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[chromium-blink-merge.git] / third_party / libwebp / dsp / enc.c
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1 // Copyright 2011 Google Inc. All Rights Reserved.
2 //
3 // Use of this source code is governed by a BSD-style license
4 // that can be found in the COPYING file in the root of the source
5 // tree. An additional intellectual property rights grant can be found
6 // in the file PATENTS. All contributing project authors may
7 // be found in the AUTHORS file in the root of the source tree.
8 // -----------------------------------------------------------------------------
9 //
10 // Speed-critical encoding functions.
12 // Author: Skal (pascal.massimino@gmail.com)
14 #include <assert.h>
15 #include <stdlib.h> // for abs()
17 #include "./dsp.h"
18 #include "../enc/vp8enci.h"
20 static WEBP_INLINE uint8_t clip_8b(int v) {
21 return (!(v & ~0xff)) ? v : (v < 0) ? 0 : 255;
24 static WEBP_INLINE int clip_max(int v, int max) {
25 return (v > max) ? max : v;
28 //------------------------------------------------------------------------------
29 // Compute susceptibility based on DCT-coeff histograms:
30 // the higher, the "easier" the macroblock is to compress.
32 const int VP8DspScan[16 + 4 + 4] = {
33 // Luma
34 0 + 0 * BPS, 4 + 0 * BPS, 8 + 0 * BPS, 12 + 0 * BPS,
35 0 + 4 * BPS, 4 + 4 * BPS, 8 + 4 * BPS, 12 + 4 * BPS,
36 0 + 8 * BPS, 4 + 8 * BPS, 8 + 8 * BPS, 12 + 8 * BPS,
37 0 + 12 * BPS, 4 + 12 * BPS, 8 + 12 * BPS, 12 + 12 * BPS,
39 0 + 0 * BPS, 4 + 0 * BPS, 0 + 4 * BPS, 4 + 4 * BPS, // U
40 8 + 0 * BPS, 12 + 0 * BPS, 8 + 4 * BPS, 12 + 4 * BPS // V
43 static void CollectHistogram(const uint8_t* ref, const uint8_t* pred,
44 int start_block, int end_block,
45 VP8Histogram* const histo) {
46 int j;
47 for (j = start_block; j < end_block; ++j) {
48 int k;
49 int16_t out[16];
51 VP8FTransform(ref + VP8DspScan[j], pred + VP8DspScan[j], out);
53 // Convert coefficients to bin.
54 for (k = 0; k < 16; ++k) {
55 const int v = abs(out[k]) >> 3; // TODO(skal): add rounding?
56 const int clipped_value = clip_max(v, MAX_COEFF_THRESH);
57 histo->distribution[clipped_value]++;
62 //------------------------------------------------------------------------------
63 // run-time tables (~4k)
65 static uint8_t clip1[255 + 510 + 1]; // clips [-255,510] to [0,255]
67 // We declare this variable 'volatile' to prevent instruction reordering
68 // and make sure it's set to true _last_ (so as to be thread-safe)
69 static volatile int tables_ok = 0;
71 static void InitTables(void) {
72 if (!tables_ok) {
73 int i;
74 for (i = -255; i <= 255 + 255; ++i) {
75 clip1[255 + i] = clip_8b(i);
77 tables_ok = 1;
82 //------------------------------------------------------------------------------
83 // Transforms (Paragraph 14.4)
85 #define STORE(x, y, v) \
86 dst[(x) + (y) * BPS] = clip_8b(ref[(x) + (y) * BPS] + ((v) >> 3))
88 static const int kC1 = 20091 + (1 << 16);
89 static const int kC2 = 35468;
90 #define MUL(a, b) (((a) * (b)) >> 16)
92 static WEBP_INLINE void ITransformOne(const uint8_t* ref, const int16_t* in,
93 uint8_t* dst) {
94 int C[4 * 4], *tmp;
95 int i;
96 tmp = C;
97 for (i = 0; i < 4; ++i) { // vertical pass
98 const int a = in[0] + in[8];
99 const int b = in[0] - in[8];
100 const int c = MUL(in[4], kC2) - MUL(in[12], kC1);
101 const int d = MUL(in[4], kC1) + MUL(in[12], kC2);
102 tmp[0] = a + d;
103 tmp[1] = b + c;
104 tmp[2] = b - c;
105 tmp[3] = a - d;
106 tmp += 4;
107 in++;
110 tmp = C;
111 for (i = 0; i < 4; ++i) { // horizontal pass
112 const int dc = tmp[0] + 4;
113 const int a = dc + tmp[8];
114 const int b = dc - tmp[8];
115 const int c = MUL(tmp[4], kC2) - MUL(tmp[12], kC1);
116 const int d = MUL(tmp[4], kC1) + MUL(tmp[12], kC2);
117 STORE(0, i, a + d);
118 STORE(1, i, b + c);
119 STORE(2, i, b - c);
120 STORE(3, i, a - d);
121 tmp++;
125 static void ITransform(const uint8_t* ref, const int16_t* in, uint8_t* dst,
126 int do_two) {
127 ITransformOne(ref, in, dst);
128 if (do_two) {
129 ITransformOne(ref + 4, in + 16, dst + 4);
133 static void FTransform(const uint8_t* src, const uint8_t* ref, int16_t* out) {
134 int i;
135 int tmp[16];
136 for (i = 0; i < 4; ++i, src += BPS, ref += BPS) {
137 const int d0 = src[0] - ref[0]; // 9bit dynamic range ([-255,255])
138 const int d1 = src[1] - ref[1];
139 const int d2 = src[2] - ref[2];
140 const int d3 = src[3] - ref[3];
141 const int a0 = (d0 + d3); // 10b [-510,510]
142 const int a1 = (d1 + d2);
143 const int a2 = (d1 - d2);
144 const int a3 = (d0 - d3);
145 tmp[0 + i * 4] = (a0 + a1) * 8; // 14b [-8160,8160]
146 tmp[1 + i * 4] = (a2 * 2217 + a3 * 5352 + 1812) >> 9; // [-7536,7542]
147 tmp[2 + i * 4] = (a0 - a1) * 8;
148 tmp[3 + i * 4] = (a3 * 2217 - a2 * 5352 + 937) >> 9;
150 for (i = 0; i < 4; ++i) {
151 const int a0 = (tmp[0 + i] + tmp[12 + i]); // 15b
152 const int a1 = (tmp[4 + i] + tmp[ 8 + i]);
153 const int a2 = (tmp[4 + i] - tmp[ 8 + i]);
154 const int a3 = (tmp[0 + i] - tmp[12 + i]);
155 out[0 + i] = (a0 + a1 + 7) >> 4; // 12b
156 out[4 + i] = ((a2 * 2217 + a3 * 5352 + 12000) >> 16) + (a3 != 0);
157 out[8 + i] = (a0 - a1 + 7) >> 4;
158 out[12+ i] = ((a3 * 2217 - a2 * 5352 + 51000) >> 16);
162 static void FTransformWHT(const int16_t* in, int16_t* out) {
163 // input is 12b signed
164 int32_t tmp[16];
165 int i;
166 for (i = 0; i < 4; ++i, in += 64) {
167 const int a0 = (in[0 * 16] + in[2 * 16]); // 13b
168 const int a1 = (in[1 * 16] + in[3 * 16]);
169 const int a2 = (in[1 * 16] - in[3 * 16]);
170 const int a3 = (in[0 * 16] - in[2 * 16]);
171 tmp[0 + i * 4] = a0 + a1; // 14b
172 tmp[1 + i * 4] = a3 + a2;
173 tmp[2 + i * 4] = a3 - a2;
174 tmp[3 + i * 4] = a0 - a1;
176 for (i = 0; i < 4; ++i) {
177 const int a0 = (tmp[0 + i] + tmp[8 + i]); // 15b
178 const int a1 = (tmp[4 + i] + tmp[12+ i]);
179 const int a2 = (tmp[4 + i] - tmp[12+ i]);
180 const int a3 = (tmp[0 + i] - tmp[8 + i]);
181 const int b0 = a0 + a1; // 16b
182 const int b1 = a3 + a2;
183 const int b2 = a3 - a2;
184 const int b3 = a0 - a1;
185 out[ 0 + i] = b0 >> 1; // 15b
186 out[ 4 + i] = b1 >> 1;
187 out[ 8 + i] = b2 >> 1;
188 out[12 + i] = b3 >> 1;
192 #undef MUL
193 #undef STORE
195 //------------------------------------------------------------------------------
196 // Intra predictions
198 #define DST(x, y) dst[(x) + (y) * BPS]
200 static WEBP_INLINE void Fill(uint8_t* dst, int value, int size) {
201 int j;
202 for (j = 0; j < size; ++j) {
203 memset(dst + j * BPS, value, size);
207 static WEBP_INLINE void VerticalPred(uint8_t* dst,
208 const uint8_t* top, int size) {
209 int j;
210 if (top) {
211 for (j = 0; j < size; ++j) memcpy(dst + j * BPS, top, size);
212 } else {
213 Fill(dst, 127, size);
217 static WEBP_INLINE void HorizontalPred(uint8_t* dst,
218 const uint8_t* left, int size) {
219 if (left) {
220 int j;
221 for (j = 0; j < size; ++j) {
222 memset(dst + j * BPS, left[j], size);
224 } else {
225 Fill(dst, 129, size);
229 static WEBP_INLINE void TrueMotion(uint8_t* dst, const uint8_t* left,
230 const uint8_t* top, int size) {
231 int y;
232 if (left) {
233 if (top) {
234 const uint8_t* const clip = clip1 + 255 - left[-1];
235 for (y = 0; y < size; ++y) {
236 const uint8_t* const clip_table = clip + left[y];
237 int x;
238 for (x = 0; x < size; ++x) {
239 dst[x] = clip_table[top[x]];
241 dst += BPS;
243 } else {
244 HorizontalPred(dst, left, size);
246 } else {
247 // true motion without left samples (hence: with default 129 value)
248 // is equivalent to VE prediction where you just copy the top samples.
249 // Note that if top samples are not available, the default value is
250 // then 129, and not 127 as in the VerticalPred case.
251 if (top) {
252 VerticalPred(dst, top, size);
253 } else {
254 Fill(dst, 129, size);
259 static WEBP_INLINE void DCMode(uint8_t* dst, const uint8_t* left,
260 const uint8_t* top,
261 int size, int round, int shift) {
262 int DC = 0;
263 int j;
264 if (top) {
265 for (j = 0; j < size; ++j) DC += top[j];
266 if (left) { // top and left present
267 for (j = 0; j < size; ++j) DC += left[j];
268 } else { // top, but no left
269 DC += DC;
271 DC = (DC + round) >> shift;
272 } else if (left) { // left but no top
273 for (j = 0; j < size; ++j) DC += left[j];
274 DC += DC;
275 DC = (DC + round) >> shift;
276 } else { // no top, no left, nothing.
277 DC = 0x80;
279 Fill(dst, DC, size);
282 //------------------------------------------------------------------------------
283 // Chroma 8x8 prediction (paragraph 12.2)
285 static void IntraChromaPreds(uint8_t* dst, const uint8_t* left,
286 const uint8_t* top) {
287 // U block
288 DCMode(C8DC8 + dst, left, top, 8, 8, 4);
289 VerticalPred(C8VE8 + dst, top, 8);
290 HorizontalPred(C8HE8 + dst, left, 8);
291 TrueMotion(C8TM8 + dst, left, top, 8);
292 // V block
293 dst += 8;
294 if (top) top += 8;
295 if (left) left += 16;
296 DCMode(C8DC8 + dst, left, top, 8, 8, 4);
297 VerticalPred(C8VE8 + dst, top, 8);
298 HorizontalPred(C8HE8 + dst, left, 8);
299 TrueMotion(C8TM8 + dst, left, top, 8);
302 //------------------------------------------------------------------------------
303 // luma 16x16 prediction (paragraph 12.3)
305 static void Intra16Preds(uint8_t* dst,
306 const uint8_t* left, const uint8_t* top) {
307 DCMode(I16DC16 + dst, left, top, 16, 16, 5);
308 VerticalPred(I16VE16 + dst, top, 16);
309 HorizontalPred(I16HE16 + dst, left, 16);
310 TrueMotion(I16TM16 + dst, left, top, 16);
313 //------------------------------------------------------------------------------
314 // luma 4x4 prediction
316 #define AVG3(a, b, c) (((a) + 2 * (b) + (c) + 2) >> 2)
317 #define AVG2(a, b) (((a) + (b) + 1) >> 1)
319 static void VE4(uint8_t* dst, const uint8_t* top) { // vertical
320 const uint8_t vals[4] = {
321 AVG3(top[-1], top[0], top[1]),
322 AVG3(top[ 0], top[1], top[2]),
323 AVG3(top[ 1], top[2], top[3]),
324 AVG3(top[ 2], top[3], top[4])
326 int i;
327 for (i = 0; i < 4; ++i) {
328 memcpy(dst + i * BPS, vals, 4);
332 static void HE4(uint8_t* dst, const uint8_t* top) { // horizontal
333 const int X = top[-1];
334 const int I = top[-2];
335 const int J = top[-3];
336 const int K = top[-4];
337 const int L = top[-5];
338 *(uint32_t*)(dst + 0 * BPS) = 0x01010101U * AVG3(X, I, J);
339 *(uint32_t*)(dst + 1 * BPS) = 0x01010101U * AVG3(I, J, K);
340 *(uint32_t*)(dst + 2 * BPS) = 0x01010101U * AVG3(J, K, L);
341 *(uint32_t*)(dst + 3 * BPS) = 0x01010101U * AVG3(K, L, L);
344 static void DC4(uint8_t* dst, const uint8_t* top) {
345 uint32_t dc = 4;
346 int i;
347 for (i = 0; i < 4; ++i) dc += top[i] + top[-5 + i];
348 Fill(dst, dc >> 3, 4);
351 static void RD4(uint8_t* dst, const uint8_t* top) {
352 const int X = top[-1];
353 const int I = top[-2];
354 const int J = top[-3];
355 const int K = top[-4];
356 const int L = top[-5];
357 const int A = top[0];
358 const int B = top[1];
359 const int C = top[2];
360 const int D = top[3];
361 DST(0, 3) = AVG3(J, K, L);
362 DST(0, 2) = DST(1, 3) = AVG3(I, J, K);
363 DST(0, 1) = DST(1, 2) = DST(2, 3) = AVG3(X, I, J);
364 DST(0, 0) = DST(1, 1) = DST(2, 2) = DST(3, 3) = AVG3(A, X, I);
365 DST(1, 0) = DST(2, 1) = DST(3, 2) = AVG3(B, A, X);
366 DST(2, 0) = DST(3, 1) = AVG3(C, B, A);
367 DST(3, 0) = AVG3(D, C, B);
370 static void LD4(uint8_t* dst, const uint8_t* top) {
371 const int A = top[0];
372 const int B = top[1];
373 const int C = top[2];
374 const int D = top[3];
375 const int E = top[4];
376 const int F = top[5];
377 const int G = top[6];
378 const int H = top[7];
379 DST(0, 0) = AVG3(A, B, C);
380 DST(1, 0) = DST(0, 1) = AVG3(B, C, D);
381 DST(2, 0) = DST(1, 1) = DST(0, 2) = AVG3(C, D, E);
382 DST(3, 0) = DST(2, 1) = DST(1, 2) = DST(0, 3) = AVG3(D, E, F);
383 DST(3, 1) = DST(2, 2) = DST(1, 3) = AVG3(E, F, G);
384 DST(3, 2) = DST(2, 3) = AVG3(F, G, H);
385 DST(3, 3) = AVG3(G, H, H);
388 static void VR4(uint8_t* dst, const uint8_t* top) {
389 const int X = top[-1];
390 const int I = top[-2];
391 const int J = top[-3];
392 const int K = top[-4];
393 const int A = top[0];
394 const int B = top[1];
395 const int C = top[2];
396 const int D = top[3];
397 DST(0, 0) = DST(1, 2) = AVG2(X, A);
398 DST(1, 0) = DST(2, 2) = AVG2(A, B);
399 DST(2, 0) = DST(3, 2) = AVG2(B, C);
400 DST(3, 0) = AVG2(C, D);
402 DST(0, 3) = AVG3(K, J, I);
403 DST(0, 2) = AVG3(J, I, X);
404 DST(0, 1) = DST(1, 3) = AVG3(I, X, A);
405 DST(1, 1) = DST(2, 3) = AVG3(X, A, B);
406 DST(2, 1) = DST(3, 3) = AVG3(A, B, C);
407 DST(3, 1) = AVG3(B, C, D);
410 static void VL4(uint8_t* dst, const uint8_t* top) {
411 const int A = top[0];
412 const int B = top[1];
413 const int C = top[2];
414 const int D = top[3];
415 const int E = top[4];
416 const int F = top[5];
417 const int G = top[6];
418 const int H = top[7];
419 DST(0, 0) = AVG2(A, B);
420 DST(1, 0) = DST(0, 2) = AVG2(B, C);
421 DST(2, 0) = DST(1, 2) = AVG2(C, D);
422 DST(3, 0) = DST(2, 2) = AVG2(D, E);
424 DST(0, 1) = AVG3(A, B, C);
425 DST(1, 1) = DST(0, 3) = AVG3(B, C, D);
426 DST(2, 1) = DST(1, 3) = AVG3(C, D, E);
427 DST(3, 1) = DST(2, 3) = AVG3(D, E, F);
428 DST(3, 2) = AVG3(E, F, G);
429 DST(3, 3) = AVG3(F, G, H);
432 static void HU4(uint8_t* dst, const uint8_t* top) {
433 const int I = top[-2];
434 const int J = top[-3];
435 const int K = top[-4];
436 const int L = top[-5];
437 DST(0, 0) = AVG2(I, J);
438 DST(2, 0) = DST(0, 1) = AVG2(J, K);
439 DST(2, 1) = DST(0, 2) = AVG2(K, L);
440 DST(1, 0) = AVG3(I, J, K);
441 DST(3, 0) = DST(1, 1) = AVG3(J, K, L);
442 DST(3, 1) = DST(1, 2) = AVG3(K, L, L);
443 DST(3, 2) = DST(2, 2) =
444 DST(0, 3) = DST(1, 3) = DST(2, 3) = DST(3, 3) = L;
447 static void HD4(uint8_t* dst, const uint8_t* top) {
448 const int X = top[-1];
449 const int I = top[-2];
450 const int J = top[-3];
451 const int K = top[-4];
452 const int L = top[-5];
453 const int A = top[0];
454 const int B = top[1];
455 const int C = top[2];
457 DST(0, 0) = DST(2, 1) = AVG2(I, X);
458 DST(0, 1) = DST(2, 2) = AVG2(J, I);
459 DST(0, 2) = DST(2, 3) = AVG2(K, J);
460 DST(0, 3) = AVG2(L, K);
462 DST(3, 0) = AVG3(A, B, C);
463 DST(2, 0) = AVG3(X, A, B);
464 DST(1, 0) = DST(3, 1) = AVG3(I, X, A);
465 DST(1, 1) = DST(3, 2) = AVG3(J, I, X);
466 DST(1, 2) = DST(3, 3) = AVG3(K, J, I);
467 DST(1, 3) = AVG3(L, K, J);
470 static void TM4(uint8_t* dst, const uint8_t* top) {
471 int x, y;
472 const uint8_t* const clip = clip1 + 255 - top[-1];
473 for (y = 0; y < 4; ++y) {
474 const uint8_t* const clip_table = clip + top[-2 - y];
475 for (x = 0; x < 4; ++x) {
476 dst[x] = clip_table[top[x]];
478 dst += BPS;
482 #undef DST
483 #undef AVG3
484 #undef AVG2
486 // Left samples are top[-5 .. -2], top_left is top[-1], top are
487 // located at top[0..3], and top right is top[4..7]
488 static void Intra4Preds(uint8_t* dst, const uint8_t* top) {
489 DC4(I4DC4 + dst, top);
490 TM4(I4TM4 + dst, top);
491 VE4(I4VE4 + dst, top);
492 HE4(I4HE4 + dst, top);
493 RD4(I4RD4 + dst, top);
494 VR4(I4VR4 + dst, top);
495 LD4(I4LD4 + dst, top);
496 VL4(I4VL4 + dst, top);
497 HD4(I4HD4 + dst, top);
498 HU4(I4HU4 + dst, top);
501 //------------------------------------------------------------------------------
502 // Metric
504 static WEBP_INLINE int GetSSE(const uint8_t* a, const uint8_t* b,
505 int w, int h) {
506 int count = 0;
507 int y, x;
508 for (y = 0; y < h; ++y) {
509 for (x = 0; x < w; ++x) {
510 const int diff = (int)a[x] - b[x];
511 count += diff * diff;
513 a += BPS;
514 b += BPS;
516 return count;
519 static int SSE16x16(const uint8_t* a, const uint8_t* b) {
520 return GetSSE(a, b, 16, 16);
522 static int SSE16x8(const uint8_t* a, const uint8_t* b) {
523 return GetSSE(a, b, 16, 8);
525 static int SSE8x8(const uint8_t* a, const uint8_t* b) {
526 return GetSSE(a, b, 8, 8);
528 static int SSE4x4(const uint8_t* a, const uint8_t* b) {
529 return GetSSE(a, b, 4, 4);
532 //------------------------------------------------------------------------------
533 // Texture distortion
535 // We try to match the spectral content (weighted) between source and
536 // reconstructed samples.
538 // Hadamard transform
539 // Returns the weighted sum of the absolute value of transformed coefficients.
540 static int TTransform(const uint8_t* in, const uint16_t* w) {
541 int sum = 0;
542 int tmp[16];
543 int i;
544 // horizontal pass
545 for (i = 0; i < 4; ++i, in += BPS) {
546 const int a0 = in[0] + in[2];
547 const int a1 = in[1] + in[3];
548 const int a2 = in[1] - in[3];
549 const int a3 = in[0] - in[2];
550 tmp[0 + i * 4] = a0 + a1;
551 tmp[1 + i * 4] = a3 + a2;
552 tmp[2 + i * 4] = a3 - a2;
553 tmp[3 + i * 4] = a0 - a1;
555 // vertical pass
556 for (i = 0; i < 4; ++i, ++w) {
557 const int a0 = tmp[0 + i] + tmp[8 + i];
558 const int a1 = tmp[4 + i] + tmp[12+ i];
559 const int a2 = tmp[4 + i] - tmp[12+ i];
560 const int a3 = tmp[0 + i] - tmp[8 + i];
561 const int b0 = a0 + a1;
562 const int b1 = a3 + a2;
563 const int b2 = a3 - a2;
564 const int b3 = a0 - a1;
566 sum += w[ 0] * abs(b0);
567 sum += w[ 4] * abs(b1);
568 sum += w[ 8] * abs(b2);
569 sum += w[12] * abs(b3);
571 return sum;
574 static int Disto4x4(const uint8_t* const a, const uint8_t* const b,
575 const uint16_t* const w) {
576 const int sum1 = TTransform(a, w);
577 const int sum2 = TTransform(b, w);
578 return abs(sum2 - sum1) >> 5;
581 static int Disto16x16(const uint8_t* const a, const uint8_t* const b,
582 const uint16_t* const w) {
583 int D = 0;
584 int x, y;
585 for (y = 0; y < 16 * BPS; y += 4 * BPS) {
586 for (x = 0; x < 16; x += 4) {
587 D += Disto4x4(a + x + y, b + x + y, w);
590 return D;
593 //------------------------------------------------------------------------------
594 // Quantization
597 static const uint8_t kZigzag[16] = {
598 0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15
601 // Simple quantization
602 static int QuantizeBlock(int16_t in[16], int16_t out[16],
603 const VP8Matrix* const mtx) {
604 int last = -1;
605 int n;
606 for (n = 0; n < 16; ++n) {
607 const int j = kZigzag[n];
608 const int sign = (in[j] < 0);
609 const uint32_t coeff = (sign ? -in[j] : in[j]) + mtx->sharpen_[j];
610 if (coeff > mtx->zthresh_[j]) {
611 const uint32_t Q = mtx->q_[j];
612 const uint32_t iQ = mtx->iq_[j];
613 const uint32_t B = mtx->bias_[j];
614 int level = QUANTDIV(coeff, iQ, B);
615 if (level > MAX_LEVEL) level = MAX_LEVEL;
616 if (sign) level = -level;
617 in[j] = level * Q;
618 out[n] = level;
619 if (level) last = n;
620 } else {
621 out[n] = 0;
622 in[j] = 0;
625 return (last >= 0);
628 static int QuantizeBlockWHT(int16_t in[16], int16_t out[16],
629 const VP8Matrix* const mtx) {
630 int n, last = -1;
631 for (n = 0; n < 16; ++n) {
632 const int j = kZigzag[n];
633 const int sign = (in[j] < 0);
634 const uint32_t coeff = sign ? -in[j] : in[j];
635 assert(mtx->sharpen_[j] == 0);
636 if (coeff > mtx->zthresh_[j]) {
637 const uint32_t Q = mtx->q_[j];
638 const uint32_t iQ = mtx->iq_[j];
639 const uint32_t B = mtx->bias_[j];
640 int level = QUANTDIV(coeff, iQ, B);
641 if (level > MAX_LEVEL) level = MAX_LEVEL;
642 if (sign) level = -level;
643 in[j] = level * Q;
644 out[n] = level;
645 if (level) last = n;
646 } else {
647 out[n] = 0;
648 in[j] = 0;
651 return (last >= 0);
654 //------------------------------------------------------------------------------
655 // Block copy
657 static WEBP_INLINE void Copy(const uint8_t* src, uint8_t* dst, int size) {
658 int y;
659 for (y = 0; y < size; ++y) {
660 memcpy(dst, src, size);
661 src += BPS;
662 dst += BPS;
666 static void Copy4x4(const uint8_t* src, uint8_t* dst) { Copy(src, dst, 4); }
668 //------------------------------------------------------------------------------
669 // Initialization
671 // Speed-critical function pointers. We have to initialize them to the default
672 // implementations within VP8EncDspInit().
673 VP8CHisto VP8CollectHistogram;
674 VP8Idct VP8ITransform;
675 VP8Fdct VP8FTransform;
676 VP8WHT VP8FTransformWHT;
677 VP8Intra4Preds VP8EncPredLuma4;
678 VP8IntraPreds VP8EncPredLuma16;
679 VP8IntraPreds VP8EncPredChroma8;
680 VP8Metric VP8SSE16x16;
681 VP8Metric VP8SSE8x8;
682 VP8Metric VP8SSE16x8;
683 VP8Metric VP8SSE4x4;
684 VP8WMetric VP8TDisto4x4;
685 VP8WMetric VP8TDisto16x16;
686 VP8QuantizeBlock VP8EncQuantizeBlock;
687 VP8QuantizeBlockWHT VP8EncQuantizeBlockWHT;
688 VP8BlockCopy VP8Copy4x4;
690 extern void VP8EncDspInitSSE2(void);
691 extern void VP8EncDspInitAVX2(void);
692 extern void VP8EncDspInitNEON(void);
693 extern void VP8EncDspInitMIPS32(void);
695 static volatile VP8CPUInfo enc_last_cpuinfo_used =
696 (VP8CPUInfo)&enc_last_cpuinfo_used;
698 void VP8EncDspInit(void) {
699 if (enc_last_cpuinfo_used == VP8GetCPUInfo) return;
701 VP8DspInit(); // common inverse transforms
702 InitTables();
704 // default C implementations
705 VP8CollectHistogram = CollectHistogram;
706 VP8ITransform = ITransform;
707 VP8FTransform = FTransform;
708 VP8FTransformWHT = FTransformWHT;
709 VP8EncPredLuma4 = Intra4Preds;
710 VP8EncPredLuma16 = Intra16Preds;
711 VP8EncPredChroma8 = IntraChromaPreds;
712 VP8SSE16x16 = SSE16x16;
713 VP8SSE8x8 = SSE8x8;
714 VP8SSE16x8 = SSE16x8;
715 VP8SSE4x4 = SSE4x4;
716 VP8TDisto4x4 = Disto4x4;
717 VP8TDisto16x16 = Disto16x16;
718 VP8EncQuantizeBlock = QuantizeBlock;
719 VP8EncQuantizeBlockWHT = QuantizeBlockWHT;
720 VP8Copy4x4 = Copy4x4;
722 // If defined, use CPUInfo() to overwrite some pointers with faster versions.
723 if (VP8GetCPUInfo != NULL) {
724 #if defined(WEBP_USE_SSE2)
725 if (VP8GetCPUInfo(kSSE2)) {
726 VP8EncDspInitSSE2();
728 #endif
729 #if defined(WEBP_USE_AVX2)
730 if (VP8GetCPUInfo(kAVX2)) {
731 VP8EncDspInitAVX2();
733 #endif
734 #if defined(WEBP_USE_NEON)
735 if (VP8GetCPUInfo(kNEON)) {
736 VP8EncDspInitNEON();
738 #endif
739 #if defined(WEBP_USE_MIPS32)
740 if (VP8GetCPUInfo(kMIPS32)) {
741 VP8EncDspInitMIPS32();
743 #endif
745 enc_last_cpuinfo_used = VP8GetCPUInfo;