1 /* 2 * Copyright (c) 2016, Alliance for Open Media. All rights reserved 3 * 4 * This source code is subject to the terms of the BSD 2 Clause License and 5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License 6 * was not distributed with this source code in the LICENSE file, you can 7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open 8 * Media Patent License 1.0 was not distributed with this source code in the 9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent. 10 * 11 * This code was originally written by: Nathan E. Egge, at the Daala 12 * project. 13 */ 14 #include <assert.h> 15 #include <math.h> 16 #include <stdlib.h> 17 #include <string.h> 18 19 #include "config/aom_config.h" 20 #include "config/aom_dsp_rtcd.h" 21 22 #include "aom_dsp/ssim.h" 23 #include "aom_ports/system_state.h" 24 25 typedef struct fs_level fs_level; 26 typedef struct fs_ctx fs_ctx; 27 28 #define SSIM_C1 (255 * 255 * 0.01 * 0.01) 29 #define SSIM_C2 (255 * 255 * 0.03 * 0.03) 30 #define SSIM_C1_10 (1023 * 1023 * 0.01 * 0.01) 31 #define SSIM_C1_12 (4095 * 4095 * 0.01 * 0.01) 32 #define SSIM_C2_10 (1023 * 1023 * 0.03 * 0.03) 33 #define SSIM_C2_12 (4095 * 4095 * 0.03 * 0.03) 34 35 #define FS_MINI(_a, _b) ((_a) < (_b) ? (_a) : (_b)) 36 #define FS_MAXI(_a, _b) ((_a) > (_b) ? (_a) : (_b)) 37 38 struct fs_level { 39 uint32_t *im1; 40 uint32_t *im2; 41 double *ssim; 42 int w; 43 int h; 44 }; 45 46 struct fs_ctx { 47 fs_level *level; 48 int nlevels; 49 unsigned *col_buf; 50 }; 51 52 static void fs_ctx_init(fs_ctx *_ctx, int _w, int _h, int _nlevels) { 53 unsigned char *data; 54 size_t data_size; 55 int lw; 56 int lh; 57 int l; 58 lw = (_w + 1) >> 1; 59 lh = (_h + 1) >> 1; 60 data_size = 61 _nlevels * sizeof(fs_level) + 2 * (lw + 8) * 8 * sizeof(*_ctx->col_buf); 62 for (l = 0; l < _nlevels; l++) { 63 size_t im_size; 64 size_t level_size; 65 im_size = lw * (size_t)lh; 66 level_size = 2 * im_size * sizeof(*_ctx->level[l].im1); 67 level_size += sizeof(*_ctx->level[l].ssim) - 1; 68 level_size /= sizeof(*_ctx->level[l].ssim); 69 level_size += im_size; 70 level_size *= sizeof(*_ctx->level[l].ssim); 71 data_size += level_size; 72 lw = (lw + 1) >> 1; 73 lh = (lh + 1) >> 1; 74 } 75 data = (unsigned char *)malloc(data_size); 76 _ctx->level = (fs_level *)data; 77 _ctx->nlevels = _nlevels; 78 data += _nlevels * sizeof(*_ctx->level); 79 lw = (_w + 1) >> 1; 80 lh = (_h + 1) >> 1; 81 for (l = 0; l < _nlevels; l++) { 82 size_t im_size; 83 size_t level_size; 84 _ctx->level[l].w = lw; 85 _ctx->level[l].h = lh; 86 im_size = lw * (size_t)lh; 87 level_size = 2 * im_size * sizeof(*_ctx->level[l].im1); 88 level_size += sizeof(*_ctx->level[l].ssim) - 1; 89 level_size /= sizeof(*_ctx->level[l].ssim); 90 level_size *= sizeof(*_ctx->level[l].ssim); 91 _ctx->level[l].im1 = (uint32_t *)data; 92 _ctx->level[l].im2 = _ctx->level[l].im1 + im_size; 93 data += level_size; 94 _ctx->level[l].ssim = (double *)data; 95 data += im_size * sizeof(*_ctx->level[l].ssim); 96 lw = (lw + 1) >> 1; 97 lh = (lh + 1) >> 1; 98 } 99 _ctx->col_buf = (unsigned *)data; 100 } 101 102 static void fs_ctx_clear(fs_ctx *_ctx) { free(_ctx->level); } 103 104 static void fs_downsample_level(fs_ctx *_ctx, int _l) { 105 const uint32_t *src1; 106 const uint32_t *src2; 107 uint32_t *dst1; 108 uint32_t *dst2; 109 int w2; 110 int h2; 111 int w; 112 int h; 113 int i; 114 int j; 115 w = _ctx->level[_l].w; 116 h = _ctx->level[_l].h; 117 dst1 = _ctx->level[_l].im1; 118 dst2 = _ctx->level[_l].im2; 119 w2 = _ctx->level[_l - 1].w; 120 h2 = _ctx->level[_l - 1].h; 121 src1 = _ctx->level[_l - 1].im1; 122 src2 = _ctx->level[_l - 1].im2; 123 for (j = 0; j < h; j++) { 124 int j0offs; 125 int j1offs; 126 j0offs = 2 * j * w2; 127 j1offs = FS_MINI(2 * j + 1, h2) * w2; 128 for (i = 0; i < w; i++) { 129 int i0; 130 int i1; 131 i0 = 2 * i; 132 i1 = FS_MINI(i0 + 1, w2); 133 dst1[j * w + i] = src1[j0offs + i0] + src1[j0offs + i1] + 134 src1[j1offs + i0] + src1[j1offs + i1]; 135 dst2[j * w + i] = src2[j0offs + i0] + src2[j0offs + i1] + 136 src2[j1offs + i0] + src2[j1offs + i1]; 137 } 138 } 139 } 140 141 static void fs_downsample_level0(fs_ctx *_ctx, const uint8_t *_src1, 142 int _s1ystride, const uint8_t *_src2, 143 int _s2ystride, int _w, int _h, uint32_t shift, 144 int buf_is_hbd) { 145 uint32_t *dst1; 146 uint32_t *dst2; 147 int w; 148 int h; 149 int i; 150 int j; 151 w = _ctx->level[0].w; 152 h = _ctx->level[0].h; 153 dst1 = _ctx->level[0].im1; 154 dst2 = _ctx->level[0].im2; 155 for (j = 0; j < h; j++) { 156 int j0; 157 int j1; 158 j0 = 2 * j; 159 j1 = FS_MINI(j0 + 1, _h); 160 for (i = 0; i < w; i++) { 161 int i0; 162 int i1; 163 i0 = 2 * i; 164 i1 = FS_MINI(i0 + 1, _w); 165 if (!buf_is_hbd) { 166 dst1[j * w + i] = 167 _src1[j0 * _s1ystride + i0] + _src1[j0 * _s1ystride + i1] + 168 _src1[j1 * _s1ystride + i0] + _src1[j1 * _s1ystride + i1]; 169 dst2[j * w + i] = 170 _src2[j0 * _s2ystride + i0] + _src2[j0 * _s2ystride + i1] + 171 _src2[j1 * _s2ystride + i0] + _src2[j1 * _s2ystride + i1]; 172 } else { 173 uint16_t *src1s = CONVERT_TO_SHORTPTR(_src1); 174 uint16_t *src2s = CONVERT_TO_SHORTPTR(_src2); 175 dst1[j * w + i] = (src1s[j0 * _s1ystride + i0] >> shift) + 176 (src1s[j0 * _s1ystride + i1] >> shift) + 177 (src1s[j1 * _s1ystride + i0] >> shift) + 178 (src1s[j1 * _s1ystride + i1] >> shift); 179 dst2[j * w + i] = (src2s[j0 * _s2ystride + i0] >> shift) + 180 (src2s[j0 * _s2ystride + i1] >> shift) + 181 (src2s[j1 * _s2ystride + i0] >> shift) + 182 (src2s[j1 * _s2ystride + i1] >> shift); 183 } 184 } 185 } 186 } 187 188 static void fs_apply_luminance(fs_ctx *_ctx, int _l, int bit_depth) { 189 unsigned *col_sums_x; 190 unsigned *col_sums_y; 191 uint32_t *im1; 192 uint32_t *im2; 193 double *ssim; 194 double c1; 195 int w; 196 int h; 197 int j0offs; 198 int j1offs; 199 int i; 200 int j; 201 double ssim_c1 = SSIM_C1; 202 203 if (bit_depth == 10) ssim_c1 = SSIM_C1_10; 204 if (bit_depth == 12) ssim_c1 = SSIM_C1_12; 205 206 w = _ctx->level[_l].w; 207 h = _ctx->level[_l].h; 208 col_sums_x = _ctx->col_buf; 209 col_sums_y = col_sums_x + w; 210 im1 = _ctx->level[_l].im1; 211 im2 = _ctx->level[_l].im2; 212 for (i = 0; i < w; i++) col_sums_x[i] = 5 * im1[i]; 213 for (i = 0; i < w; i++) col_sums_y[i] = 5 * im2[i]; 214 for (j = 1; j < 4; j++) { 215 j1offs = FS_MINI(j, h - 1) * w; 216 for (i = 0; i < w; i++) col_sums_x[i] += im1[j1offs + i]; 217 for (i = 0; i < w; i++) col_sums_y[i] += im2[j1offs + i]; 218 } 219 ssim = _ctx->level[_l].ssim; 220 c1 = (double)(ssim_c1 * 4096 * (1 << 4 * _l)); 221 for (j = 0; j < h; j++) { 222 unsigned mux; 223 unsigned muy; 224 int i0; 225 int i1; 226 mux = 5 * col_sums_x[0]; 227 muy = 5 * col_sums_y[0]; 228 for (i = 1; i < 4; i++) { 229 i1 = FS_MINI(i, w - 1); 230 mux += col_sums_x[i1]; 231 muy += col_sums_y[i1]; 232 } 233 for (i = 0; i < w; i++) { 234 ssim[j * w + i] *= (2 * mux * (double)muy + c1) / 235 (mux * (double)mux + muy * (double)muy + c1); 236 if (i + 1 < w) { 237 i0 = FS_MAXI(0, i - 4); 238 i1 = FS_MINI(i + 4, w - 1); 239 mux += col_sums_x[i1] - col_sums_x[i0]; 240 muy += col_sums_x[i1] - col_sums_x[i0]; 241 } 242 } 243 if (j + 1 < h) { 244 j0offs = FS_MAXI(0, j - 4) * w; 245 for (i = 0; i < w; i++) col_sums_x[i] -= im1[j0offs + i]; 246 for (i = 0; i < w; i++) col_sums_y[i] -= im2[j0offs + i]; 247 j1offs = FS_MINI(j + 4, h - 1) * w; 248 for (i = 0; i < w; i++) col_sums_x[i] += im1[j1offs + i]; 249 for (i = 0; i < w; i++) col_sums_y[i] += im2[j1offs + i]; 250 } 251 } 252 } 253 254 #define FS_COL_SET(_col, _joffs, _ioffs) \ 255 do { \ 256 unsigned gx; \ 257 unsigned gy; \ 258 gx = gx_buf[((j + (_joffs)) & 7) * stride + i + (_ioffs)]; \ 259 gy = gy_buf[((j + (_joffs)) & 7) * stride + i + (_ioffs)]; \ 260 col_sums_gx2[(_col)] = gx * (double)gx; \ 261 col_sums_gy2[(_col)] = gy * (double)gy; \ 262 col_sums_gxgy[(_col)] = gx * (double)gy; \ 263 } while (0) 264 265 #define FS_COL_ADD(_col, _joffs, _ioffs) \ 266 do { \ 267 unsigned gx; \ 268 unsigned gy; \ 269 gx = gx_buf[((j + (_joffs)) & 7) * stride + i + (_ioffs)]; \ 270 gy = gy_buf[((j + (_joffs)) & 7) * stride + i + (_ioffs)]; \ 271 col_sums_gx2[(_col)] += gx * (double)gx; \ 272 col_sums_gy2[(_col)] += gy * (double)gy; \ 273 col_sums_gxgy[(_col)] += gx * (double)gy; \ 274 } while (0) 275 276 #define FS_COL_SUB(_col, _joffs, _ioffs) \ 277 do { \ 278 unsigned gx; \ 279 unsigned gy; \ 280 gx = gx_buf[((j + (_joffs)) & 7) * stride + i + (_ioffs)]; \ 281 gy = gy_buf[((j + (_joffs)) & 7) * stride + i + (_ioffs)]; \ 282 col_sums_gx2[(_col)] -= gx * (double)gx; \ 283 col_sums_gy2[(_col)] -= gy * (double)gy; \ 284 col_sums_gxgy[(_col)] -= gx * (double)gy; \ 285 } while (0) 286 287 #define FS_COL_COPY(_col1, _col2) \ 288 do { \ 289 col_sums_gx2[(_col1)] = col_sums_gx2[(_col2)]; \ 290 col_sums_gy2[(_col1)] = col_sums_gy2[(_col2)]; \ 291 col_sums_gxgy[(_col1)] = col_sums_gxgy[(_col2)]; \ 292 } while (0) 293 294 #define FS_COL_HALVE(_col1, _col2) \ 295 do { \ 296 col_sums_gx2[(_col1)] = col_sums_gx2[(_col2)] * 0.5; \ 297 col_sums_gy2[(_col1)] = col_sums_gy2[(_col2)] * 0.5; \ 298 col_sums_gxgy[(_col1)] = col_sums_gxgy[(_col2)] * 0.5; \ 299 } while (0) 300 301 #define FS_COL_DOUBLE(_col1, _col2) \ 302 do { \ 303 col_sums_gx2[(_col1)] = col_sums_gx2[(_col2)] * 2; \ 304 col_sums_gy2[(_col1)] = col_sums_gy2[(_col2)] * 2; \ 305 col_sums_gxgy[(_col1)] = col_sums_gxgy[(_col2)] * 2; \ 306 } while (0) 307 308 static void fs_calc_structure(fs_ctx *_ctx, int _l, int bit_depth) { 309 uint32_t *im1; 310 uint32_t *im2; 311 unsigned *gx_buf; 312 unsigned *gy_buf; 313 double *ssim; 314 double col_sums_gx2[8]; 315 double col_sums_gy2[8]; 316 double col_sums_gxgy[8]; 317 double c2; 318 int stride; 319 int w; 320 int h; 321 int i; 322 int j; 323 double ssim_c2 = SSIM_C2; 324 if (bit_depth == 10) ssim_c2 = SSIM_C2_10; 325 if (bit_depth == 12) ssim_c2 = SSIM_C2_12; 326 327 w = _ctx->level[_l].w; 328 h = _ctx->level[_l].h; 329 im1 = _ctx->level[_l].im1; 330 im2 = _ctx->level[_l].im2; 331 ssim = _ctx->level[_l].ssim; 332 gx_buf = _ctx->col_buf; 333 stride = w + 8; 334 gy_buf = gx_buf + 8 * stride; 335 memset(gx_buf, 0, 2 * 8 * stride * sizeof(*gx_buf)); 336 c2 = ssim_c2 * (1 << 4 * _l) * 16 * 104; 337 for (j = 0; j < h + 4; j++) { 338 if (j < h - 1) { 339 for (i = 0; i < w - 1; i++) { 340 unsigned g1; 341 unsigned g2; 342 unsigned gx; 343 unsigned gy; 344 g1 = abs((int)im1[(j + 1) * w + i + 1] - (int)im1[j * w + i]); 345 g2 = abs((int)im1[(j + 1) * w + i] - (int)im1[j * w + i + 1]); 346 gx = 4 * FS_MAXI(g1, g2) + FS_MINI(g1, g2); 347 g1 = abs((int)im2[(j + 1) * w + i + 1] - (int)im2[j * w + i]); 348 g2 = abs((int)im2[(j + 1) * w + i] - (int)im2[j * w + i + 1]); 349 gy = 4 * FS_MAXI(g1, g2) + FS_MINI(g1, g2); 350 gx_buf[(j & 7) * stride + i + 4] = gx; 351 gy_buf[(j & 7) * stride + i + 4] = gy; 352 } 353 } else { 354 memset(gx_buf + (j & 7) * stride, 0, stride * sizeof(*gx_buf)); 355 memset(gy_buf + (j & 7) * stride, 0, stride * sizeof(*gy_buf)); 356 } 357 if (j >= 4) { 358 int k; 359 col_sums_gx2[3] = col_sums_gx2[2] = col_sums_gx2[1] = col_sums_gx2[0] = 0; 360 col_sums_gy2[3] = col_sums_gy2[2] = col_sums_gy2[1] = col_sums_gy2[0] = 0; 361 col_sums_gxgy[3] = col_sums_gxgy[2] = col_sums_gxgy[1] = 362 col_sums_gxgy[0] = 0; 363 for (i = 4; i < 8; i++) { 364 FS_COL_SET(i, -1, 0); 365 FS_COL_ADD(i, 0, 0); 366 for (k = 1; k < 8 - i; k++) { 367 FS_COL_DOUBLE(i, i); 368 FS_COL_ADD(i, -k - 1, 0); 369 FS_COL_ADD(i, k, 0); 370 } 371 } 372 for (i = 0; i < w; i++) { 373 double mugx2; 374 double mugy2; 375 double mugxgy; 376 mugx2 = col_sums_gx2[0]; 377 for (k = 1; k < 8; k++) mugx2 += col_sums_gx2[k]; 378 mugy2 = col_sums_gy2[0]; 379 for (k = 1; k < 8; k++) mugy2 += col_sums_gy2[k]; 380 mugxgy = col_sums_gxgy[0]; 381 for (k = 1; k < 8; k++) mugxgy += col_sums_gxgy[k]; 382 ssim[(j - 4) * w + i] = (2 * mugxgy + c2) / (mugx2 + mugy2 + c2); 383 if (i + 1 < w) { 384 FS_COL_SET(0, -1, 1); 385 FS_COL_ADD(0, 0, 1); 386 FS_COL_SUB(2, -3, 2); 387 FS_COL_SUB(2, 2, 2); 388 FS_COL_HALVE(1, 2); 389 FS_COL_SUB(3, -4, 3); 390 FS_COL_SUB(3, 3, 3); 391 FS_COL_HALVE(2, 3); 392 FS_COL_COPY(3, 4); 393 FS_COL_DOUBLE(4, 5); 394 FS_COL_ADD(4, -4, 5); 395 FS_COL_ADD(4, 3, 5); 396 FS_COL_DOUBLE(5, 6); 397 FS_COL_ADD(5, -3, 6); 398 FS_COL_ADD(5, 2, 6); 399 FS_COL_DOUBLE(6, 7); 400 FS_COL_ADD(6, -2, 7); 401 FS_COL_ADD(6, 1, 7); 402 FS_COL_SET(7, -1, 8); 403 FS_COL_ADD(7, 0, 8); 404 } 405 } 406 } 407 } 408 } 409 410 #define FS_NLEVELS (4) 411 412 /*These weights were derived from the default weights found in Wang's original 413 Matlab implementation: {0.0448, 0.2856, 0.2363, 0.1333}. 414 We drop the finest scale and renormalize the rest to sum to 1.*/ 415 416 static const double FS_WEIGHTS[FS_NLEVELS] = { 417 0.2989654541015625, 0.3141326904296875, 0.2473602294921875, 0.1395416259765625 418 }; 419 420 static double fs_average(fs_ctx *_ctx, int _l) { 421 double *ssim; 422 double ret; 423 int w; 424 int h; 425 int i; 426 int j; 427 w = _ctx->level[_l].w; 428 h = _ctx->level[_l].h; 429 ssim = _ctx->level[_l].ssim; 430 ret = 0; 431 for (j = 0; j < h; j++) 432 for (i = 0; i < w; i++) ret += ssim[j * w + i]; 433 return pow(ret / (w * h), FS_WEIGHTS[_l]); 434 } 435 436 static double convert_ssim_db(double _ssim, double _weight) { 437 assert(_weight >= _ssim); 438 if ((_weight - _ssim) < 1e-10) return MAX_SSIM_DB; 439 return 10 * (log10(_weight) - log10(_weight - _ssim)); 440 } 441 442 static double calc_ssim(const uint8_t *_src, int _systride, const uint8_t *_dst, 443 int _dystride, int _w, int _h, uint32_t _bd, 444 uint32_t _shift, int buf_is_hbd) { 445 fs_ctx ctx; 446 double ret; 447 int l; 448 ret = 1; 449 fs_ctx_init(&ctx, _w, _h, FS_NLEVELS); 450 fs_downsample_level0(&ctx, _src, _systride, _dst, _dystride, _w, _h, _shift, 451 buf_is_hbd); 452 for (l = 0; l < FS_NLEVELS - 1; l++) { 453 fs_calc_structure(&ctx, l, _bd); 454 ret *= fs_average(&ctx, l); 455 fs_downsample_level(&ctx, l + 1); 456 } 457 fs_calc_structure(&ctx, l, _bd); 458 fs_apply_luminance(&ctx, l, _bd); 459 ret *= fs_average(&ctx, l); 460 fs_ctx_clear(&ctx); 461 return ret; 462 } 463 464 double aom_calc_fastssim(const YV12_BUFFER_CONFIG *source, 465 const YV12_BUFFER_CONFIG *dest, double *ssim_y, 466 double *ssim_u, double *ssim_v, uint32_t bd, 467 uint32_t in_bd) { 468 double ssimv; 469 uint32_t bd_shift = 0; 470 aom_clear_system_state(); 471 assert(bd >= in_bd); 472 assert(source->flags == dest->flags); 473 int buf_is_hbd = source->flags & YV12_FLAG_HIGHBITDEPTH; 474 bd_shift = bd - in_bd; 475 476 *ssim_y = calc_ssim(source->y_buffer, source->y_stride, dest->y_buffer, 477 dest->y_stride, source->y_crop_width, 478 source->y_crop_height, in_bd, bd_shift, buf_is_hbd); 479 *ssim_u = calc_ssim(source->u_buffer, source->uv_stride, dest->u_buffer, 480 dest->uv_stride, source->uv_crop_width, 481 source->uv_crop_height, in_bd, bd_shift, buf_is_hbd); 482 *ssim_v = calc_ssim(source->v_buffer, source->uv_stride, dest->v_buffer, 483 dest->uv_stride, source->uv_crop_width, 484 source->uv_crop_height, in_bd, bd_shift, buf_is_hbd); 485 ssimv = (*ssim_y) * .8 + .1 * ((*ssim_u) + (*ssim_v)); 486 return convert_ssim_db(ssimv, 1.0); 487 } 488
