Libav
simple_idct_template.c
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1 /*
2  * Simple IDCT
3  *
4  * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
28 /*
29  based upon some outcommented c code from mpeg2dec (idct_mmx.c
30  written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>)
31  */
32 
33 #include "simple_idct.h"
34 
35 #include "bit_depth_template.c"
36 
37 #undef W1
38 #undef W2
39 #undef W3
40 #undef W4
41 #undef W5
42 #undef W6
43 #undef W7
44 #undef ROW_SHIFT
45 #undef COL_SHIFT
46 #undef DC_SHIFT
47 #undef MUL
48 #undef MAC
49 
50 #if BIT_DEPTH == 8
51 
52 #define W1 22725 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
53 #define W2 21407 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
54 #define W3 19266 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
55 #define W4 16383 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
56 #define W5 12873 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
57 #define W6 8867 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
58 #define W7 4520 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
59 
60 #define ROW_SHIFT 11
61 #define COL_SHIFT 20
62 #define DC_SHIFT 3
63 
64 #define MUL(a, b) MUL16(a, b)
65 #define MAC(a, b, c) MAC16(a, b, c)
66 
67 #elif BIT_DEPTH == 10
68 
69 #define W1 90901
70 #define W2 85627
71 #define W3 77062
72 #define W4 65535
73 #define W5 51491
74 #define W6 35468
75 #define W7 18081
76 
77 #define ROW_SHIFT 15
78 #define COL_SHIFT 20
79 #define DC_SHIFT 1
80 
81 #define MUL(a, b) ((a) * (b))
82 #define MAC(a, b, c) ((a) += (b) * (c))
83 
84 #else
85 
86 #error "Unsupported bitdepth"
87 
88 #endif
89 
90 static inline void FUNC(idctRowCondDC)(int16_t *row, int extra_shift)
91 {
92  int a0, a1, a2, a3, b0, b1, b2, b3;
93 
94 #if HAVE_FAST_64BIT
95 #define ROW0_MASK (0xffffLL << 48 * HAVE_BIGENDIAN)
96  if (((((uint64_t *)row)[0] & ~ROW0_MASK) | ((uint64_t *)row)[1]) == 0) {
97  uint64_t temp;
98  if (DC_SHIFT - extra_shift > 0) {
99  temp = (row[0] << (DC_SHIFT - extra_shift)) & 0xffff;
100  } else {
101  temp = (row[0] >> (extra_shift - DC_SHIFT)) & 0xffff;
102  }
103  temp += temp << 16;
104  temp += temp << 32;
105  ((uint64_t *)row)[0] = temp;
106  ((uint64_t *)row)[1] = temp;
107  return;
108  }
109 #else
110  if (!(((uint32_t*)row)[1] |
111  ((uint32_t*)row)[2] |
112  ((uint32_t*)row)[3] |
113  row[1])) {
114  uint32_t temp;
115  if (DC_SHIFT - extra_shift > 0) {
116  temp = (row[0] << (DC_SHIFT - extra_shift)) & 0xffff;
117  } else {
118  temp = (row[0] >> (extra_shift - DC_SHIFT)) & 0xffff;
119  }
120  temp += temp << 16;
121  ((uint32_t*)row)[0]=((uint32_t*)row)[1] =
122  ((uint32_t*)row)[2]=((uint32_t*)row)[3] = temp;
123  return;
124  }
125 #endif
126 
127  a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1));
128  a1 = a0;
129  a2 = a0;
130  a3 = a0;
131 
132  a0 += W2 * row[2];
133  a1 += W6 * row[2];
134  a2 -= W6 * row[2];
135  a3 -= W2 * row[2];
136 
137  b0 = MUL(W1, row[1]);
138  MAC(b0, W3, row[3]);
139  b1 = MUL(W3, row[1]);
140  MAC(b1, -W7, row[3]);
141  b2 = MUL(W5, row[1]);
142  MAC(b2, -W1, row[3]);
143  b3 = MUL(W7, row[1]);
144  MAC(b3, -W5, row[3]);
145 
146  if (AV_RN64A(row + 4)) {
147  a0 += W4*row[4] + W6*row[6];
148  a1 += - W4*row[4] - W2*row[6];
149  a2 += - W4*row[4] + W2*row[6];
150  a3 += W4*row[4] - W6*row[6];
151 
152  MAC(b0, W5, row[5]);
153  MAC(b0, W7, row[7]);
154 
155  MAC(b1, -W1, row[5]);
156  MAC(b1, -W5, row[7]);
157 
158  MAC(b2, W7, row[5]);
159  MAC(b2, W3, row[7]);
160 
161  MAC(b3, W3, row[5]);
162  MAC(b3, -W1, row[7]);
163  }
164 
165  row[0] = (a0 + b0) >> (ROW_SHIFT + extra_shift);
166  row[7] = (a0 - b0) >> (ROW_SHIFT + extra_shift);
167  row[1] = (a1 + b1) >> (ROW_SHIFT + extra_shift);
168  row[6] = (a1 - b1) >> (ROW_SHIFT + extra_shift);
169  row[2] = (a2 + b2) >> (ROW_SHIFT + extra_shift);
170  row[5] = (a2 - b2) >> (ROW_SHIFT + extra_shift);
171  row[3] = (a3 + b3) >> (ROW_SHIFT + extra_shift);
172  row[4] = (a3 - b3) >> (ROW_SHIFT + extra_shift);
173 }
174 
175 #define IDCT_COLS do { \
176  a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4)); \
177  a1 = a0; \
178  a2 = a0; \
179  a3 = a0; \
180  \
181  a0 += W2*col[8*2]; \
182  a1 += W6*col[8*2]; \
183  a2 += -W6*col[8*2]; \
184  a3 += -W2*col[8*2]; \
185  \
186  b0 = MUL(W1, col[8*1]); \
187  b1 = MUL(W3, col[8*1]); \
188  b2 = MUL(W5, col[8*1]); \
189  b3 = MUL(W7, col[8*1]); \
190  \
191  MAC(b0, W3, col[8*3]); \
192  MAC(b1, -W7, col[8*3]); \
193  MAC(b2, -W1, col[8*3]); \
194  MAC(b3, -W5, col[8*3]); \
195  \
196  if (col[8*4]) { \
197  a0 += W4*col[8*4]; \
198  a1 += -W4*col[8*4]; \
199  a2 += -W4*col[8*4]; \
200  a3 += W4*col[8*4]; \
201  } \
202  \
203  if (col[8*5]) { \
204  MAC(b0, W5, col[8*5]); \
205  MAC(b1, -W1, col[8*5]); \
206  MAC(b2, W7, col[8*5]); \
207  MAC(b3, W3, col[8*5]); \
208  } \
209  \
210  if (col[8*6]) { \
211  a0 += W6*col[8*6]; \
212  a1 += -W2*col[8*6]; \
213  a2 += W2*col[8*6]; \
214  a3 += -W6*col[8*6]; \
215  } \
216  \
217  if (col[8*7]) { \
218  MAC(b0, W7, col[8*7]); \
219  MAC(b1, -W5, col[8*7]); \
220  MAC(b2, W3, col[8*7]); \
221  MAC(b3, -W1, col[8*7]); \
222  } \
223  } while (0)
224 
225 static inline void FUNC(idctSparseColPut)(pixel *dest, int line_size,
226  int16_t *col)
227 {
228  int a0, a1, a2, a3, b0, b1, b2, b3;
229 
230  IDCT_COLS;
231 
232  dest[0] = av_clip_pixel((a0 + b0) >> COL_SHIFT);
233  dest += line_size;
234  dest[0] = av_clip_pixel((a1 + b1) >> COL_SHIFT);
235  dest += line_size;
236  dest[0] = av_clip_pixel((a2 + b2) >> COL_SHIFT);
237  dest += line_size;
238  dest[0] = av_clip_pixel((a3 + b3) >> COL_SHIFT);
239  dest += line_size;
240  dest[0] = av_clip_pixel((a3 - b3) >> COL_SHIFT);
241  dest += line_size;
242  dest[0] = av_clip_pixel((a2 - b2) >> COL_SHIFT);
243  dest += line_size;
244  dest[0] = av_clip_pixel((a1 - b1) >> COL_SHIFT);
245  dest += line_size;
246  dest[0] = av_clip_pixel((a0 - b0) >> COL_SHIFT);
247 }
248 
249 static inline void FUNC(idctSparseColAdd)(pixel *dest, int line_size,
250  int16_t *col)
251 {
252  int a0, a1, a2, a3, b0, b1, b2, b3;
253 
254  IDCT_COLS;
255 
256  dest[0] = av_clip_pixel(dest[0] + ((a0 + b0) >> COL_SHIFT));
257  dest += line_size;
258  dest[0] = av_clip_pixel(dest[0] + ((a1 + b1) >> COL_SHIFT));
259  dest += line_size;
260  dest[0] = av_clip_pixel(dest[0] + ((a2 + b2) >> COL_SHIFT));
261  dest += line_size;
262  dest[0] = av_clip_pixel(dest[0] + ((a3 + b3) >> COL_SHIFT));
263  dest += line_size;
264  dest[0] = av_clip_pixel(dest[0] + ((a3 - b3) >> COL_SHIFT));
265  dest += line_size;
266  dest[0] = av_clip_pixel(dest[0] + ((a2 - b2) >> COL_SHIFT));
267  dest += line_size;
268  dest[0] = av_clip_pixel(dest[0] + ((a1 - b1) >> COL_SHIFT));
269  dest += line_size;
270  dest[0] = av_clip_pixel(dest[0] + ((a0 - b0) >> COL_SHIFT));
271 }
272 
273 static inline void FUNC(idctSparseCol)(int16_t *col)
274 {
275  int a0, a1, a2, a3, b0, b1, b2, b3;
276 
277  IDCT_COLS;
278 
279  col[0 ] = ((a0 + b0) >> COL_SHIFT);
280  col[8 ] = ((a1 + b1) >> COL_SHIFT);
281  col[16] = ((a2 + b2) >> COL_SHIFT);
282  col[24] = ((a3 + b3) >> COL_SHIFT);
283  col[32] = ((a3 - b3) >> COL_SHIFT);
284  col[40] = ((a2 - b2) >> COL_SHIFT);
285  col[48] = ((a1 - b1) >> COL_SHIFT);
286  col[56] = ((a0 - b0) >> COL_SHIFT);
287 }
288 
289 void FUNC(ff_simple_idct_put)(uint8_t *dest_, int line_size, int16_t *block)
290 {
291  pixel *dest = (pixel *)dest_;
292  int i;
293 
294  line_size /= sizeof(pixel);
295 
296  for (i = 0; i < 8; i++)
297  FUNC(idctRowCondDC)(block + i*8, 0);
298 
299  for (i = 0; i < 8; i++)
300  FUNC(idctSparseColPut)(dest + i, line_size, block + i);
301 }
302 
303 void FUNC(ff_simple_idct_add)(uint8_t *dest_, int line_size, int16_t *block)
304 {
305  pixel *dest = (pixel *)dest_;
306  int i;
307 
308  line_size /= sizeof(pixel);
309 
310  for (i = 0; i < 8; i++)
311  FUNC(idctRowCondDC)(block + i*8, 0);
312 
313  for (i = 0; i < 8; i++)
314  FUNC(idctSparseColAdd)(dest + i, line_size, block + i);
315 }
316 
317 void FUNC(ff_simple_idct)(int16_t *block)
318 {
319  int i;
320 
321  for (i = 0; i < 8; i++)
322  FUNC(idctRowCondDC)(block + i*8, 0);
323 
324  for (i = 0; i < 8; i++)
325  FUNC(idctSparseCol)(block + i);
326 }
#define W4
Definition: wmv2dsp.c:30
#define W6
Definition: wmv2dsp.c:32
#define av_clip_pixel(a)
uint8_t
#define W5
Definition: wmv2dsp.c:31
#define FUNC(a)
#define W1
Definition: wmv2dsp.c:27
#define W7
Definition: wmv2dsp.c:33
#define pixel
void FUNC() ff_simple_idct(int16_t *block)
static void FUNC() idctSparseColPut(pixel *dest, int line_size, int16_t *col)
static void FUNC() idctRowCondDC(int16_t *row, int extra_shift)
static void FUNC() idctSparseColAdd(pixel *dest, int line_size, int16_t *col)
#define MUL(a, b)
#define IDCT_COLS
static void FUNC() idctSparseCol(int16_t *col)
void FUNC() ff_simple_idct_put(uint8_t *dest_, int line_size, int16_t *block)
simple idct header.
#define W3
Definition: wmv2dsp.c:29
void FUNC() ff_simple_idct_add(uint8_t *dest_, int line_size, int16_t *block)
#define W2
Definition: wmv2dsp.c:28
#define AV_RN64A(p)
Definition: intreadwrite.h:450
static int16_t block[64]
Definition: dct-test.c:88