1// Copyright 2010 Google Inc.
2//
3// This code is licensed under the same terms as WebM:
4//  Software License Agreement:  http://www.webmproject.org/license/software/
5//  Additional IP Rights Grant:  http://www.webmproject.org/license/additional/
6// -----------------------------------------------------------------------------
7//
8// speed-critical functions.
9//
10// Author: Skal (pascal.massimino@gmail.com)
11
12#include "vp8i.h"
13
14#if defined(__cplusplus) || defined(c_plusplus)
15extern "C" {
16#endif
17
18//-----------------------------------------------------------------------------
19// run-time tables (~4k)
20
21static uint8_t abs0[255 + 255 + 1];     // abs(i)
22static uint8_t abs1[255 + 255 + 1];     // abs(i)>>1
23static int8_t sclip1[1020 + 1020 + 1];  // clips [-1020, 1020] to [-128, 127]
24static int8_t sclip2[112 + 112 + 1];    // clips [-112, 112] to [-16, 15]
25static uint8_t clip1[255 + 510 + 1];    // clips [-255,510] to [0,255]
26
27// We declare this variable 'volatile' to prevent instruction reordering
28// and make sure it's set to true _last_ (so as to be thread-safe)
29static volatile int tables_ok = 0;
30
31void VP8DspInitTables(void) {
32  if (!tables_ok) {
33    int i;
34    for (i = -255; i <= 255; ++i) {
35      abs0[255 + i] = (i < 0) ? -i : i;
36      abs1[255 + i] = abs0[255 + i] >> 1;
37    }
38    for (i = -1020; i <= 1020; ++i) {
39      sclip1[1020 + i] = (i < -128) ? -128 : (i > 127) ? 127 : i;
40    }
41    for (i = -112; i <= 112; ++i) {
42      sclip2[112 + i] = (i < -16) ? -16 : (i > 15) ? 15 : i;
43    }
44    for (i = -255; i <= 255 + 255; ++i) {
45      clip1[255 + i] = (i < 0) ? 0 : (i > 255) ? 255 : i;
46    }
47    tables_ok = 1;
48  }
49}
50
51static inline uint8_t clip_8b(int v) {
52  return (!(v & ~0xff)) ? v : (v < 0) ? 0 : 255;
53}
54
55//-----------------------------------------------------------------------------
56// Transforms (Paragraph 14.4)
57
58#define STORE(x, y, v) \
59  dst[x + y * BPS] = clip_8b(dst[x + y * BPS] + ((v) >> 3))
60
61static const int kC1 = 20091 + (1 << 16);
62static const int kC2 = 35468;
63#define MUL(a, b) (((a) * (b)) >> 16)
64
65static void TransformOne(const int16_t* in, uint8_t* dst) {
66  int C[4 * 4], *tmp;
67  int i;
68  tmp = C;
69  for (i = 0; i < 4; ++i) {    // vertical pass
70    const int a = in[0] + in[8];    // [-4096, 4094]
71    const int b = in[0] - in[8];    // [-4095, 4095]
72    const int c = MUL(in[4], kC2) - MUL(in[12], kC1);   // [-3783, 3783]
73    const int d = MUL(in[4], kC1) + MUL(in[12], kC2);   // [-3785, 3781]
74    tmp[0] = a + d;   // [-7881, 7875]
75    tmp[1] = b + c;   // [-7878, 7878]
76    tmp[2] = b - c;   // [-7878, 7878]
77    tmp[3] = a - d;   // [-7877, 7879]
78    tmp += 4;
79    in++;
80  }
81  // Each pass is expanding the dynamic range by ~3.85 (upper bound).
82  // The exact value is (2. + (kC1 + kC2) / 65536).
83  // After the second pass, maximum interval is [-3794, 3794], assuming
84  // an input in [-2048, 2047] interval. We then need to add a dst value
85  // in the [0, 255] range.
86  // In the worst case scenario, the input to clip_8b() can be as large as
87  // [-60713, 60968].
88  tmp = C;
89  for (i = 0; i < 4; ++i) {    // horizontal pass
90    const int dc = tmp[0] + 4;
91    const int a =  dc +  tmp[8];
92    const int b =  dc -  tmp[8];
93    const int c = MUL(tmp[4], kC2) - MUL(tmp[12], kC1);
94    const int d = MUL(tmp[4], kC1) + MUL(tmp[12], kC2);
95    STORE(0, 0, a + d);
96    STORE(1, 0, b + c);
97    STORE(2, 0, b - c);
98    STORE(3, 0, a - d);
99    tmp++;
100    dst += BPS;
101  }
102}
103#undef MUL
104
105static void TransformTwo(const int16_t* in, uint8_t* dst, int do_two) {
106  TransformOne(in, dst);
107  if (do_two) {
108    TransformOne(in + 16, dst + 4);
109  }
110}
111
112static void TransformUV(const int16_t* in, uint8_t* dst) {
113  VP8Transform(in + 0 * 16, dst, 1);
114  VP8Transform(in + 2 * 16, dst + 4 * BPS, 1);
115}
116
117static void TransformDC(const int16_t *in, uint8_t* dst) {
118  const int DC = in[0] + 4;
119  int i, j;
120  for (j = 0; j < 4; ++j) {
121    for (i = 0; i < 4; ++i) {
122      STORE(i, j, DC);
123    }
124  }
125}
126
127static void TransformDCUV(const int16_t* in, uint8_t* dst) {
128  if (in[0 * 16]) TransformDC(in + 0 * 16, dst);
129  if (in[1 * 16]) TransformDC(in + 1 * 16, dst + 4);
130  if (in[2 * 16]) TransformDC(in + 2 * 16, dst + 4 * BPS);
131  if (in[3 * 16]) TransformDC(in + 3 * 16, dst + 4 * BPS + 4);
132}
133
134#undef STORE
135
136// default C implementations:
137VP8Idct2 VP8Transform = TransformTwo;
138VP8Idct VP8TransformUV = TransformUV;
139VP8Idct VP8TransformDC = TransformDC;
140VP8Idct VP8TransformDCUV = TransformDCUV;
141
142//-----------------------------------------------------------------------------
143// Paragraph 14.3
144
145static void TransformWHT(const int16_t* in, int16_t* out) {
146  int tmp[16];
147  int i;
148  for (i = 0; i < 4; ++i) {
149    const int a0 = in[0 + i] + in[12 + i];
150    const int a1 = in[4 + i] + in[ 8 + i];
151    const int a2 = in[4 + i] - in[ 8 + i];
152    const int a3 = in[0 + i] - in[12 + i];
153    tmp[0  + i] = a0 + a1;
154    tmp[8  + i] = a0 - a1;
155    tmp[4  + i] = a3 + a2;
156    tmp[12 + i] = a3 - a2;
157  }
158  for (i = 0; i < 4; ++i) {
159    const int dc = tmp[0 + i * 4] + 3;    // w/ rounder
160    const int a0 = dc             + tmp[3 + i * 4];
161    const int a1 = tmp[1 + i * 4] + tmp[2 + i * 4];
162    const int a2 = tmp[1 + i * 4] - tmp[2 + i * 4];
163    const int a3 = dc             - tmp[3 + i * 4];
164    out[ 0] = (a0 + a1) >> 3;
165    out[16] = (a3 + a2) >> 3;
166    out[32] = (a0 - a1) >> 3;
167    out[48] = (a3 - a2) >> 3;
168    out += 64;
169  }
170}
171
172void (*VP8TransformWHT)(const int16_t* in, int16_t* out) = TransformWHT;
173
174//-----------------------------------------------------------------------------
175// Intra predictions
176
177#define OUT(x, y) dst[(x) + (y) * BPS]
178
179static inline void TrueMotion(uint8_t *dst, int size) {
180  const uint8_t* top = dst - BPS;
181  const uint8_t* const clip0 = clip1 + 255 - top[-1];
182  int y;
183  for (y = 0; y < size; ++y) {
184    const uint8_t* const clip = clip0 + dst[-1];
185    int x;
186    for (x = 0; x < size; ++x) {
187      dst[x] = clip[top[x]];
188    }
189    dst += BPS;
190  }
191}
192static void TM4(uint8_t *dst)   { TrueMotion(dst, 4); }
193static void TM8uv(uint8_t *dst) { TrueMotion(dst, 8); }
194static void TM16(uint8_t *dst)  { TrueMotion(dst, 16); }
195
196//-----------------------------------------------------------------------------
197// 16x16
198
199static void VE16(uint8_t *dst) {     // vertical
200  int j;
201  for (j = 0; j < 16; ++j) {
202    memcpy(dst + j * BPS, dst - BPS, 16);
203  }
204}
205
206static void HE16(uint8_t *dst) {     // horizontal
207  int j;
208  for (j = 16; j > 0; --j) {
209    memset(dst, dst[-1], 16);
210    dst += BPS;
211  }
212}
213
214static inline void Put16(int v, uint8_t* dst) {
215  int j;
216  for (j = 0; j < 16; ++j) {
217    memset(dst + j * BPS, v, 16);
218  }
219}
220
221static void DC16(uint8_t *dst) {    // DC
222  int DC = 16;
223  int j;
224  for (j = 0; j < 16; ++j) {
225    DC += dst[-1 + j * BPS] + dst[j - BPS];
226  }
227  Put16(DC >> 5, dst);
228}
229
230static void DC16NoTop(uint8_t *dst) {   // DC with top samples not available
231  int DC = 8;
232  int j;
233  for (j = 0; j < 16; ++j) {
234    DC += dst[-1 + j * BPS];
235  }
236  Put16(DC >> 4, dst);
237}
238
239static void DC16NoLeft(uint8_t *dst) {  // DC with left samples not available
240  int DC = 8;
241  int i;
242  for (i = 0; i < 16; ++i) {
243    DC += dst[i - BPS];
244  }
245  Put16(DC >> 4, dst);
246}
247
248static void DC16NoTopLeft(uint8_t *dst) {  // DC with no top and left samples
249  Put16(0x80, dst);
250}
251
252//-----------------------------------------------------------------------------
253// 4x4
254
255#define AVG3(a, b, c) (((a) + 2 * (b) + (c) + 2) >> 2)
256#define AVG2(a, b) (((a) + (b) + 1) >> 1)
257
258static void VE4(uint8_t *dst) {    // vertical
259  const uint8_t* top = dst - BPS;
260  const uint8_t vals[4] = {
261    AVG3(top[-1], top[0], top[1]),
262    AVG3(top[ 0], top[1], top[2]),
263    AVG3(top[ 1], top[2], top[3]),
264    AVG3(top[ 2], top[3], top[4])
265  };
266  int i;
267  for (i = 0; i < 4; ++i) {
268    memcpy(dst + i * BPS, vals, sizeof(vals));
269  }
270}
271
272static void HE4(uint8_t *dst) {    // horizontal
273  const int A = dst[-1 - BPS];
274  const int B = dst[-1];
275  const int C = dst[-1 + BPS];
276  const int D = dst[-1 + 2 * BPS];
277  const int E = dst[-1 + 3 * BPS];
278  *(uint32_t*)(dst + 0 * BPS) = 0x01010101U * AVG3(A, B, C);
279  *(uint32_t*)(dst + 1 * BPS) = 0x01010101U * AVG3(B, C, D);
280  *(uint32_t*)(dst + 2 * BPS) = 0x01010101U * AVG3(C, D, E);
281  *(uint32_t*)(dst + 3 * BPS) = 0x01010101U * AVG3(D, E, E);
282}
283
284static void DC4(uint8_t *dst) {   // DC
285  uint32_t dc = 4;
286  int i;
287  for (i = 0; i < 4; ++i) dc += dst[i - BPS] + dst[-1 + i * BPS];
288  dc >>= 3;
289  for (i = 0; i < 4; ++i) memset(dst + i * BPS, dc, 4);
290}
291
292static void RD4(uint8_t *dst) {   // Down-right
293  const int I = dst[-1 + 0 * BPS];
294  const int J = dst[-1 + 1 * BPS];
295  const int K = dst[-1 + 2 * BPS];
296  const int L = dst[-1 + 3 * BPS];
297  const int X = dst[-1 - BPS];
298  const int A = dst[0 - BPS];
299  const int B = dst[1 - BPS];
300  const int C = dst[2 - BPS];
301  const int D = dst[3 - BPS];
302  OUT(0, 3)                                     = AVG3(J, K, L);
303  OUT(0, 2) = OUT(1, 3)                         = AVG3(I, J, K);
304  OUT(0, 1) = OUT(1, 2) = OUT(2, 3)             = AVG3(X, I, J);
305  OUT(0, 0) = OUT(1, 1) = OUT(2, 2) = OUT(3, 3) = AVG3(A, X, I);
306  OUT(1, 0) = OUT(2, 1) = OUT(3, 2)             = AVG3(B, A, X);
307  OUT(2, 0) = OUT(3, 1)                         = AVG3(C, B, A);
308  OUT(3, 0)                                     = AVG3(D, C, B);
309}
310
311static void LD4(uint8_t *dst) {   // Down-Left
312  const int A = dst[0 - BPS];
313  const int B = dst[1 - BPS];
314  const int C = dst[2 - BPS];
315  const int D = dst[3 - BPS];
316  const int E = dst[4 - BPS];
317  const int F = dst[5 - BPS];
318  const int G = dst[6 - BPS];
319  const int H = dst[7 - BPS];
320  OUT(0, 0)                                     = AVG3(A, B, C);
321  OUT(1, 0) = OUT(0, 1)                         = AVG3(B, C, D);
322  OUT(2, 0) = OUT(1, 1) = OUT(0, 2)             = AVG3(C, D, E);
323  OUT(3, 0) = OUT(2, 1) = OUT(1, 2) = OUT(0, 3) = AVG3(D, E, F);
324  OUT(3, 1) = OUT(2, 2) = OUT(1, 3)             = AVG3(E, F, G);
325  OUT(3, 2) = OUT(2, 3)                         = AVG3(F, G, H);
326  OUT(3, 3)                                     = AVG3(G, H, H);
327}
328
329static void VR4(uint8_t *dst) {   // Vertical-Right
330  const int I = dst[-1 + 0 * BPS];
331  const int J = dst[-1 + 1 * BPS];
332  const int K = dst[-1 + 2 * BPS];
333  const int X = dst[-1 - BPS];
334  const int A = dst[0 - BPS];
335  const int B = dst[1 - BPS];
336  const int C = dst[2 - BPS];
337  const int D = dst[3 - BPS];
338  OUT(0, 0) = OUT(1, 2) = AVG2(X, A);
339  OUT(1, 0) = OUT(2, 2) = AVG2(A, B);
340  OUT(2, 0) = OUT(3, 2) = AVG2(B, C);
341  OUT(3, 0)             = AVG2(C, D);
342
343  OUT(0, 3) =             AVG3(K, J, I);
344  OUT(0, 2) =             AVG3(J, I, X);
345  OUT(0, 1) = OUT(1, 3) = AVG3(I, X, A);
346  OUT(1, 1) = OUT(2, 3) = AVG3(X, A, B);
347  OUT(2, 1) = OUT(3, 3) = AVG3(A, B, C);
348  OUT(3, 1) =             AVG3(B, C, D);
349}
350
351static void VL4(uint8_t *dst) {   // Vertical-Left
352  const int A = dst[0 - BPS];
353  const int B = dst[1 - BPS];
354  const int C = dst[2 - BPS];
355  const int D = dst[3 - BPS];
356  const int E = dst[4 - BPS];
357  const int F = dst[5 - BPS];
358  const int G = dst[6 - BPS];
359  const int H = dst[7 - BPS];
360  OUT(0, 0) =             AVG2(A, B);
361  OUT(1, 0) = OUT(0, 2) = AVG2(B, C);
362  OUT(2, 0) = OUT(1, 2) = AVG2(C, D);
363  OUT(3, 0) = OUT(2, 2) = AVG2(D, E);
364
365  OUT(0, 1) =             AVG3(A, B, C);
366  OUT(1, 1) = OUT(0, 3) = AVG3(B, C, D);
367  OUT(2, 1) = OUT(1, 3) = AVG3(C, D, E);
368  OUT(3, 1) = OUT(2, 3) = AVG3(D, E, F);
369              OUT(3, 2) = AVG3(E, F, G);
370              OUT(3, 3) = AVG3(F, G, H);
371}
372
373static void HU4(uint8_t *dst) {   // Horizontal-Up
374  const int I = dst[-1 + 0 * BPS];
375  const int J = dst[-1 + 1 * BPS];
376  const int K = dst[-1 + 2 * BPS];
377  const int L = dst[-1 + 3 * BPS];
378  OUT(0, 0) =             AVG2(I, J);
379  OUT(2, 0) = OUT(0, 1) = AVG2(J, K);
380  OUT(2, 1) = OUT(0, 2) = AVG2(K, L);
381  OUT(1, 0) =             AVG3(I, J, K);
382  OUT(3, 0) = OUT(1, 1) = AVG3(J, K, L);
383  OUT(3, 1) = OUT(1, 2) = AVG3(K, L, L);
384  OUT(3, 2) = OUT(2, 2) =
385    OUT(0, 3) = OUT(1, 3) = OUT(2, 3) = OUT(3, 3) = L;
386}
387
388static void HD4(uint8_t *dst) {  // Horizontal-Down
389  const int I = dst[-1 + 0 * BPS];
390  const int J = dst[-1 + 1 * BPS];
391  const int K = dst[-1 + 2 * BPS];
392  const int L = dst[-1 + 3 * BPS];
393  const int X = dst[-1 - BPS];
394  const int A = dst[0 - BPS];
395  const int B = dst[1 - BPS];
396  const int C = dst[2 - BPS];
397
398  OUT(0, 0) = OUT(2, 1) = AVG2(I, X);
399  OUT(0, 1) = OUT(2, 2) = AVG2(J, I);
400  OUT(0, 2) = OUT(2, 3) = AVG2(K, J);
401  OUT(0, 3)             = AVG2(L, K);
402
403  OUT(3, 0)             = AVG3(A, B, C);
404  OUT(2, 0)             = AVG3(X, A, B);
405  OUT(1, 0) = OUT(3, 1) = AVG3(I, X, A);
406  OUT(1, 1) = OUT(3, 2) = AVG3(J, I, X);
407  OUT(1, 2) = OUT(3, 3) = AVG3(K, J, I);
408  OUT(1, 3)             = AVG3(L, K, J);
409}
410
411#undef AVG3
412#undef AVG2
413
414//-----------------------------------------------------------------------------
415// Chroma
416
417static void VE8uv(uint8_t *dst) {    // vertical
418  int j;
419  for (j = 0; j < 8; ++j) {
420    memcpy(dst + j * BPS, dst - BPS, 8);
421  }
422}
423
424static void HE8uv(uint8_t *dst) {    // horizontal
425  int j;
426  for (j = 0; j < 8; ++j) {
427    memset(dst, dst[-1], 8);
428    dst += BPS;
429  }
430}
431
432// helper for chroma-DC predictions
433static inline void Put8x8uv(uint64_t v, uint8_t* dst) {
434  int j;
435  for (j = 0; j < 8; ++j) {
436    *(uint64_t*)(dst + j * BPS) = v;
437  }
438}
439
440static void DC8uv(uint8_t *dst) {     // DC
441  int dc0 = 8;
442  int i;
443  for (i = 0; i < 8; ++i) {
444    dc0 += dst[i - BPS] + dst[-1 + i * BPS];
445  }
446  Put8x8uv((uint64_t)((dc0 >> 4) * 0x0101010101010101ULL), dst);
447}
448
449static void DC8uvNoLeft(uint8_t *dst) {   // DC with no left samples
450  int dc0 = 4;
451  int i;
452  for (i = 0; i < 8; ++i) {
453    dc0 += dst[i - BPS];
454  }
455  Put8x8uv((uint64_t)((dc0 >> 3) * 0x0101010101010101ULL), dst);
456}
457
458static void DC8uvNoTop(uint8_t *dst) {  // DC with no top samples
459  int dc0 = 4;
460  int i;
461  for (i = 0; i < 8; ++i) {
462    dc0 += dst[-1 + i * BPS];
463  }
464  Put8x8uv((uint64_t)((dc0 >> 3) * 0x0101010101010101ULL), dst);
465}
466
467static void DC8uvNoTopLeft(uint8_t *dst) {    // DC with nothing
468  Put8x8uv(0x8080808080808080ULL, dst);
469}
470
471//-----------------------------------------------------------------------------
472// default C implementations
473
474VP8PredFunc VP8PredLuma4[NUM_BMODES] = {
475  DC4, TM4, VE4, HE4, RD4, VR4, LD4, VL4, HD4, HU4
476};
477
478VP8PredFunc VP8PredLuma16[NUM_B_DC_MODES] = {
479  DC16, TM16, VE16, HE16,
480  DC16NoTop, DC16NoLeft, DC16NoTopLeft
481};
482
483VP8PredFunc VP8PredChroma8[NUM_B_DC_MODES] = {
484  DC8uv, TM8uv, VE8uv, HE8uv,
485  DC8uvNoTop, DC8uvNoLeft, DC8uvNoTopLeft
486};
487
488//-----------------------------------------------------------------------------
489// Edge filtering functions
490
491// 4 pixels in, 2 pixels out
492static inline void do_filter2(uint8_t* p, int step) {
493  const int p1 = p[-2*step], p0 = p[-step], q0 = p[0], q1 = p[step];
494  const int a = 3 * (q0 - p0) + sclip1[1020 + p1 - q1];
495  const int a1 = sclip2[112 + ((a + 4) >> 3)];
496  const int a2 = sclip2[112 + ((a + 3) >> 3)];
497  p[-step] = clip1[255 + p0 + a2];
498  p[    0] = clip1[255 + q0 - a1];
499}
500
501// 4 pixels in, 4 pixels out
502static inline void do_filter4(uint8_t* p, int step) {
503  const int p1 = p[-2*step], p0 = p[-step], q0 = p[0], q1 = p[step];
504  const int a = 3 * (q0 - p0);
505  const int a1 = sclip2[112 + ((a + 4) >> 3)];
506  const int a2 = sclip2[112 + ((a + 3) >> 3)];
507  const int a3 = (a1 + 1) >> 1;
508  p[-2*step] = clip1[255 + p1 + a3];
509  p[-  step] = clip1[255 + p0 + a2];
510  p[      0] = clip1[255 + q0 - a1];
511  p[   step] = clip1[255 + q1 - a3];
512}
513
514// 6 pixels in, 6 pixels out
515static inline void do_filter6(uint8_t* p, int step) {
516  const int p2 = p[-3*step], p1 = p[-2*step], p0 = p[-step];
517  const int q0 = p[0], q1 = p[step], q2 = p[2*step];
518  const int a = sclip1[1020 + 3 * (q0 - p0) + sclip1[1020 + p1 - q1]];
519  const int a1 = (27 * a + 63) >> 7;  // eq. to ((3 * a + 7) * 9) >> 7
520  const int a2 = (18 * a + 63) >> 7;  // eq. to ((2 * a + 7) * 9) >> 7
521  const int a3 = (9  * a + 63) >> 7;  // eq. to ((1 * a + 7) * 9) >> 7
522  p[-3*step] = clip1[255 + p2 + a3];
523  p[-2*step] = clip1[255 + p1 + a2];
524  p[-  step] = clip1[255 + p0 + a1];
525  p[      0] = clip1[255 + q0 - a1];
526  p[   step] = clip1[255 + q1 - a2];
527  p[ 2*step] = clip1[255 + q2 - a3];
528}
529
530static inline int hev(const uint8_t* p, int step, int thresh) {
531  const int p1 = p[-2*step], p0 = p[-step], q0 = p[0], q1 = p[step];
532  return (abs0[255 + p1 - p0] > thresh) || (abs0[255 + q1 - q0] > thresh);
533}
534
535static inline int needs_filter(const uint8_t* p, int step, int thresh) {
536  const int p1 = p[-2*step], p0 = p[-step], q0 = p[0], q1 = p[step];
537  return (2 * abs0[255 + p0 - q0] + abs1[255 + p1 - q1]) <= thresh;
538}
539
540static inline int needs_filter2(const uint8_t* p, int step, int t, int it) {
541  const int p3 = p[-4*step], p2 = p[-3*step], p1 = p[-2*step], p0 = p[-step];
542  const int q0 = p[0], q1 = p[step], q2 = p[2*step], q3 = p[3*step];
543  if ((2 * abs0[255 + p0 - q0] + abs1[255 + p1 - q1]) > t)
544    return 0;
545  return abs0[255 + p3 - p2] <= it && abs0[255 + p2 - p1] <= it &&
546         abs0[255 + p1 - p0] <= it && abs0[255 + q3 - q2] <= it &&
547         abs0[255 + q2 - q1] <= it && abs0[255 + q1 - q0] <= it;
548}
549
550//-----------------------------------------------------------------------------
551// Simple In-loop filtering (Paragraph 15.2)
552
553static void SimpleVFilter16(uint8_t* p, int stride, int thresh) {
554  int i;
555  for (i = 0; i < 16; ++i) {
556    if (needs_filter(p + i, stride, thresh)) {
557      do_filter2(p + i, stride);
558    }
559  }
560}
561
562static void SimpleHFilter16(uint8_t* p, int stride, int thresh) {
563  int i;
564  for (i = 0; i < 16; ++i) {
565    if (needs_filter(p + i * stride, 1, thresh)) {
566      do_filter2(p + i * stride, 1);
567    }
568  }
569}
570
571static void SimpleVFilter16i(uint8_t* p, int stride, int thresh) {
572  int k;
573  for (k = 3; k > 0; --k) {
574    p += 4 * stride;
575    SimpleVFilter16(p, stride, thresh);
576  }
577}
578
579static void SimpleHFilter16i(uint8_t* p, int stride, int thresh) {
580  int k;
581  for (k = 3; k > 0; --k) {
582    p += 4;
583    SimpleHFilter16(p, stride, thresh);
584  }
585}
586
587//-----------------------------------------------------------------------------
588// Complex In-loop filtering (Paragraph 15.3)
589
590static inline void FilterLoop26(uint8_t* p, int hstride, int vstride, int size,
591                                int thresh, int ithresh, int hev_thresh) {
592  while (size-- > 0) {
593    if (needs_filter2(p, hstride, thresh, ithresh)) {
594      if (hev(p, hstride, hev_thresh)) {
595        do_filter2(p, hstride);
596      } else {
597        do_filter6(p, hstride);
598      }
599    }
600    p += vstride;
601  }
602}
603
604static inline void FilterLoop24(uint8_t* p, int hstride, int vstride, int size,
605                                int thresh, int ithresh, int hev_thresh) {
606  while (size-- > 0) {
607    if (needs_filter2(p, hstride, thresh, ithresh)) {
608      if (hev(p, hstride, hev_thresh)) {
609        do_filter2(p, hstride);
610      } else {
611        do_filter4(p, hstride);
612      }
613    }
614    p += vstride;
615  }
616}
617
618// on macroblock edges
619static void VFilter16(uint8_t* p, int stride,
620                      int thresh, int ithresh, int hev_thresh) {
621  FilterLoop26(p, stride, 1, 16, thresh, ithresh, hev_thresh);
622}
623
624static void HFilter16(uint8_t* p, int stride,
625                      int thresh, int ithresh, int hev_thresh) {
626  FilterLoop26(p, 1, stride, 16, thresh, ithresh, hev_thresh);
627}
628
629// on three inner edges
630static void VFilter16i(uint8_t* p, int stride,
631                       int thresh, int ithresh, int hev_thresh) {
632  int k;
633  for (k = 3; k > 0; --k) {
634    p += 4 * stride;
635    FilterLoop24(p, stride, 1, 16, thresh, ithresh, hev_thresh);
636  }
637}
638
639static void HFilter16i(uint8_t* p, int stride,
640                       int thresh, int ithresh, int hev_thresh) {
641  int k;
642  for (k = 3; k > 0; --k) {
643    p += 4;
644    FilterLoop24(p, 1, stride, 16, thresh, ithresh, hev_thresh);
645  }
646}
647
648// 8-pixels wide variant, for chroma filtering
649static void VFilter8(uint8_t* u, uint8_t* v, int stride,
650                     int thresh, int ithresh, int hev_thresh) {
651  FilterLoop26(u, stride, 1, 8, thresh, ithresh, hev_thresh);
652  FilterLoop26(v, stride, 1, 8, thresh, ithresh, hev_thresh);
653}
654
655static void HFilter8(uint8_t* u, uint8_t* v, int stride,
656                     int thresh, int ithresh, int hev_thresh) {
657  FilterLoop26(u, 1, stride, 8, thresh, ithresh, hev_thresh);
658  FilterLoop26(v, 1, stride, 8, thresh, ithresh, hev_thresh);
659}
660
661static void VFilter8i(uint8_t* u, uint8_t* v, int stride,
662                      int thresh, int ithresh, int hev_thresh) {
663  FilterLoop24(u + 4 * stride, stride, 1, 8, thresh, ithresh, hev_thresh);
664  FilterLoop24(v + 4 * stride, stride, 1, 8, thresh, ithresh, hev_thresh);
665}
666
667static void HFilter8i(uint8_t* u, uint8_t* v, int stride,
668                      int thresh, int ithresh, int hev_thresh) {
669  FilterLoop24(u + 4, 1, stride, 8, thresh, ithresh, hev_thresh);
670  FilterLoop24(v + 4, 1, stride, 8, thresh, ithresh, hev_thresh);
671}
672
673//-----------------------------------------------------------------------------
674
675void (*VP8VFilter16)(uint8_t*, int, int, int, int) = VFilter16;
676void (*VP8HFilter16)(uint8_t*, int, int, int, int) = HFilter16;
677void (*VP8VFilter8)(uint8_t*, uint8_t*, int, int, int, int) = VFilter8;
678void (*VP8HFilter8)(uint8_t*, uint8_t*, int, int, int, int) = HFilter8;
679void (*VP8VFilter16i)(uint8_t*, int, int, int, int) = VFilter16i;
680void (*VP8HFilter16i)(uint8_t*, int, int, int, int) = HFilter16i;
681void (*VP8VFilter8i)(uint8_t*, uint8_t*, int, int, int, int) = VFilter8i;
682void (*VP8HFilter8i)(uint8_t*, uint8_t*, int, int, int, int) = HFilter8i;
683
684void (*VP8SimpleVFilter16)(uint8_t*, int, int) = SimpleVFilter16;
685void (*VP8SimpleHFilter16)(uint8_t*, int, int) = SimpleHFilter16;
686void (*VP8SimpleVFilter16i)(uint8_t*, int, int) = SimpleVFilter16i;
687void (*VP8SimpleHFilter16i)(uint8_t*, int, int) = SimpleHFilter16i;
688
689//-----------------------------------------------------------------------------
690// SSE2 detection.
691//
692
693#if defined(__pic__) && defined(__i386__)
694static inline void GetCPUInfo(int cpu_info[4], int info_type) {
695  __asm__ volatile (
696    "mov %%ebx, %%edi\n"
697    "cpuid\n"
698    "xchg %%edi, %%ebx\n"
699    : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
700    : "a"(info_type));
701}
702#elif defined(__i386__) || defined(__x86_64__)
703static inline void GetCPUInfo(int cpu_info[4], int info_type) {
704  __asm__ volatile (
705    "cpuid\n"
706    : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
707    : "a"(info_type));
708}
709#elif defined(_MSC_VER)  // Visual C++
710#define GetCPUInfo __cpuid
711#endif
712
713#if defined(__i386__) || defined(__x86_64__) || defined(_MSC_VER)
714static int x86CPUInfo(CPUFeature feature) {
715  int cpu_info[4];
716  GetCPUInfo(cpu_info, 1);
717  if (feature == kSSE2) {
718    return 0 != (cpu_info[3] & 0x04000000);
719  }
720  if (feature == kSSE3) {
721    return 0 != (cpu_info[2] & 0x00000001);
722  }
723  return 0;
724}
725VP8CPUInfo VP8DecGetCPUInfo = x86CPUInfo;
726#else
727VP8CPUInfo VP8DecGetCPUInfo = NULL;
728#endif
729
730//-----------------------------------------------------------------------------
731
732extern void VP8DspInitSSE2(void);
733
734void VP8DspInit(void) {
735  // If defined, use CPUInfo() to overwrite some pointers with faster versions.
736  if (VP8DecGetCPUInfo) {
737    if (VP8DecGetCPUInfo(kSSE2)) {
738#if defined(__SSE2__) || defined(_MSC_VER)
739      VP8DspInitSSE2();
740#endif
741    }
742    if (VP8DecGetCPUInfo(kSSE3)) {
743      // later we'll plug some SSE3 variant here
744    }
745  }
746}
747
748#if defined(__cplusplus) || defined(c_plusplus)
749}    // extern "C"
750#endif
751