FFmpeg  4.0
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 FFmpeg.
7  *
8  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * simpleidct in C.
26  */
27 
28 /* Based upon some commented-out C code from mpeg2dec (idct_mmx.c
29  * written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>). */
30 
31 #include "simple_idct.h"
32 
33 #include "bit_depth_template.c"
34 
35 #undef W1
36 #undef W2
37 #undef W3
38 #undef W4
39 #undef W5
40 #undef W6
41 #undef W7
42 #undef ROW_SHIFT
43 #undef COL_SHIFT
44 #undef DC_SHIFT
45 #undef MUL
46 #undef MAC
47 
48 #if BIT_DEPTH == 8
49 
50 #define W1 22725 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
51 #define W2 21407 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
52 #define W3 19266 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
53 #define W4 16383 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
54 #define W5 12873 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
55 #define W6 8867 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
56 #define W7 4520 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
57 
58 #define ROW_SHIFT 11
59 #define COL_SHIFT 20
60 #define DC_SHIFT 3
61 
62 #define MUL(a, b) MUL16(a, b)
63 #define MAC(a, b, c) MAC16(a, b, c)
64 
65 #elif BIT_DEPTH == 10 || BIT_DEPTH == 12
66 
67 # if BIT_DEPTH == 10
68 #define W1 22725 // 90901
69 #define W2 21407 // 85627
70 #define W3 19265 // 77062
71 #define W4 16384 // 65535
72 #define W5 12873 // 51491
73 #define W6 8867 // 35468
74 #define W7 4520 // 18081
75 
76 # ifdef EXTRA_SHIFT
77 #define ROW_SHIFT 13
78 #define COL_SHIFT 18
79 #define DC_SHIFT 1
80 # elif IN_IDCT_DEPTH == 32
81 #define ROW_SHIFT 13
82 #define COL_SHIFT 21
83 #define DC_SHIFT 2
84 # else
85 #define ROW_SHIFT 12
86 #define COL_SHIFT 19
87 #define DC_SHIFT 2
88 # endif
89 
90 # else
91 #define W1 45451
92 #define W2 42813
93 #define W3 38531
94 #define W4 32767
95 #define W5 25746
96 #define W6 17734
97 #define W7 9041
98 
99 #define ROW_SHIFT 16
100 #define COL_SHIFT 17
101 #define DC_SHIFT -1
102 # endif
103 
104 #define MUL(a, b) ((a) * (b))
105 #define MAC(a, b, c) ((a) += (b) * (c))
106 
107 #else
108 
109 #error "Unsupported bitdepth"
110 
111 #endif
112 
113 #ifdef EXTRA_SHIFT
114 static inline void FUNC(idctRowCondDC_extrashift)(int16_t *row, int extra_shift)
115 #else
116 static inline void FUNC6(idctRowCondDC)(idctin *row, int extra_shift)
117 #endif
118 {
119  SUINT a0, a1, a2, a3, b0, b1, b2, b3;
120 
121 // TODO: Add DC-only support for int32_t input
122 #if IN_IDCT_DEPTH == 16
123 #if HAVE_FAST_64BIT
124 #define ROW0_MASK (0xffffLL << 48 * HAVE_BIGENDIAN)
125  if (((AV_RN64A(row) & ~ROW0_MASK) | AV_RN64A(row+4)) == 0) {
126  uint64_t temp;
127  if (DC_SHIFT - extra_shift >= 0) {
128  temp = (row[0] * (1 << (DC_SHIFT - extra_shift))) & 0xffff;
129  } else {
130  temp = ((row[0] + (1<<(extra_shift - DC_SHIFT-1))) >> (extra_shift - DC_SHIFT)) & 0xffff;
131  }
132  temp += temp * (1 << 16);
133  temp += temp * ((uint64_t) 1 << 32);
134  AV_WN64A(row, temp);
135  AV_WN64A(row + 4, temp);
136  return;
137  }
138 #else
139  if (!(AV_RN32A(row+2) |
140  AV_RN32A(row+4) |
141  AV_RN32A(row+6) |
142  row[1])) {
143  uint32_t temp;
144  if (DC_SHIFT - extra_shift >= 0) {
145  temp = (row[0] * (1 << (DC_SHIFT - extra_shift))) & 0xffff;
146  } else {
147  temp = ((row[0] + (1<<(extra_shift - DC_SHIFT-1))) >> (extra_shift - DC_SHIFT)) & 0xffff;
148  }
149  temp += temp * (1 << 16);
150  AV_WN32A(row, temp);
151  AV_WN32A(row+2, temp);
152  AV_WN32A(row+4, temp);
153  AV_WN32A(row+6, temp);
154  return;
155  }
156 #endif
157 #endif
158 
159  a0 = (W4 * row[0]) + (1 << (ROW_SHIFT + extra_shift - 1));
160  a1 = a0;
161  a2 = a0;
162  a3 = a0;
163 
164  a0 += W2 * row[2];
165  a1 += W6 * row[2];
166  a2 -= W6 * row[2];
167  a3 -= W2 * row[2];
168 
169  b0 = MUL(W1, row[1]);
170  MAC(b0, W3, row[3]);
171  b1 = MUL(W3, row[1]);
172  MAC(b1, -W7, row[3]);
173  b2 = MUL(W5, row[1]);
174  MAC(b2, -W1, row[3]);
175  b3 = MUL(W7, row[1]);
176  MAC(b3, -W5, row[3]);
177 
178 #if IN_IDCT_DEPTH == 32
179  if (AV_RN64A(row + 4) | AV_RN64A(row + 6)) {
180 #else
181  if (AV_RN64A(row + 4)) {
182 #endif
183  a0 += W4*row[4] + W6*row[6];
184  a1 += - W4*row[4] - W2*row[6];
185  a2 += - W4*row[4] + W2*row[6];
186  a3 += W4*row[4] - W6*row[6];
187 
188  MAC(b0, W5, row[5]);
189  MAC(b0, W7, row[7]);
190 
191  MAC(b1, -W1, row[5]);
192  MAC(b1, -W5, row[7]);
193 
194  MAC(b2, W7, row[5]);
195  MAC(b2, W3, row[7]);
196 
197  MAC(b3, W3, row[5]);
198  MAC(b3, -W1, row[7]);
199  }
200 
201  row[0] = (int)(a0 + b0) >> (ROW_SHIFT + extra_shift);
202  row[7] = (int)(a0 - b0) >> (ROW_SHIFT + extra_shift);
203  row[1] = (int)(a1 + b1) >> (ROW_SHIFT + extra_shift);
204  row[6] = (int)(a1 - b1) >> (ROW_SHIFT + extra_shift);
205  row[2] = (int)(a2 + b2) >> (ROW_SHIFT + extra_shift);
206  row[5] = (int)(a2 - b2) >> (ROW_SHIFT + extra_shift);
207  row[3] = (int)(a3 + b3) >> (ROW_SHIFT + extra_shift);
208  row[4] = (int)(a3 - b3) >> (ROW_SHIFT + extra_shift);
209 }
210 
211 #define IDCT_COLS do { \
212  a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4)); \
213  a1 = a0; \
214  a2 = a0; \
215  a3 = a0; \
216  \
217  a0 += W2*col[8*2]; \
218  a1 += W6*col[8*2]; \
219  a2 += -W6*col[8*2]; \
220  a3 += -W2*col[8*2]; \
221  \
222  b0 = MUL(W1, col[8*1]); \
223  b1 = MUL(W3, col[8*1]); \
224  b2 = MUL(W5, col[8*1]); \
225  b3 = MUL(W7, col[8*1]); \
226  \
227  MAC(b0, W3, col[8*3]); \
228  MAC(b1, -W7, col[8*3]); \
229  MAC(b2, -W1, col[8*3]); \
230  MAC(b3, -W5, col[8*3]); \
231  \
232  if (col[8*4]) { \
233  a0 += W4*col[8*4]; \
234  a1 += -W4*col[8*4]; \
235  a2 += -W4*col[8*4]; \
236  a3 += W4*col[8*4]; \
237  } \
238  \
239  if (col[8*5]) { \
240  MAC(b0, W5, col[8*5]); \
241  MAC(b1, -W1, col[8*5]); \
242  MAC(b2, W7, col[8*5]); \
243  MAC(b3, W3, col[8*5]); \
244  } \
245  \
246  if (col[8*6]) { \
247  a0 += W6*col[8*6]; \
248  a1 += -W2*col[8*6]; \
249  a2 += W2*col[8*6]; \
250  a3 += -W6*col[8*6]; \
251  } \
252  \
253  if (col[8*7]) { \
254  MAC(b0, W7, col[8*7]); \
255  MAC(b1, -W5, col[8*7]); \
256  MAC(b2, W3, col[8*7]); \
257  MAC(b3, -W1, col[8*7]); \
258  } \
259  } while (0)
260 
261 #ifdef EXTRA_SHIFT
262 static inline void FUNC(idctSparseCol_extrashift)(int16_t *col)
263 #else
264 static inline void FUNC6(idctSparseColPut)(pixel *dest, ptrdiff_t line_size,
265  idctin *col)
266 {
267  SUINT a0, a1, a2, a3, b0, b1, b2, b3;
268 
269  IDCT_COLS;
270 
271  dest[0] = av_clip_pixel((int)(a0 + b0) >> COL_SHIFT);
272  dest += line_size;
273  dest[0] = av_clip_pixel((int)(a1 + b1) >> COL_SHIFT);
274  dest += line_size;
275  dest[0] = av_clip_pixel((int)(a2 + b2) >> COL_SHIFT);
276  dest += line_size;
277  dest[0] = av_clip_pixel((int)(a3 + b3) >> COL_SHIFT);
278  dest += line_size;
279  dest[0] = av_clip_pixel((int)(a3 - b3) >> COL_SHIFT);
280  dest += line_size;
281  dest[0] = av_clip_pixel((int)(a2 - b2) >> COL_SHIFT);
282  dest += line_size;
283  dest[0] = av_clip_pixel((int)(a1 - b1) >> COL_SHIFT);
284  dest += line_size;
285  dest[0] = av_clip_pixel((int)(a0 - b0) >> COL_SHIFT);
286 }
287 
288 static inline void FUNC6(idctSparseColAdd)(pixel *dest, ptrdiff_t line_size,
289  idctin *col)
290 {
291  int a0, a1, a2, a3, b0, b1, b2, b3;
292 
293  IDCT_COLS;
294 
295  dest[0] = av_clip_pixel(dest[0] + ((a0 + b0) >> COL_SHIFT));
296  dest += line_size;
297  dest[0] = av_clip_pixel(dest[0] + ((a1 + b1) >> COL_SHIFT));
298  dest += line_size;
299  dest[0] = av_clip_pixel(dest[0] + ((a2 + b2) >> COL_SHIFT));
300  dest += line_size;
301  dest[0] = av_clip_pixel(dest[0] + ((a3 + b3) >> COL_SHIFT));
302  dest += line_size;
303  dest[0] = av_clip_pixel(dest[0] + ((a3 - b3) >> COL_SHIFT));
304  dest += line_size;
305  dest[0] = av_clip_pixel(dest[0] + ((a2 - b2) >> COL_SHIFT));
306  dest += line_size;
307  dest[0] = av_clip_pixel(dest[0] + ((a1 - b1) >> COL_SHIFT));
308  dest += line_size;
309  dest[0] = av_clip_pixel(dest[0] + ((a0 - b0) >> COL_SHIFT));
310 }
311 
312 static inline void FUNC6(idctSparseCol)(idctin *col)
313 #endif
314 {
315  int a0, a1, a2, a3, b0, b1, b2, b3;
316 
317  IDCT_COLS;
318 
319  col[0 ] = ((a0 + b0) >> COL_SHIFT);
320  col[8 ] = ((a1 + b1) >> COL_SHIFT);
321  col[16] = ((a2 + b2) >> COL_SHIFT);
322  col[24] = ((a3 + b3) >> COL_SHIFT);
323  col[32] = ((a3 - b3) >> COL_SHIFT);
324  col[40] = ((a2 - b2) >> COL_SHIFT);
325  col[48] = ((a1 - b1) >> COL_SHIFT);
326  col[56] = ((a0 - b0) >> COL_SHIFT);
327 }
328 
329 #ifndef EXTRA_SHIFT
330 void FUNC6(ff_simple_idct_put)(uint8_t *dest_, ptrdiff_t line_size, int16_t *block_)
331 {
332  idctin *block = (idctin *)block_;
333  pixel *dest = (pixel *)dest_;
334  int i;
335 
336  line_size /= sizeof(pixel);
337 
338  for (i = 0; i < 8; i++)
339  FUNC6(idctRowCondDC)(block + i*8, 0);
340 
341  for (i = 0; i < 8; i++)
342  FUNC6(idctSparseColPut)(dest + i, line_size, block + i);
343 }
344 
345 #if IN_IDCT_DEPTH == 16
346 void FUNC6(ff_simple_idct_add)(uint8_t *dest_, ptrdiff_t line_size, int16_t *block)
347 {
348  pixel *dest = (pixel *)dest_;
349  int i;
350 
351  line_size /= sizeof(pixel);
352 
353  for (i = 0; i < 8; i++)
354  FUNC6(idctRowCondDC)(block + i*8, 0);
355 
356  for (i = 0; i < 8; i++)
357  FUNC6(idctSparseColAdd)(dest + i, line_size, block + i);
358 }
359 
360 void FUNC6(ff_simple_idct)(int16_t *block)
361 {
362  int i;
363 
364  for (i = 0; i < 8; i++)
365  FUNC6(idctRowCondDC)(block + i*8, 0);
366 
367  for (i = 0; i < 8; i++)
368  FUNC6(idctSparseCol)(block + i);
369 }
370 #endif
371 #endif
void FUNC6() ff_simple_idct_put(uint8_t *dest_, ptrdiff_t line_size, int16_t *block_)
#define W6
static void FUNC6() idctRowCondDC(idctin *row, int extra_shift)
else temp
Definition: vf_mcdeint.c:256
#define a0
Definition: regdef.h:46
static void FUNC6() idctSparseCol(idctin *col)
#define a1
Definition: regdef.h:47
#define SUINT
#define AV_WN32A(p, v)
Definition: intreadwrite.h:538
#define W2
#define W5
#define av_clip_pixel(a)
#define AV_RN32A(p)
Definition: intreadwrite.h:526
static int16_t block[64]
Definition: dct.c:115
#define a3
Definition: regdef.h:49
#define W1
#define ROW_SHIFT
uint8_t
#define FUNC6(a)
static void FUNC6() idctSparseColAdd(pixel *dest, ptrdiff_t line_size, idctin *col)
#define W7
#define FUNC(a)
#define W3
#define a2
Definition: regdef.h:48
#define W4
#define AV_WN64A(p, v)
Definition: intreadwrite.h:542
#define MUL(a, b)
#define COL_SHIFT
#define IDCT_COLS
uint8_t pixel
Definition: tiny_ssim.c:42
#define idctin
int
simple idct header.
static void FUNC6() idctSparseColPut(pixel *dest, ptrdiff_t line_size, idctin *col)
#define AV_RN64A(p)
Definition: intreadwrite.h:530