1 // Copyright 2010 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 decoding functions.
11 //
12 // Author: Skal (pascal.massimino@gmail.com)
13
14 #include "./dsp.h"
15 #include "../dec/vp8i.h"
16
17 //------------------------------------------------------------------------------
18
clip_8b(int v)19 static WEBP_INLINE uint8_t clip_8b(int v) {
20 return (!(v & ~0xff)) ? v : (v < 0) ? 0 : 255;
21 }
22
23 //------------------------------------------------------------------------------
24 // Transforms (Paragraph 14.4)
25
26 #define STORE(x, y, v) \
27 dst[x + y * BPS] = clip_8b(dst[x + y * BPS] + ((v) >> 3))
28
29 #define STORE2(y, dc, d, c) do { \
30 const int DC = (dc); \
31 STORE(0, y, DC + (d)); \
32 STORE(1, y, DC + (c)); \
33 STORE(2, y, DC - (c)); \
34 STORE(3, y, DC - (d)); \
35 } while (0)
36
37 static const int kC1 = 20091 + (1 << 16);
38 static const int kC2 = 35468;
39 #define MUL(a, b) (((a) * (b)) >> 16)
40
TransformOne(const int16_t * in,uint8_t * dst)41 static void TransformOne(const int16_t* in, uint8_t* dst) {
42 int C[4 * 4], *tmp;
43 int i;
44 tmp = C;
45 for (i = 0; i < 4; ++i) { // vertical pass
46 const int a = in[0] + in[8]; // [-4096, 4094]
47 const int b = in[0] - in[8]; // [-4095, 4095]
48 const int c = MUL(in[4], kC2) - MUL(in[12], kC1); // [-3783, 3783]
49 const int d = MUL(in[4], kC1) + MUL(in[12], kC2); // [-3785, 3781]
50 tmp[0] = a + d; // [-7881, 7875]
51 tmp[1] = b + c; // [-7878, 7878]
52 tmp[2] = b - c; // [-7878, 7878]
53 tmp[3] = a - d; // [-7877, 7879]
54 tmp += 4;
55 in++;
56 }
57 // Each pass is expanding the dynamic range by ~3.85 (upper bound).
58 // The exact value is (2. + (kC1 + kC2) / 65536).
59 // After the second pass, maximum interval is [-3794, 3794], assuming
60 // an input in [-2048, 2047] interval. We then need to add a dst value
61 // in the [0, 255] range.
62 // In the worst case scenario, the input to clip_8b() can be as large as
63 // [-60713, 60968].
64 tmp = C;
65 for (i = 0; i < 4; ++i) { // horizontal pass
66 const int dc = tmp[0] + 4;
67 const int a = dc + tmp[8];
68 const int b = dc - tmp[8];
69 const int c = MUL(tmp[4], kC2) - MUL(tmp[12], kC1);
70 const int d = MUL(tmp[4], kC1) + MUL(tmp[12], kC2);
71 STORE(0, 0, a + d);
72 STORE(1, 0, b + c);
73 STORE(2, 0, b - c);
74 STORE(3, 0, a - d);
75 tmp++;
76 dst += BPS;
77 }
78 }
79
80 // Simplified transform when only in[0], in[1] and in[4] are non-zero
TransformAC3(const int16_t * in,uint8_t * dst)81 static void TransformAC3(const int16_t* in, uint8_t* dst) {
82 const int a = in[0] + 4;
83 const int c4 = MUL(in[4], kC2);
84 const int d4 = MUL(in[4], kC1);
85 const int c1 = MUL(in[1], kC2);
86 const int d1 = MUL(in[1], kC1);
87 STORE2(0, a + d4, d1, c1);
88 STORE2(1, a + c4, d1, c1);
89 STORE2(2, a - c4, d1, c1);
90 STORE2(3, a - d4, d1, c1);
91 }
92 #undef MUL
93 #undef STORE2
94
TransformTwo(const int16_t * in,uint8_t * dst,int do_two)95 static void TransformTwo(const int16_t* in, uint8_t* dst, int do_two) {
96 TransformOne(in, dst);
97 if (do_two) {
98 TransformOne(in + 16, dst + 4);
99 }
100 }
101
TransformUV(const int16_t * in,uint8_t * dst)102 static void TransformUV(const int16_t* in, uint8_t* dst) {
103 VP8Transform(in + 0 * 16, dst, 1);
104 VP8Transform(in + 2 * 16, dst + 4 * BPS, 1);
105 }
106
TransformDC(const int16_t * in,uint8_t * dst)107 static void TransformDC(const int16_t *in, uint8_t* dst) {
108 const int DC = in[0] + 4;
109 int i, j;
110 for (j = 0; j < 4; ++j) {
111 for (i = 0; i < 4; ++i) {
112 STORE(i, j, DC);
113 }
114 }
115 }
116
TransformDCUV(const int16_t * in,uint8_t * dst)117 static void TransformDCUV(const int16_t* in, uint8_t* dst) {
118 if (in[0 * 16]) VP8TransformDC(in + 0 * 16, dst);
119 if (in[1 * 16]) VP8TransformDC(in + 1 * 16, dst + 4);
120 if (in[2 * 16]) VP8TransformDC(in + 2 * 16, dst + 4 * BPS);
121 if (in[3 * 16]) VP8TransformDC(in + 3 * 16, dst + 4 * BPS + 4);
122 }
123
124 #undef STORE
125
126 //------------------------------------------------------------------------------
127 // Paragraph 14.3
128
TransformWHT(const int16_t * in,int16_t * out)129 static void TransformWHT(const int16_t* in, int16_t* out) {
130 int tmp[16];
131 int i;
132 for (i = 0; i < 4; ++i) {
133 const int a0 = in[0 + i] + in[12 + i];
134 const int a1 = in[4 + i] + in[ 8 + i];
135 const int a2 = in[4 + i] - in[ 8 + i];
136 const int a3 = in[0 + i] - in[12 + i];
137 tmp[0 + i] = a0 + a1;
138 tmp[8 + i] = a0 - a1;
139 tmp[4 + i] = a3 + a2;
140 tmp[12 + i] = a3 - a2;
141 }
142 for (i = 0; i < 4; ++i) {
143 const int dc = tmp[0 + i * 4] + 3; // w/ rounder
144 const int a0 = dc + tmp[3 + i * 4];
145 const int a1 = tmp[1 + i * 4] + tmp[2 + i * 4];
146 const int a2 = tmp[1 + i * 4] - tmp[2 + i * 4];
147 const int a3 = dc - tmp[3 + i * 4];
148 out[ 0] = (a0 + a1) >> 3;
149 out[16] = (a3 + a2) >> 3;
150 out[32] = (a0 - a1) >> 3;
151 out[48] = (a3 - a2) >> 3;
152 out += 64;
153 }
154 }
155
156 void (*VP8TransformWHT)(const int16_t* in, int16_t* out);
157
158 //------------------------------------------------------------------------------
159 // Intra predictions
160
161 #define DST(x, y) dst[(x) + (y) * BPS]
162
TrueMotion(uint8_t * dst,int size)163 static WEBP_INLINE void TrueMotion(uint8_t *dst, int size) {
164 const uint8_t* top = dst - BPS;
165 const uint8_t* const clip0 = VP8kclip1 - top[-1];
166 int y;
167 for (y = 0; y < size; ++y) {
168 const uint8_t* const clip = clip0 + dst[-1];
169 int x;
170 for (x = 0; x < size; ++x) {
171 dst[x] = clip[top[x]];
172 }
173 dst += BPS;
174 }
175 }
TM4(uint8_t * dst)176 static void TM4(uint8_t *dst) { TrueMotion(dst, 4); }
TM8uv(uint8_t * dst)177 static void TM8uv(uint8_t *dst) { TrueMotion(dst, 8); }
TM16(uint8_t * dst)178 static void TM16(uint8_t *dst) { TrueMotion(dst, 16); }
179
180 //------------------------------------------------------------------------------
181 // 16x16
182
VE16(uint8_t * dst)183 static void VE16(uint8_t *dst) { // vertical
184 int j;
185 for (j = 0; j < 16; ++j) {
186 memcpy(dst + j * BPS, dst - BPS, 16);
187 }
188 }
189
HE16(uint8_t * dst)190 static void HE16(uint8_t *dst) { // horizontal
191 int j;
192 for (j = 16; j > 0; --j) {
193 memset(dst, dst[-1], 16);
194 dst += BPS;
195 }
196 }
197
Put16(int v,uint8_t * dst)198 static WEBP_INLINE void Put16(int v, uint8_t* dst) {
199 int j;
200 for (j = 0; j < 16; ++j) {
201 memset(dst + j * BPS, v, 16);
202 }
203 }
204
DC16(uint8_t * dst)205 static void DC16(uint8_t *dst) { // DC
206 int DC = 16;
207 int j;
208 for (j = 0; j < 16; ++j) {
209 DC += dst[-1 + j * BPS] + dst[j - BPS];
210 }
211 Put16(DC >> 5, dst);
212 }
213
DC16NoTop(uint8_t * dst)214 static void DC16NoTop(uint8_t *dst) { // DC with top samples not available
215 int DC = 8;
216 int j;
217 for (j = 0; j < 16; ++j) {
218 DC += dst[-1 + j * BPS];
219 }
220 Put16(DC >> 4, dst);
221 }
222
DC16NoLeft(uint8_t * dst)223 static void DC16NoLeft(uint8_t *dst) { // DC with left samples not available
224 int DC = 8;
225 int i;
226 for (i = 0; i < 16; ++i) {
227 DC += dst[i - BPS];
228 }
229 Put16(DC >> 4, dst);
230 }
231
DC16NoTopLeft(uint8_t * dst)232 static void DC16NoTopLeft(uint8_t *dst) { // DC with no top and left samples
233 Put16(0x80, dst);
234 }
235
236 //------------------------------------------------------------------------------
237 // 4x4
238
239 #define AVG3(a, b, c) (((a) + 2 * (b) + (c) + 2) >> 2)
240 #define AVG2(a, b) (((a) + (b) + 1) >> 1)
241
VE4(uint8_t * dst)242 static void VE4(uint8_t *dst) { // vertical
243 const uint8_t* top = dst - BPS;
244 const uint8_t vals[4] = {
245 AVG3(top[-1], top[0], top[1]),
246 AVG3(top[ 0], top[1], top[2]),
247 AVG3(top[ 1], top[2], top[3]),
248 AVG3(top[ 2], top[3], top[4])
249 };
250 int i;
251 for (i = 0; i < 4; ++i) {
252 memcpy(dst + i * BPS, vals, sizeof(vals));
253 }
254 }
255
HE4(uint8_t * dst)256 static void HE4(uint8_t *dst) { // horizontal
257 const int A = dst[-1 - BPS];
258 const int B = dst[-1];
259 const int C = dst[-1 + BPS];
260 const int D = dst[-1 + 2 * BPS];
261 const int E = dst[-1 + 3 * BPS];
262 *(uint32_t*)(dst + 0 * BPS) = 0x01010101U * AVG3(A, B, C);
263 *(uint32_t*)(dst + 1 * BPS) = 0x01010101U * AVG3(B, C, D);
264 *(uint32_t*)(dst + 2 * BPS) = 0x01010101U * AVG3(C, D, E);
265 *(uint32_t*)(dst + 3 * BPS) = 0x01010101U * AVG3(D, E, E);
266 }
267
DC4(uint8_t * dst)268 static void DC4(uint8_t *dst) { // DC
269 uint32_t dc = 4;
270 int i;
271 for (i = 0; i < 4; ++i) dc += dst[i - BPS] + dst[-1 + i * BPS];
272 dc >>= 3;
273 for (i = 0; i < 4; ++i) memset(dst + i * BPS, dc, 4);
274 }
275
RD4(uint8_t * dst)276 static void RD4(uint8_t *dst) { // Down-right
277 const int I = dst[-1 + 0 * BPS];
278 const int J = dst[-1 + 1 * BPS];
279 const int K = dst[-1 + 2 * BPS];
280 const int L = dst[-1 + 3 * BPS];
281 const int X = dst[-1 - BPS];
282 const int A = dst[0 - BPS];
283 const int B = dst[1 - BPS];
284 const int C = dst[2 - BPS];
285 const int D = dst[3 - BPS];
286 DST(0, 3) = AVG3(J, K, L);
287 DST(0, 2) = DST(1, 3) = AVG3(I, J, K);
288 DST(0, 1) = DST(1, 2) = DST(2, 3) = AVG3(X, I, J);
289 DST(0, 0) = DST(1, 1) = DST(2, 2) = DST(3, 3) = AVG3(A, X, I);
290 DST(1, 0) = DST(2, 1) = DST(3, 2) = AVG3(B, A, X);
291 DST(2, 0) = DST(3, 1) = AVG3(C, B, A);
292 DST(3, 0) = AVG3(D, C, B);
293 }
294
LD4(uint8_t * dst)295 static void LD4(uint8_t *dst) { // Down-Left
296 const int A = dst[0 - BPS];
297 const int B = dst[1 - BPS];
298 const int C = dst[2 - BPS];
299 const int D = dst[3 - BPS];
300 const int E = dst[4 - BPS];
301 const int F = dst[5 - BPS];
302 const int G = dst[6 - BPS];
303 const int H = dst[7 - BPS];
304 DST(0, 0) = AVG3(A, B, C);
305 DST(1, 0) = DST(0, 1) = AVG3(B, C, D);
306 DST(2, 0) = DST(1, 1) = DST(0, 2) = AVG3(C, D, E);
307 DST(3, 0) = DST(2, 1) = DST(1, 2) = DST(0, 3) = AVG3(D, E, F);
308 DST(3, 1) = DST(2, 2) = DST(1, 3) = AVG3(E, F, G);
309 DST(3, 2) = DST(2, 3) = AVG3(F, G, H);
310 DST(3, 3) = AVG3(G, H, H);
311 }
312
VR4(uint8_t * dst)313 static void VR4(uint8_t *dst) { // Vertical-Right
314 const int I = dst[-1 + 0 * BPS];
315 const int J = dst[-1 + 1 * BPS];
316 const int K = dst[-1 + 2 * BPS];
317 const int X = dst[-1 - BPS];
318 const int A = dst[0 - BPS];
319 const int B = dst[1 - BPS];
320 const int C = dst[2 - BPS];
321 const int D = dst[3 - BPS];
322 DST(0, 0) = DST(1, 2) = AVG2(X, A);
323 DST(1, 0) = DST(2, 2) = AVG2(A, B);
324 DST(2, 0) = DST(3, 2) = AVG2(B, C);
325 DST(3, 0) = AVG2(C, D);
326
327 DST(0, 3) = AVG3(K, J, I);
328 DST(0, 2) = AVG3(J, I, X);
329 DST(0, 1) = DST(1, 3) = AVG3(I, X, A);
330 DST(1, 1) = DST(2, 3) = AVG3(X, A, B);
331 DST(2, 1) = DST(3, 3) = AVG3(A, B, C);
332 DST(3, 1) = AVG3(B, C, D);
333 }
334
VL4(uint8_t * dst)335 static void VL4(uint8_t *dst) { // Vertical-Left
336 const int A = dst[0 - BPS];
337 const int B = dst[1 - BPS];
338 const int C = dst[2 - BPS];
339 const int D = dst[3 - BPS];
340 const int E = dst[4 - BPS];
341 const int F = dst[5 - BPS];
342 const int G = dst[6 - BPS];
343 const int H = dst[7 - BPS];
344 DST(0, 0) = AVG2(A, B);
345 DST(1, 0) = DST(0, 2) = AVG2(B, C);
346 DST(2, 0) = DST(1, 2) = AVG2(C, D);
347 DST(3, 0) = DST(2, 2) = AVG2(D, E);
348
349 DST(0, 1) = AVG3(A, B, C);
350 DST(1, 1) = DST(0, 3) = AVG3(B, C, D);
351 DST(2, 1) = DST(1, 3) = AVG3(C, D, E);
352 DST(3, 1) = DST(2, 3) = AVG3(D, E, F);
353 DST(3, 2) = AVG3(E, F, G);
354 DST(3, 3) = AVG3(F, G, H);
355 }
356
HU4(uint8_t * dst)357 static void HU4(uint8_t *dst) { // Horizontal-Up
358 const int I = dst[-1 + 0 * BPS];
359 const int J = dst[-1 + 1 * BPS];
360 const int K = dst[-1 + 2 * BPS];
361 const int L = dst[-1 + 3 * BPS];
362 DST(0, 0) = AVG2(I, J);
363 DST(2, 0) = DST(0, 1) = AVG2(J, K);
364 DST(2, 1) = DST(0, 2) = AVG2(K, L);
365 DST(1, 0) = AVG3(I, J, K);
366 DST(3, 0) = DST(1, 1) = AVG3(J, K, L);
367 DST(3, 1) = DST(1, 2) = AVG3(K, L, L);
368 DST(3, 2) = DST(2, 2) =
369 DST(0, 3) = DST(1, 3) = DST(2, 3) = DST(3, 3) = L;
370 }
371
HD4(uint8_t * dst)372 static void HD4(uint8_t *dst) { // Horizontal-Down
373 const int I = dst[-1 + 0 * BPS];
374 const int J = dst[-1 + 1 * BPS];
375 const int K = dst[-1 + 2 * BPS];
376 const int L = dst[-1 + 3 * BPS];
377 const int X = dst[-1 - BPS];
378 const int A = dst[0 - BPS];
379 const int B = dst[1 - BPS];
380 const int C = dst[2 - BPS];
381
382 DST(0, 0) = DST(2, 1) = AVG2(I, X);
383 DST(0, 1) = DST(2, 2) = AVG2(J, I);
384 DST(0, 2) = DST(2, 3) = AVG2(K, J);
385 DST(0, 3) = AVG2(L, K);
386
387 DST(3, 0) = AVG3(A, B, C);
388 DST(2, 0) = AVG3(X, A, B);
389 DST(1, 0) = DST(3, 1) = AVG3(I, X, A);
390 DST(1, 1) = DST(3, 2) = AVG3(J, I, X);
391 DST(1, 2) = DST(3, 3) = AVG3(K, J, I);
392 DST(1, 3) = AVG3(L, K, J);
393 }
394
395 #undef DST
396 #undef AVG3
397 #undef AVG2
398
399 //------------------------------------------------------------------------------
400 // Chroma
401
VE8uv(uint8_t * dst)402 static void VE8uv(uint8_t *dst) { // vertical
403 int j;
404 for (j = 0; j < 8; ++j) {
405 memcpy(dst + j * BPS, dst - BPS, 8);
406 }
407 }
408
HE8uv(uint8_t * dst)409 static void HE8uv(uint8_t *dst) { // horizontal
410 int j;
411 for (j = 0; j < 8; ++j) {
412 memset(dst, dst[-1], 8);
413 dst += BPS;
414 }
415 }
416
417 // helper for chroma-DC predictions
Put8x8uv(uint8_t value,uint8_t * dst)418 static WEBP_INLINE void Put8x8uv(uint8_t value, uint8_t* dst) {
419 int j;
420 for (j = 0; j < 8; ++j) {
421 memset(dst + j * BPS, value, 8);
422 }
423 }
424
DC8uv(uint8_t * dst)425 static void DC8uv(uint8_t *dst) { // DC
426 int dc0 = 8;
427 int i;
428 for (i = 0; i < 8; ++i) {
429 dc0 += dst[i - BPS] + dst[-1 + i * BPS];
430 }
431 Put8x8uv(dc0 >> 4, dst);
432 }
433
DC8uvNoLeft(uint8_t * dst)434 static void DC8uvNoLeft(uint8_t *dst) { // DC with no left samples
435 int dc0 = 4;
436 int i;
437 for (i = 0; i < 8; ++i) {
438 dc0 += dst[i - BPS];
439 }
440 Put8x8uv(dc0 >> 3, dst);
441 }
442
DC8uvNoTop(uint8_t * dst)443 static void DC8uvNoTop(uint8_t *dst) { // DC with no top samples
444 int dc0 = 4;
445 int i;
446 for (i = 0; i < 8; ++i) {
447 dc0 += dst[-1 + i * BPS];
448 }
449 Put8x8uv(dc0 >> 3, dst);
450 }
451
DC8uvNoTopLeft(uint8_t * dst)452 static void DC8uvNoTopLeft(uint8_t *dst) { // DC with nothing
453 Put8x8uv(0x80, dst);
454 }
455
456 //------------------------------------------------------------------------------
457 // default C implementations
458
459 const VP8PredFunc VP8PredLuma4[NUM_BMODES] = {
460 DC4, TM4, VE4, HE4, RD4, VR4, LD4, VL4, HD4, HU4
461 };
462
463 const VP8PredFunc VP8PredLuma16[NUM_B_DC_MODES] = {
464 DC16, TM16, VE16, HE16,
465 DC16NoTop, DC16NoLeft, DC16NoTopLeft
466 };
467
468 const VP8PredFunc VP8PredChroma8[NUM_B_DC_MODES] = {
469 DC8uv, TM8uv, VE8uv, HE8uv,
470 DC8uvNoTop, DC8uvNoLeft, DC8uvNoTopLeft
471 };
472
473 //------------------------------------------------------------------------------
474 // Edge filtering functions
475
476 // 4 pixels in, 2 pixels out
do_filter2(uint8_t * p,int step)477 static WEBP_INLINE void do_filter2(uint8_t* p, int step) {
478 const int p1 = p[-2*step], p0 = p[-step], q0 = p[0], q1 = p[step];
479 const int a = 3 * (q0 - p0) + VP8ksclip1[p1 - q1]; // in [-893,892]
480 const int a1 = VP8ksclip2[(a + 4) >> 3]; // in [-16,15]
481 const int a2 = VP8ksclip2[(a + 3) >> 3];
482 p[-step] = VP8kclip1[p0 + a2];
483 p[ 0] = VP8kclip1[q0 - a1];
484 }
485
486 // 4 pixels in, 4 pixels out
do_filter4(uint8_t * p,int step)487 static WEBP_INLINE void do_filter4(uint8_t* p, int step) {
488 const int p1 = p[-2*step], p0 = p[-step], q0 = p[0], q1 = p[step];
489 const int a = 3 * (q0 - p0);
490 const int a1 = VP8ksclip2[(a + 4) >> 3];
491 const int a2 = VP8ksclip2[(a + 3) >> 3];
492 const int a3 = (a1 + 1) >> 1;
493 p[-2*step] = VP8kclip1[p1 + a3];
494 p[- step] = VP8kclip1[p0 + a2];
495 p[ 0] = VP8kclip1[q0 - a1];
496 p[ step] = VP8kclip1[q1 - a3];
497 }
498
499 // 6 pixels in, 6 pixels out
do_filter6(uint8_t * p,int step)500 static WEBP_INLINE void do_filter6(uint8_t* p, int step) {
501 const int p2 = p[-3*step], p1 = p[-2*step], p0 = p[-step];
502 const int q0 = p[0], q1 = p[step], q2 = p[2*step];
503 const int a = VP8ksclip1[3 * (q0 - p0) + VP8ksclip1[p1 - q1]];
504 // a is in [-128,127], a1 in [-27,27], a2 in [-18,18] and a3 in [-9,9]
505 const int a1 = (27 * a + 63) >> 7; // eq. to ((3 * a + 7) * 9) >> 7
506 const int a2 = (18 * a + 63) >> 7; // eq. to ((2 * a + 7) * 9) >> 7
507 const int a3 = (9 * a + 63) >> 7; // eq. to ((1 * a + 7) * 9) >> 7
508 p[-3*step] = VP8kclip1[p2 + a3];
509 p[-2*step] = VP8kclip1[p1 + a2];
510 p[- step] = VP8kclip1[p0 + a1];
511 p[ 0] = VP8kclip1[q0 - a1];
512 p[ step] = VP8kclip1[q1 - a2];
513 p[ 2*step] = VP8kclip1[q2 - a3];
514 }
515
hev(const uint8_t * p,int step,int thresh)516 static WEBP_INLINE int hev(const uint8_t* p, int step, int thresh) {
517 const int p1 = p[-2*step], p0 = p[-step], q0 = p[0], q1 = p[step];
518 return (VP8kabs0[p1 - p0] > thresh) || (VP8kabs0[q1 - q0] > thresh);
519 }
520
needs_filter(const uint8_t * p,int step,int t)521 static WEBP_INLINE int needs_filter(const uint8_t* p, int step, int t) {
522 const int p1 = p[-2 * step], p0 = p[-step], q0 = p[0], q1 = p[step];
523 return ((4 * VP8kabs0[p0 - q0] + VP8kabs0[p1 - q1]) <= t);
524 }
525
needs_filter2(const uint8_t * p,int step,int t,int it)526 static WEBP_INLINE int needs_filter2(const uint8_t* p,
527 int step, int t, int it) {
528 const int p3 = p[-4 * step], p2 = p[-3 * step], p1 = p[-2 * step];
529 const int p0 = p[-step], q0 = p[0];
530 const int q1 = p[step], q2 = p[2 * step], q3 = p[3 * step];
531 if ((4 * VP8kabs0[p0 - q0] + VP8kabs0[p1 - q1]) > t) return 0;
532 return VP8kabs0[p3 - p2] <= it && VP8kabs0[p2 - p1] <= it &&
533 VP8kabs0[p1 - p0] <= it && VP8kabs0[q3 - q2] <= it &&
534 VP8kabs0[q2 - q1] <= it && VP8kabs0[q1 - q0] <= it;
535 }
536
537 //------------------------------------------------------------------------------
538 // Simple In-loop filtering (Paragraph 15.2)
539
SimpleVFilter16(uint8_t * p,int stride,int thresh)540 static void SimpleVFilter16(uint8_t* p, int stride, int thresh) {
541 int i;
542 const int thresh2 = 2 * thresh + 1;
543 for (i = 0; i < 16; ++i) {
544 if (needs_filter(p + i, stride, thresh2)) {
545 do_filter2(p + i, stride);
546 }
547 }
548 }
549
SimpleHFilter16(uint8_t * p,int stride,int thresh)550 static void SimpleHFilter16(uint8_t* p, int stride, int thresh) {
551 int i;
552 const int thresh2 = 2 * thresh + 1;
553 for (i = 0; i < 16; ++i) {
554 if (needs_filter(p + i * stride, 1, thresh2)) {
555 do_filter2(p + i * stride, 1);
556 }
557 }
558 }
559
SimpleVFilter16i(uint8_t * p,int stride,int thresh)560 static void SimpleVFilter16i(uint8_t* p, int stride, int thresh) {
561 int k;
562 for (k = 3; k > 0; --k) {
563 p += 4 * stride;
564 SimpleVFilter16(p, stride, thresh);
565 }
566 }
567
SimpleHFilter16i(uint8_t * p,int stride,int thresh)568 static void SimpleHFilter16i(uint8_t* p, int stride, int thresh) {
569 int k;
570 for (k = 3; k > 0; --k) {
571 p += 4;
572 SimpleHFilter16(p, stride, thresh);
573 }
574 }
575
576 //------------------------------------------------------------------------------
577 // Complex In-loop filtering (Paragraph 15.3)
578
FilterLoop26(uint8_t * p,int hstride,int vstride,int size,int thresh,int ithresh,int hev_thresh)579 static WEBP_INLINE void FilterLoop26(uint8_t* p,
580 int hstride, int vstride, int size,
581 int thresh, int ithresh, int hev_thresh) {
582 const int thresh2 = 2 * thresh + 1;
583 while (size-- > 0) {
584 if (needs_filter2(p, hstride, thresh2, ithresh)) {
585 if (hev(p, hstride, hev_thresh)) {
586 do_filter2(p, hstride);
587 } else {
588 do_filter6(p, hstride);
589 }
590 }
591 p += vstride;
592 }
593 }
594
FilterLoop24(uint8_t * p,int hstride,int vstride,int size,int thresh,int ithresh,int hev_thresh)595 static WEBP_INLINE void FilterLoop24(uint8_t* p,
596 int hstride, int vstride, int size,
597 int thresh, int ithresh, int hev_thresh) {
598 const int thresh2 = 2 * thresh + 1;
599 while (size-- > 0) {
600 if (needs_filter2(p, hstride, thresh2, ithresh)) {
601 if (hev(p, hstride, hev_thresh)) {
602 do_filter2(p, hstride);
603 } else {
604 do_filter4(p, hstride);
605 }
606 }
607 p += vstride;
608 }
609 }
610
611 // on macroblock edges
VFilter16(uint8_t * p,int stride,int thresh,int ithresh,int hev_thresh)612 static void VFilter16(uint8_t* p, int stride,
613 int thresh, int ithresh, int hev_thresh) {
614 FilterLoop26(p, stride, 1, 16, thresh, ithresh, hev_thresh);
615 }
616
HFilter16(uint8_t * p,int stride,int thresh,int ithresh,int hev_thresh)617 static void HFilter16(uint8_t* p, int stride,
618 int thresh, int ithresh, int hev_thresh) {
619 FilterLoop26(p, 1, stride, 16, thresh, ithresh, hev_thresh);
620 }
621
622 // on three inner edges
VFilter16i(uint8_t * p,int stride,int thresh,int ithresh,int hev_thresh)623 static void VFilter16i(uint8_t* p, int stride,
624 int thresh, int ithresh, int hev_thresh) {
625 int k;
626 for (k = 3; k > 0; --k) {
627 p += 4 * stride;
628 FilterLoop24(p, stride, 1, 16, thresh, ithresh, hev_thresh);
629 }
630 }
631
HFilter16i(uint8_t * p,int stride,int thresh,int ithresh,int hev_thresh)632 static void HFilter16i(uint8_t* p, int stride,
633 int thresh, int ithresh, int hev_thresh) {
634 int k;
635 for (k = 3; k > 0; --k) {
636 p += 4;
637 FilterLoop24(p, 1, stride, 16, thresh, ithresh, hev_thresh);
638 }
639 }
640
641 // 8-pixels wide variant, for chroma filtering
VFilter8(uint8_t * u,uint8_t * v,int stride,int thresh,int ithresh,int hev_thresh)642 static void VFilter8(uint8_t* u, uint8_t* v, int stride,
643 int thresh, int ithresh, int hev_thresh) {
644 FilterLoop26(u, stride, 1, 8, thresh, ithresh, hev_thresh);
645 FilterLoop26(v, stride, 1, 8, thresh, ithresh, hev_thresh);
646 }
647
HFilter8(uint8_t * u,uint8_t * v,int stride,int thresh,int ithresh,int hev_thresh)648 static void HFilter8(uint8_t* u, uint8_t* v, int stride,
649 int thresh, int ithresh, int hev_thresh) {
650 FilterLoop26(u, 1, stride, 8, thresh, ithresh, hev_thresh);
651 FilterLoop26(v, 1, stride, 8, thresh, ithresh, hev_thresh);
652 }
653
VFilter8i(uint8_t * u,uint8_t * v,int stride,int thresh,int ithresh,int hev_thresh)654 static void VFilter8i(uint8_t* u, uint8_t* v, int stride,
655 int thresh, int ithresh, int hev_thresh) {
656 FilterLoop24(u + 4 * stride, stride, 1, 8, thresh, ithresh, hev_thresh);
657 FilterLoop24(v + 4 * stride, stride, 1, 8, thresh, ithresh, hev_thresh);
658 }
659
HFilter8i(uint8_t * u,uint8_t * v,int stride,int thresh,int ithresh,int hev_thresh)660 static void HFilter8i(uint8_t* u, uint8_t* v, int stride,
661 int thresh, int ithresh, int hev_thresh) {
662 FilterLoop24(u + 4, 1, stride, 8, thresh, ithresh, hev_thresh);
663 FilterLoop24(v + 4, 1, stride, 8, thresh, ithresh, hev_thresh);
664 }
665
666 //------------------------------------------------------------------------------
667
668 VP8DecIdct2 VP8Transform;
669 VP8DecIdct VP8TransformAC3;
670 VP8DecIdct VP8TransformUV;
671 VP8DecIdct VP8TransformDC;
672 VP8DecIdct VP8TransformDCUV;
673
674 VP8LumaFilterFunc VP8VFilter16;
675 VP8LumaFilterFunc VP8HFilter16;
676 VP8ChromaFilterFunc VP8VFilter8;
677 VP8ChromaFilterFunc VP8HFilter8;
678 VP8LumaFilterFunc VP8VFilter16i;
679 VP8LumaFilterFunc VP8HFilter16i;
680 VP8ChromaFilterFunc VP8VFilter8i;
681 VP8ChromaFilterFunc VP8HFilter8i;
682 VP8SimpleFilterFunc VP8SimpleVFilter16;
683 VP8SimpleFilterFunc VP8SimpleHFilter16;
684 VP8SimpleFilterFunc VP8SimpleVFilter16i;
685 VP8SimpleFilterFunc VP8SimpleHFilter16i;
686
687 extern void VP8DspInitSSE2(void);
688 extern void VP8DspInitNEON(void);
689 extern void VP8DspInitMIPS32(void);
690
691 static volatile VP8CPUInfo dec_last_cpuinfo_used =
692 (VP8CPUInfo)&dec_last_cpuinfo_used;
693
VP8DspInit(void)694 void VP8DspInit(void) {
695 if (dec_last_cpuinfo_used == VP8GetCPUInfo) return;
696
697 VP8InitClipTables();
698
699 VP8TransformWHT = TransformWHT;
700 VP8Transform = TransformTwo;
701 VP8TransformUV = TransformUV;
702 VP8TransformDC = TransformDC;
703 VP8TransformDCUV = TransformDCUV;
704 VP8TransformAC3 = TransformAC3;
705
706 VP8VFilter16 = VFilter16;
707 VP8HFilter16 = HFilter16;
708 VP8VFilter8 = VFilter8;
709 VP8HFilter8 = HFilter8;
710 VP8VFilter16i = VFilter16i;
711 VP8HFilter16i = HFilter16i;
712 VP8VFilter8i = VFilter8i;
713 VP8HFilter8i = HFilter8i;
714 VP8SimpleVFilter16 = SimpleVFilter16;
715 VP8SimpleHFilter16 = SimpleHFilter16;
716 VP8SimpleVFilter16i = SimpleVFilter16i;
717 VP8SimpleHFilter16i = SimpleHFilter16i;
718
719 // If defined, use CPUInfo() to overwrite some pointers with faster versions.
720 if (VP8GetCPUInfo != NULL) {
721 #if defined(WEBP_USE_SSE2)
722 if (VP8GetCPUInfo(kSSE2)) {
723 VP8DspInitSSE2();
724 }
725 #elif defined(WEBP_USE_NEON)
726 if (VP8GetCPUInfo(kNEON)) {
727 VP8DspInitNEON();
728 }
729 #elif defined(WEBP_USE_MIPS32)
730 if (VP8GetCPUInfo(kMIPS32)) {
731 VP8DspInitMIPS32();
732 }
733 #endif
734 }
735 dec_last_cpuinfo_used = VP8GetCPUInfo;
736 }
737