * (1 << CN_SHIFT) + 0.5))
488
#define C1 C_FIX(0.6532814824)
489
#define C2 C_FIX(0.2705980501)
490
#define C3 C_FIX(0.5)
491
#define C_SHIFT (4+1+12)
492
static inline void idct4col_add(uint8_t *dest, int line_size, const DCTELEM *col)
493
{
494
    int c0, c1, c2, c3, a0, a1, a2, a3;
495
    const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
496

    
497
    a0 = col[8*0];
498
    a1 = col[8*1];
499
    a2 = col[8*2];
500
    a3 = col[8*3];
501
    c0 = (a0 + a2)*C3 + (1 << (C_SHIFT - 1));
502
    c2 = (a0 - a2)*C3 + (1 << (C_SHIFT - 1));
503
    c1 = a1 * C1 + a3 * C2;
504
    c3 = a1 * C2 - a3 * C1;
505
    dest[0] = cm[dest[0] + ((c0 + c1) >> C_SHIFT)];
506
    dest += line_size;
507
    dest[0] = cm[dest[0] + ((c2 + c3) >> C_SHIFT)];
508
    dest += line_size;
509
    dest[0] = cm[dest[0] + ((c2 - c3) >> C_SHIFT)];
510
    dest += line_size;
511
    dest[0] = cm[dest[0] + ((c0 - c1) >> C_SHIFT)];
512
}
513

    
514
#define RN_SHIFT 15
515
#define R_FIX(x) ((int)((x) * 1.414213562 * (1 << RN_SHIFT) + 0.5))
516
#define R1 R_FIX(0.6532814824)
517
#define R2 R_FIX(0.2705980501)
518
#define R3 R_FIX(0.5)
519
#define R_SHIFT 11
520
static inline void idct4row(DCTELEM *row)
521
{
522
    int c0, c1, c2, c3, a0, a1, a2, a3;
523
    //const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
524

    
525
    a0 = row[0];
526
    a1 = row[1];
527
    a2 = row[2];
528
    a3 = row[3];
529
    c0 = (a0 + a2)*R3 + (1 << (R_SHIFT - 1));
530
    c2 = (a0 - a2)*R3 + (1 << (R_SHIFT - 1));
531
    c1 = a1 * R1 + a3 * R2;
532
    c3 = a1 * R2 - a3 * R1;
533
    row[0]= (c0 + c1) >> R_SHIFT;
534
    row[1]= (c2 + c3) >> R_SHIFT;
535
    row[2]= (c2 - c3) >> R_SHIFT;
536
    row[3]= (c0 - c1) >> R_SHIFT;
537
}
538

    
539
void ff_simple_idct84_add(uint8_t *dest, int line_size, DCTELEM *block)
540
{
541
    int i;
542

    
543
    /* IDCT8 on each line */
544
    for(i=0; i<4; i++) {
545
        idctRowCondDC(block + i*8);
546
    }
547

    
548
    /* IDCT4 and store */
549
    for(i=0;i<8;i++) {
550
        idct4col_add(dest + i, line_size, block + i);
551
    }
552
}
553

    
554
void ff_simple_idct48_add(uint8_t *dest, int line_size, DCTELEM *block)
555
{
556
    int i;
557

    
558
    /* IDCT4 on each line */
559
    for(i=0; i<8; i++) {
560
        idct4row(block + i*8);
561
    }
562

    
563
    /* IDCT8 and store */
564
    for(i=0; i<4; i++){
565
        idctSparseColAdd(dest + i, line_size, block + i);
566
    }
567
}
568

    
569
void ff_simple_idct44_add(uint8_t *dest, int line_size, DCTELEM *block)
570
{
571
    int i;
572

    
573
    /* IDCT4 on each line */
574
    for(i=0; i<4; i++) {
575
        idct4row(block + i*8);
576
    }
577

    
578
    /* IDCT4 and store */
579
    for(i=0; i<4; i++){
580
        idct4col_add(dest + i, line_size, block + i);
581
    }
582
}