FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavfilter/vf_ssim360.c
Date: 2024-11-20 23:03:26
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1 /**
2 * Copyright (c) 2015-2021, Facebook, Inc.
3 * All rights reserved.
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /* Computes the Structural Similarity Metric between two 360 video streams.
23 * original SSIM algorithm:
24 * Z. Wang, A. C. Bovik, H. R. Sheikh and E. P. Simoncelli,
25 * "Image quality assessment: From error visibility to structural similarity,"
26 * IEEE Transactions on Image Processing, vol. 13, no. 4, pp. 600-612, Apr. 2004.
27 *
28 * To improve speed, this implementation uses the standard approximation of
29 * overlapped 8x8 block sums, rather than the original gaussian weights.
30 *
31 * To address warping from 360 projections for videos with same
32 * projection and resolution, the 8x8 blocks sampled are weighted by
33 * their location in the image.
34 *
35 * To apply SSIM across projections and video sizes, we render the video on to
36 * a flat "tape" from which the 8x8 are selected and compared.
37 */
38
39 /*
40 * @file
41 * Caculate the SSIM between two input 360 videos.
42 */
43
44 #include <math.h>
45
46 #include "libavutil/avstring.h"
47 #include "libavutil/file_open.h"
48 #include "libavutil/mem.h"
49 #include "libavutil/opt.h"
50 #include "libavutil/pixdesc.h"
51
52 #include "avfilter.h"
53 #include "drawutils.h"
54 #include "filters.h"
55 #include "framesync.h"
56
57 #define RIGHT 0
58 #define LEFT 1
59 #define TOP 2
60 #define BOTTOM 3
61 #define FRONT 4
62 #define BACK 5
63
64 #define DEFAULT_HEATMAP_W 32
65 #define DEFAULT_HEATMAP_H 16
66
67 #define M_PI_F ((float)M_PI)
68 #define M_PI_2_F ((float)M_PI_2)
69 #define M_PI_4_F ((float)M_PI_4)
70 #define M_SQRT2_F ((float)M_SQRT2)
71
72 #define DEFAULT_EXPANSION_COEF 1.01f
73
74 #define BARREL_THETA_RANGE (DEFAULT_EXPANSION_COEF * 2.0f * M_PI_F)
75 #define BARREL_PHI_RANGE (DEFAULT_EXPANSION_COEF * M_PI_2_F)
76
77 // Use fixed-point with 16 bit precision for fast bilinear math
78 #define FIXED_POINT_PRECISION 16
79
80 // Use 1MB per channel for the histogram to get 5-digit precise SSIM value
81 #define SSIM360_HIST_SIZE 131072
82
83 // The last number is a marker < 0 to mark end of list
84 static const double PERCENTILE_LIST[] = {
85 1.0, 0.9, 0.8, 0.7, 0.6,
86 0.5, 0.4, 0.3, 0.2, 0.1, 0, -1
87 };
88
89 typedef enum StereoFormat {
90 STEREO_FORMAT_TB,
91 STEREO_FORMAT_LR,
92 STEREO_FORMAT_MONO,
93 STEREO_FORMAT_N
94 } StereoFormat;
95
96 typedef enum Projection {
97 PROJECTION_CUBEMAP32,
98 PROJECTION_CUBEMAP23,
99 PROJECTION_BARREL,
100 PROJECTION_BARREL_SPLIT,
101 PROJECTION_EQUIRECT,
102 PROJECTION_N
103 } Projection;
104
105 typedef struct Map2D {
106 int w, h;
107 double *value;
108 } Map2D;
109
110 typedef struct HeatmapList {
111 Map2D map;
112 struct HeatmapList *next;
113 } HeatmapList;
114
115 typedef struct SampleParams {
116 int stride;
117 int planewidth;
118 int planeheight;
119 int x_image_offset;
120 int y_image_offset;
121 int x_image_range;
122 int y_image_range;
123 int projection;
124 float expand_coef;
125 } SampleParams;
126
127 typedef struct BilinearMap {
128 // Indices to the 4 samples to compute bilinear
129 int tli;
130 int tri;
131 int bli;
132 int bri;
133
134 // Fixed point factors with which the above 4 sample vector's
135 // dot product needs to be computed for the final bilinear value
136 int tlf;
137 int trf;
138 int blf;
139 int brf;
140 } BilinearMap;
141
142 typedef struct SSIM360Context {
143 const AVClass *class;
144
145 FFFrameSync fs;
146 // Stats file configuration
147 FILE *stats_file;
148 char *stats_file_str;
149
150 // Component properties
151 int nb_components;
152 double coefs[4];
153 char comps[4];
154 int max;
155
156 // Channel configuration & properties
157 int compute_chroma;
158
159 int is_rgb;
160 uint8_t rgba_map[4];
161
162 // Standard SSIM computation configuration & workspace
163 uint64_t frame_skip_ratio;
164
165 int *temp;
166 uint64_t nb_ssim_frames;
167 uint64_t nb_net_frames;
168 double ssim360[4], ssim360_total;
169 double *ssim360_hist[4];
170 double ssim360_hist_net[4];
171 double ssim360_percentile_sum[4][256];
172
173 // 360 projection configuration & workspace
174 int ref_projection;
175 int main_projection;
176 int ref_stereo_format;
177 int main_stereo_format;
178 float ref_pad;
179 float main_pad;
180 int use_tape;
181 char *heatmap_str;
182 int default_heatmap_w;
183 int default_heatmap_h;
184
185 Map2D density;
186 HeatmapList *heatmaps;
187 int ref_planewidth[4];
188 int ref_planeheight[4];
189 int main_planewidth[4];
190 int main_planeheight[4];
191 int tape_length[4];
192 BilinearMap *ref_tape_map[4][2];
193 BilinearMap *main_tape_map[4][2];
194 float angular_resolution[4][2];
195 double (*ssim360_plane)(
196 uint8_t *main, int main_stride,
197 uint8_t *ref, int ref_stride,
198 int width, int height, void *temp,
199 int max, Map2D density);
200 } SSIM360Context;
201
202 #define OFFSET(x) offsetof(SSIM360Context, x)
203 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
204
205 static const AVOption ssim360_options[] = {
206 { "stats_file", "Set file where to store per-frame difference information",
207 OFFSET(stats_file_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
208 { "f", "Set file where to store per-frame difference information",
209 OFFSET(stats_file_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
210
211 { "compute_chroma",
212 "Specifies if non-luma channels must be computed",
213 OFFSET(compute_chroma), AV_OPT_TYPE_INT, {.i64 = 1},
214 0, 1, .flags = FLAGS },
215
216 { "frame_skip_ratio",
217 "Specifies the number of frames to be skipped from evaluation, for every evaluated frame",
218 OFFSET(frame_skip_ratio), AV_OPT_TYPE_INT, {.i64 = 0},
219 0, 1000000, .flags = FLAGS },
220
221 { "ref_projection", "projection of the reference video",
222 OFFSET(ref_projection), AV_OPT_TYPE_INT, {.i64 = PROJECTION_EQUIRECT},
223 0, PROJECTION_N - 1, .flags = FLAGS, .unit = "projection" },
224
225 { "e", "equirectangular", 0, AV_OPT_TYPE_CONST, {.i64 = PROJECTION_EQUIRECT}, 0, 0, FLAGS, .unit = "projection" },
226 { "equirect", "equirectangular", 0, AV_OPT_TYPE_CONST, {.i64 = PROJECTION_EQUIRECT}, 0, 0, FLAGS, .unit = "projection" },
227 { "c3x2", "cubemap 3x2", 0, AV_OPT_TYPE_CONST, {.i64 = PROJECTION_CUBEMAP32}, 0, 0, FLAGS, .unit = "projection" },
228 { "c2x3", "cubemap 2x3", 0, AV_OPT_TYPE_CONST, {.i64 = PROJECTION_CUBEMAP23}, 0, 0, FLAGS, .unit = "projection" },
229 { "barrel", "barrel facebook's 360 format", 0, AV_OPT_TYPE_CONST, {.i64 = PROJECTION_BARREL}, 0, 0, FLAGS, .unit = "projection" },
230 { "barrelsplit", "barrel split facebook's 360 format", 0, AV_OPT_TYPE_CONST, {.i64 = PROJECTION_BARREL_SPLIT}, 0, 0, FLAGS, .unit = "projection" },
231
232 { "main_projection", "projection of the main video",
233 OFFSET(main_projection), AV_OPT_TYPE_INT, {.i64 = PROJECTION_N},
234 0, PROJECTION_N, .flags = FLAGS, .unit = "projection" },
235
236 { "ref_stereo", "stereo format of the reference video",
237 OFFSET(ref_stereo_format), AV_OPT_TYPE_INT, {.i64 = STEREO_FORMAT_MONO},
238 0, STEREO_FORMAT_N - 1, .flags = FLAGS, .unit = "stereo_format" },
239
240 { "mono", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = STEREO_FORMAT_MONO }, 0, 0, FLAGS, .unit = "stereo_format" },
241 { "tb", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = STEREO_FORMAT_TB }, 0, 0, FLAGS, .unit = "stereo_format" },
242 { "lr", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = STEREO_FORMAT_LR }, 0, 0, FLAGS, .unit = "stereo_format" },
243
244 { "main_stereo", "stereo format of main video",
245 OFFSET(main_stereo_format), AV_OPT_TYPE_INT, {.i64 = STEREO_FORMAT_N},
246 0, STEREO_FORMAT_N, .flags = FLAGS, .unit = "stereo_format" },
247
248 { "ref_pad",
249 "Expansion (padding) coefficient for each cube face of the reference video",
250 OFFSET(ref_pad), AV_OPT_TYPE_FLOAT, {.dbl = .0f}, 0, 10, .flags = FLAGS },
251
252 { "main_pad",
253 "Expansion (padding) coeffiecient for each cube face of the main video",
254 OFFSET(main_pad), AV_OPT_TYPE_FLOAT, {.dbl = .0f}, 0, 10, .flags = FLAGS },
255
256 { "use_tape",
257 "Specifies if the tape based SSIM 360 algorithm must be used independent of the input video types",
258 OFFSET(use_tape), AV_OPT_TYPE_INT, {.i64 = 0},
259 0, 1, .flags = FLAGS },
260
261 { "heatmap_str",
262 "Heatmap data for view-based evaluation. For heatmap file format, please refer to EntSphericalVideoHeatmapData.",
263 OFFSET(heatmap_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, .flags = FLAGS },
264
265 { "default_heatmap_width",
266 "Default heatmap dimension. Will be used when dimension is not specified in heatmap data.",
267 OFFSET(default_heatmap_w), AV_OPT_TYPE_INT, {.i64 = 32}, 1, 4096, .flags = FLAGS },
268
269 { "default_heatmap_height",
270 "Default heatmap dimension. Will be used when dimension is not specified in heatmap data.",
271 OFFSET(default_heatmap_h), AV_OPT_TYPE_INT, {.i64 = 16}, 1, 4096, .flags = FLAGS },
272
273 { NULL }
274 };
275
276 FRAMESYNC_DEFINE_CLASS(ssim360, SSIM360Context, fs);
277
278 static void set_meta(AVDictionary **metadata, const char *key, char comp, float d)
279 {
280 char value[128];
281 snprintf(value, sizeof(value), "%0.2f", d);
282 if (comp) {
283 char key2[128];
284 snprintf(key2, sizeof(key2), "%s%c", key, comp);
285 av_dict_set(metadata, key2, value, 0);
286 } else {
287 av_dict_set(metadata, key, value, 0);
288 }
289 }
290
291 static void map_uninit(Map2D *map)
292 {
293 av_freep(&map->value);
294 }
295
296 static int map_init(Map2D *map, int w, int h)
297 {
298 map->value = av_calloc(h * w, sizeof(*map->value));
299 if (!map->value)
300 return AVERROR(ENOMEM);
301
302 map->h = h;
303 map->w = w;
304
305 return 0;
306 }
307
308 static void map_list_free(HeatmapList **pl)
309 {
310 HeatmapList *l = *pl;
311
312 while (l) {
313 HeatmapList *next = l->next;
314 map_uninit(&l->map);
315 av_freep(&l);
316 l = next;
317 }
318
319 *pl = NULL;
320 }
321
322 static int map_alloc(HeatmapList **pl, int w, int h)
323 {
324 HeatmapList *l;
325 int ret;
326
327 l = av_mallocz(sizeof(*l));
328 if (!l)
329 return AVERROR(ENOMEM);
330
331 ret = map_init(&l->map, w, h);
332 if (ret < 0) {
333 av_freep(&l);
334 return ret;
335 }
336
337 *pl = l;
338 return 0;
339 }
340
341 static void
342 ssim360_4x4xn_16bit(const uint8_t *main8, ptrdiff_t main_stride,
343 const uint8_t *ref8, ptrdiff_t ref_stride,
344 int64_t (*sums)[4], int width)
345 {
346 const uint16_t *main16 = (const uint16_t *)main8;
347 const uint16_t *ref16 = (const uint16_t *)ref8;
348
349 main_stride >>= 1;
350 ref_stride >>= 1;
351
352 for (int z = 0; z < width; z++) {
353 uint64_t s1 = 0, s2 = 0, ss = 0, s12 = 0;
354
355 for (int y = 0; y < 4; y++) {
356 for (int x = 0; x < 4; x++) {
357 unsigned a = main16[x + y * main_stride];
358 unsigned b = ref16[x + y * ref_stride];
359
360 s1 += a;
361 s2 += b;
362 ss += a*a;
363 ss += b*b;
364 s12 += a*b;
365 }
366 }
367
368 sums[z][0] = s1;
369 sums[z][1] = s2;
370 sums[z][2] = ss;
371 sums[z][3] = s12;
372 main16 += 4;
373 ref16 += 4;
374 }
375 }
376
377 static void
378 ssim360_4x4xn_8bit(const uint8_t *main, ptrdiff_t main_stride,
379 const uint8_t *ref, ptrdiff_t ref_stride,
380 int (*sums)[4], int width)
381 {
382 for (int z = 0; z < width; z++) {
383 uint32_t s1 = 0, s2 = 0, ss = 0, s12 = 0;
384
385 for (int y = 0; y < 4; y++) {
386 for (int x = 0; x < 4; x++) {
387 int a = main[x + y * main_stride];
388 int b = ref[x + y * ref_stride];
389
390 s1 += a;
391 s2 += b;
392 ss += a*a;
393 ss += b*b;
394 s12 += a*b;
395 }
396 }
397
398 sums[z][0] = s1;
399 sums[z][1] = s2;
400 sums[z][2] = ss;
401 sums[z][3] = s12;
402 main += 4;
403 ref += 4;
404 }
405 }
406
407 static float ssim360_end1x(int64_t s1, int64_t s2, int64_t ss, int64_t s12, int max)
408 {
409 int64_t ssim_c1 = (int64_t)(.01 * .01 * max * max * 64 + .5);
410 int64_t ssim_c2 = (int64_t)(.03 * .03 * max * max * 64 * 63 + .5);
411
412 int64_t fs1 = s1;
413 int64_t fs2 = s2;
414 int64_t fss = ss;
415 int64_t fs12 = s12;
416 int64_t vars = fss * 64 - fs1 * fs1 - fs2 * fs2;
417 int64_t covar = fs12 * 64 - fs1 * fs2;
418
419 return (float)(2 * fs1 * fs2 + ssim_c1) * (float)(2 * covar + ssim_c2)
420 / ((float)(fs1 * fs1 + fs2 * fs2 + ssim_c1) * (float)(vars + ssim_c2));
421 }
422
423 static float ssim360_end1(int s1, int s2, int ss, int s12)
424 {
425 static const int ssim_c1 = (int)(.01*.01*255*255*64 + .5);
426 static const int ssim_c2 = (int)(.03*.03*255*255*64*63 + .5);
427
428 int fs1 = s1;
429 int fs2 = s2;
430 int fss = ss;
431 int fs12 = s12;
432 int vars = fss * 64 - fs1 * fs1 - fs2 * fs2;
433 int covar = fs12 * 64 - fs1 * fs2;
434
435 return (float)(2 * fs1 * fs2 + ssim_c1) * (float)(2 * covar + ssim_c2)
436 / ((float)(fs1 * fs1 + fs2 * fs2 + ssim_c1) * (float)(vars + ssim_c2));
437 }
438
439 static double
440 ssim360_endn_16bit(const int64_t (*sum0)[4], const int64_t (*sum1)[4],
441 int width, int max,
442 double *density_map, int map_width, double *total_weight)
443 {
444 double ssim360 = 0.0, weight;
445
446 for (int i = 0; i < width; i++) {
447 weight = density_map ? density_map[(int) ((0.5 + i) / width * map_width)] : 1.0;
448 ssim360 += weight * ssim360_end1x(
449 sum0[i][0] + sum0[i + 1][0] + sum1[i][0] + sum1[i + 1][0],
450 sum0[i][1] + sum0[i + 1][1] + sum1[i][1] + sum1[i + 1][1],
451 sum0[i][2] + sum0[i + 1][2] + sum1[i][2] + sum1[i + 1][2],
452 sum0[i][3] + sum0[i + 1][3] + sum1[i][3] + sum1[i + 1][3],
453 max);
454 *total_weight += weight;
455 }
456 return ssim360;
457 }
458
459 static double
460 ssim360_endn_8bit(const int (*sum0)[4], const int (*sum1)[4], int width,
461 double *density_map, int map_width, double *total_weight)
462 {
463 double ssim360 = 0.0, weight;
464
465 for (int i = 0; i < width; i++) {
466 weight = density_map ? density_map[(int) ((0.5 + i) / width * map_width)] : 1.0;
467 ssim360 += weight * ssim360_end1(
468 sum0[i][0] + sum0[i + 1][0] + sum1[i][0] + sum1[i + 1][0],
469 sum0[i][1] + sum0[i + 1][1] + sum1[i][1] + sum1[i + 1][1],
470 sum0[i][2] + sum0[i + 1][2] + sum1[i][2] + sum1[i + 1][2],
471 sum0[i][3] + sum0[i + 1][3] + sum1[i][3] + sum1[i + 1][3]);
472 *total_weight += weight;
473 }
474 return ssim360;
475 }
476
477 static double
478 ssim360_plane_16bit(uint8_t *main, int main_stride,
479 uint8_t *ref, int ref_stride,
480 int width, int height, void *temp,
481 int max, Map2D density)
482 {
483 int z = 0;
484 double ssim360 = 0.0;
485 int64_t (*sum0)[4] = temp;
486 int64_t (*sum1)[4] = sum0 + (width >> 2) + 3;
487 double total_weight = 0.0;
488
489 width >>= 2;
490 height >>= 2;
491
492 for (int y = 1; y < height; y++) {
493 for (; z <= y; z++) {
494 FFSWAP(void*, sum0, sum1);
495 ssim360_4x4xn_16bit(&main[4 * z * main_stride], main_stride,
496 &ref[4 * z * ref_stride], ref_stride,
497 sum0, width);
498 }
499 ssim360 += ssim360_endn_16bit(
500 (const int64_t (*)[4])sum0, (const int64_t (*)[4])sum1,
501 width - 1, max,
502 density.value ? density.value + density.w * ((int) ((z - 1.0) / height * density.h)) : NULL,
503 density.w, &total_weight);
504 }
505
506 return (double) (ssim360 / total_weight);
507 }
508
509 static double
510 ssim360_plane_8bit(uint8_t *main, int main_stride,
511 uint8_t *ref, int ref_stride,
512 int width, int height, void *temp,
513 int max, Map2D density)
514 {
515 int z = 0;
516 double ssim360 = 0.0;
517 int (*sum0)[4] = temp;
518 int (*sum1)[4] = sum0 + (width >> 2) + 3;
519 double total_weight = 0.0;
520
521 width >>= 2;
522 height >>= 2;
523
524 for (int y = 1; y < height; y++) {
525 for (; z <= y; z++) {
526 FFSWAP(void*, sum0, sum1);
527 ssim360_4x4xn_8bit(
528 &main[4 * z * main_stride], main_stride,
529 &ref[4 * z * ref_stride], ref_stride,
530 sum0, width);
531 }
532 ssim360 += ssim360_endn_8bit(
533 (const int (*)[4])sum0, (const int (*)[4])sum1, width - 1,
534 density.value ? density.value + density.w * ((int) ((z - 1.0) / height * density.h)) : NULL,
535 density.w, &total_weight);
536 }
537
538 return (double) (ssim360 / total_weight);
539 }
540
541 static double ssim360_db(double ssim360, double weight)
542 {
543 return 10 * log10(weight / (weight - ssim360));
544 }
545
546 static int get_bilinear_sample(const uint8_t *data, BilinearMap *m, int max_value)
547 {
548 static const int fixed_point_half = 1 << (FIXED_POINT_PRECISION - 1);
549 static const int inv_byte_mask = UINT_MAX << 8;
550
551 int tl, tr, bl, br, v;
552
553 if (max_value & inv_byte_mask) {
554 uint16_t *data16 = (uint16_t *)data;
555 tl = data16[m->tli];
556 tr = data16[m->tri];
557 bl = data16[m->bli];
558 br = data16[m->bri];
559 } else {
560 tl = data[m->tli];
561 tr = data[m->tri];
562 bl = data[m->bli];
563 br = data[m->bri];
564 }
565
566 v = m->tlf * tl +
567 m->trf * tr +
568 m->blf * bl +
569 m->brf * br;
570
571 // Round by half, and revert the fixed-point offset
572 return ((v + fixed_point_half) >> FIXED_POINT_PRECISION) & max_value;
573 }
574
575 static void
576 ssim360_4x4x2_tape(const uint8_t *main, BilinearMap *main_maps,
577 const uint8_t *ref, BilinearMap *ref_maps,
578 int offset_y, int max_value, int (*sums)[4])
579 {
580 int offset_x = 0;
581
582 // Two blocks along the width
583 for (int z = 0; z < 2; z++) {
584 int s1 = 0, s2 = 0, ss = 0, s12 = 0;
585
586 // 4 pixel block from (offset_x, offset_y)
587 for (int y = offset_y; y < offset_y + 4; y++) {
588 int y_stride = y << 3;
589 for (int x = offset_x; x < offset_x + 4; x++) {
590 int map_index = x + y_stride;
591 int a = get_bilinear_sample(main, main_maps + map_index, max_value);
592 int b = get_bilinear_sample(ref, ref_maps + map_index, max_value);
593
594 s1 += a;
595 s2 += b;
596 ss += a*a;
597 ss += b*b;
598 s12 += a*b;
599 }
600 }
601
602 sums[z][0] = s1;
603 sums[z][1] = s2;
604 sums[z][2] = ss;
605 sums[z][3] = s12;
606
607 offset_x += 4;
608 }
609 }
610
611 static float get_radius_between_negative_and_positive_pi(float theta)
612 {
613 int floor_theta_by_2pi, floor_theta_by_pi;
614
615 // Convert theta to range [0, 2*pi]
616 floor_theta_by_2pi = (int)(theta / (2.0f * M_PI_F)) - (theta < 0.0f);
617 theta -= 2.0f * M_PI_F * floor_theta_by_2pi;
618
619 // Convert theta to range [-pi, pi]
620 floor_theta_by_pi = theta / M_PI_F;
621 theta -= 2.0f * M_PI_F * floor_theta_by_pi;
622 return FFMIN(M_PI_F, FFMAX(-M_PI_F, theta));
623 }
624
625 static float get_heat(HeatmapList *heatmaps, float angular_resoluation, float norm_tape_pos)
626 {
627 float pitch, yaw, norm_pitch, norm_yaw;
628 int w, h;
629
630 if (!heatmaps)
631 return 1.0f;
632
633 pitch = asinf(norm_tape_pos*2);
634 yaw = M_PI_2_F * pitch / angular_resoluation;
635 yaw = get_radius_between_negative_and_positive_pi(yaw);
636
637 // normalize into [0,1]
638 norm_pitch = 1.0f - (pitch / M_PI_F + 0.5f);
639 norm_yaw = yaw / 2.0f / M_PI_F + 0.5f;
640
641 // get heat on map
642 w = FFMIN(heatmaps->map.w - 1, FFMAX(0, heatmaps->map.w * norm_yaw));
643 h = FFMIN(heatmaps->map.h - 1, FFMAX(0, heatmaps->map.h * norm_pitch));
644 return heatmaps->map.value[h * heatmaps->map.w + w];
645 }
646
647 static double
648 ssim360_tape(uint8_t *main, BilinearMap *main_maps,
649 uint8_t *ref, BilinearMap *ref_maps,
650 int tape_length, int max_value, void *temp,
651 double *ssim360_hist, double *ssim360_hist_net,
652 float angular_resolution, HeatmapList *heatmaps)
653 {
654 int horizontal_block_count = 2;
655 int vertical_block_count = tape_length >> 2;
656
657 int z = 0, y;
658 // Since the tape will be very long and we need to average over all 8x8 blocks, use double
659 double ssim360 = 0.0;
660 double sum_weight = 0.0;
661
662 int (*sum0)[4] = temp;
663 int (*sum1)[4] = sum0 + horizontal_block_count + 3;
664
665 for (y = 1; y < vertical_block_count; y++) {
666 int fs1, fs2, fss, fs12, hist_index;
667 float norm_tape_pos, weight;
668 double sample_ssim360;
669
670 for (; z <= y; z++) {
671 FFSWAP(void*, sum0, sum1);
672 ssim360_4x4x2_tape(main, main_maps, ref, ref_maps, z*4, max_value, sum0);
673 }
674
675 // Given we have only one 8x8 block, following sums fit within 26 bits even for 10bit videos
676 fs1 = sum0[0][0] + sum0[1][0] + sum1[0][0] + sum1[1][0];
677 fs2 = sum0[0][1] + sum0[1][1] + sum1[0][1] + sum1[1][1];
678 fss = sum0[0][2] + sum0[1][2] + sum1[0][2] + sum1[1][2];
679 fs12 = sum0[0][3] + sum0[1][3] + sum1[0][3] + sum1[1][3];
680
681 if (max_value > 255) {
682 // Since we need high precision to multiply fss / fs12 by 64, use double
683 double ssim_c1_d = .01*.01*64*max_value*max_value;
684 double ssim_c2_d = .03*.03*64*63*max_value*max_value;
685
686 double vars = 64. * fss - 1. * fs1 * fs1 - 1. * fs2 * fs2;
687 double covar = 64. * fs12 - 1.*fs1 * fs2;
688 sample_ssim360 = (2. * fs1 * fs2 + ssim_c1_d) * (2. * covar + ssim_c2_d)
689 / ((1. * fs1 * fs1 + 1. * fs2 * fs2 + ssim_c1_d) * (1. * vars + ssim_c2_d));
690 } else {
691 static const int ssim_c1 = (int)(.01*.01*255*255*64 + .5);
692 static const int ssim_c2 = (int)(.03*.03*255*255*64*63 + .5);
693
694 int vars = fss * 64 - fs1 * fs1 - fs2 * fs2;
695 int covar = fs12 * 64 - fs1 * fs2;
696 sample_ssim360 = (double)(2 * fs1 * fs2 + ssim_c1) * (double)(2 * covar + ssim_c2)
697 / ((double)(fs1 * fs1 + fs2 * fs2 + ssim_c1) * (double)(vars + ssim_c2));
698 }
699
700 hist_index = (int)(sample_ssim360 * ((double)SSIM360_HIST_SIZE - .5));
701 hist_index = av_clip(hist_index, 0, SSIM360_HIST_SIZE - 1);
702
703 norm_tape_pos = (y - 0.5f) / (vertical_block_count - 1.0f) - 0.5f;
704 // weight from an input heatmap if available, otherwise weight = 1.0
705 weight = get_heat(heatmaps, angular_resolution, norm_tape_pos);
706 ssim360_hist[hist_index] += weight;
707 *ssim360_hist_net += weight;
708
709 ssim360 += (sample_ssim360 * weight);
710 sum_weight += weight;
711 }
712
713 return ssim360 / sum_weight;
714 }
715
716 static void compute_bilinear_map(SampleParams *p, BilinearMap *m, float x, float y)
717 {
718 float fixed_point_scale = (float)(1 << FIXED_POINT_PRECISION);
719
720 // All operations in here will fit in the 22 bit mantissa of floating point,
721 // since the fixed point precision is well under 22 bits
722 float x_image = av_clipf(x * p->x_image_range, 0, p->x_image_range) + p->x_image_offset;
723 float y_image = av_clipf(y * p->y_image_range, 0, p->y_image_range) + p->y_image_offset;
724
725 int x_floor = x_image;
726 int y_floor = y_image;
727 float x_diff = x_image - x_floor;
728 float y_diff = y_image - y_floor;
729
730 int x_ceil = x_floor + (x_diff > 1e-6);
731 int y_ceil = y_floor + (y_diff > 1e-6);
732 float x_inv_diff = 1.0f - x_diff;
733 float y_inv_diff = 1.0f - y_diff;
734
735 // Indices of the 4 samples from source frame
736 m->tli = x_floor + y_floor * p->stride;
737 m->tri = x_ceil + y_floor * p->stride;
738 m->bli = x_floor + y_ceil * p->stride;
739 m->bri = x_ceil + y_ceil * p->stride;
740
741 // Scale to be applied to each of the 4 samples from source frame
742 m->tlf = x_inv_diff * y_inv_diff * fixed_point_scale;
743 m->trf = x_diff * y_inv_diff * fixed_point_scale;
744 m->blf = x_inv_diff * y_diff * fixed_point_scale;
745 m->brf = x_diff * y_diff * fixed_point_scale;
746 }
747
748 static void get_equirect_map(float phi, float theta, float *x, float *y)
749 {
750 *x = 0.5f + theta / (2.0f * M_PI_F);
751 // y increases downwards
752 *y = 0.5f - phi / M_PI_F;
753 }
754
755 static void get_barrel_map(float phi, float theta, float *x, float *y)
756 {
757 float abs_phi = FFABS(phi);
758
759 if (abs_phi <= M_PI_4_F) {
760 // Equirect region
761 *x = 0.8f * (0.5f + theta / BARREL_THETA_RANGE);
762 // y increases downwards
763 *y = 0.5f - phi / BARREL_PHI_RANGE;
764 } else {
765 // Radial ratio on a unit circle = cot(abs_phi) / (expansion_cefficient).
766 // Using cos(abs_phi)/sin(abs_phi) explicitly to avoid division by zero
767 float radial_ratio = cosf(abs_phi) / (sinf(abs_phi) * DEFAULT_EXPANSION_COEF);
768 float circle_x = radial_ratio * sinf(theta);
769 float circle_y = radial_ratio * cosf(theta);
770 float offset_y = 0.25f;
771 if (phi < 0) {
772 // Bottom circle: theta increases clockwise, and front is upward
773 circle_y *= -1.0f;
774 offset_y += 0.5f;
775 }
776
777 *x = 0.8f + 0.1f * (1.0f + circle_x);
778 *y = offset_y + 0.25f * circle_y;
779 }
780 }
781
782 static void get_barrel_split_map(float phi, float theta, float expand_coef, float *x, float *y)
783 {
784 float abs_phi = FFABS(phi);
785
786 // Front Face [-PI/2, PI/2] -> [0,1].
787 // Back Face [PI/2, PI] and [-PI, -PI/2] -> [1, 2]
788 float radian_pi_theta = theta / M_PI_F + 0.5f;
789 int vFace;
790
791 if (radian_pi_theta < 0.0f)
792 radian_pi_theta += 2.0f;
793
794 // Front face at top (= 0), back face at bottom (= 1).
795 vFace = radian_pi_theta >= 1.0f;
796
797 if (abs_phi <= M_PI_4_F) {
798 // Equirect region
799 *x = 2.0f / 3.0f * (0.5f + (radian_pi_theta - vFace - 0.5f) / expand_coef);
800 // y increases downwards
801 *y = 0.25f + 0.5f * vFace - phi / (M_PI_F * expand_coef);
802 } else {
803 // Radial ratio on a unit circle = cot(abs_phi) / (expansion_cefficient).
804 // Using cos(abs_phi)/sin(abs_phi) explicitly to avoid division by zero
805 float radial_ratio = cosf(abs_phi) / (sinf(abs_phi) * expand_coef);
806 float circle_x = radial_ratio * sinf(theta);
807 float circle_y = radial_ratio * cosf(theta);
808 float offset_y = 0.25f;
809
810 if (vFace == 1) {
811 // Back Face: Flip
812 circle_x *= -1.0f;
813 circle_y = (circle_y >= 0.0f) ? (1 - circle_y) : (-1 - circle_y);
814 offset_y += 0.5f;
815
816 // Bottom circle: theta increases clockwise
817 if (phi < 0)
818 circle_y *= -1.0f;
819 } else {
820 // Front Face
821 // Bottom circle: theta increases clockwise
822 if (phi < 0)
823 circle_y *= -1.0f;
824 }
825
826 *x = 2.0f / 3.0f + 0.5f / 3.0f * (1.0f + circle_x);
827 *y = offset_y + 0.25f * circle_y / expand_coef; // y direction of expand_coeff (margin)
828 }
829 }
830
831 // Returns cube face, and provided face_x & face_y will range from [0, 1]
832 static int get_cubemap_face_map(float axis_vec_x, float axis_vec_y, float axis_vec_z, float *face_x, float *face_y)
833 {
834 // To check if phi, theta hits the top / bottom faces, we check the hit point of
835 // the axis vector on planes y = 1 and y = -1, and see if x & z are within [-1, 1]
836
837 // 0.577 < 1 / sqrt(3), which is less than the smallest sin(phi) falling on top/bottom faces
838 // This angle check will save computation from unnecessarily checking the top/bottom faces
839 if (FFABS(axis_vec_y) > 0.577f) {
840 float x_hit = axis_vec_x / FFABS(axis_vec_y);
841 float z_hit = axis_vec_z / axis_vec_y;
842
843 if (FFABS(x_hit) <= 1.f && FFABS(z_hit) <= 1.f) {
844 *face_x = x_hit;
845 // y increases downwards
846 *face_y = z_hit;
847 return axis_vec_y > 0 ? TOP : BOTTOM;
848 }
849 }
850
851 // Check for left / right faces
852 if (FFABS(axis_vec_x) > 0.577f) {
853 float z_hit = -axis_vec_z / axis_vec_x;
854 float y_hit = axis_vec_y / FFABS(axis_vec_x);
855
856 if (FFABS(z_hit) <= 1.f && FFABS(y_hit) <= 1.f) {
857 *face_x = z_hit;
858 // y increases downwards
859 *face_y = -y_hit;
860 return axis_vec_x > 0 ? RIGHT : LEFT;
861 }
862 }
863
864 // Front / back faces
865 *face_x = axis_vec_x / axis_vec_z;
866 // y increases downwards
867 *face_y = -axis_vec_y / FFABS(axis_vec_z);
868
869 return axis_vec_z > 0 ? FRONT : BACK;
870 }
871
872 static void get_cubemap32_map(float phi, float theta, float *x, float *y)
873 {
874 // face_projection_map maps each cube face to an index representing the face on the projection
875 // The indices 0->5 for cubemap 32 goes as:
876 // [0, 1, 2] as row 1, left to right
877 // [3, 4, 5] as row 2, left to right
878 static const int face_projection_map[] = {
879 [RIGHT] = 0, [LEFT] = 1, [TOP] = 2,
880 [BOTTOM] = 3, [FRONT] = 4, [BACK] = 5,
881 };
882
883 float axis_vec_x = cosf(phi) * sinf(theta);
884 float axis_vec_y = sinf(phi);
885 float axis_vec_z = cosf(phi) * cosf(theta);
886 float face_x = 0, face_y = 0;
887 int face_index = get_cubemap_face_map(axis_vec_x, axis_vec_y, axis_vec_z, &face_x, &face_y);
888
889 float x_offset = 1.f / 3.f * (face_projection_map[face_index] % 3);
890 float y_offset = .5f * (face_projection_map[face_index] / 3);
891
892 *x = x_offset + (face_x / DEFAULT_EXPANSION_COEF + 1.f) / 6.f;
893 *y = y_offset + (face_y / DEFAULT_EXPANSION_COEF + 1.f) / 4.f;
894 }
895
896 static void get_rotated_cubemap_map(float phi, float theta, float expand_coef, float *x, float *y)
897 {
898 // face_projection_map maps each cube face to an index representing the face on the projection
899 // The indices 0->5 for rotated cubemap goes as:
900 // [0, 1] as row 1, left to right
901 // [2, 3] as row 2, left to right
902 // [4, 5] as row 3, left to right
903 static const int face_projection_map[] = {
904 [LEFT] = 0, [TOP] = 1,
905 [FRONT] = 2, [BACK] = 3,
906 [RIGHT] = 4, [BOTTOM] = 5,
907 };
908
909 float axis_yaw_vec_x, axis_yaw_vec_y, axis_yaw_vec_z;
910 float axis_pitch_vec_z, axis_pitch_vec_y;
911 float x_offset, y_offset;
912 float face_x = 0, face_y = 0;
913 int face_index;
914
915 // Unrotate the cube and fix the face map:
916 // First undo the 45 degree yaw
917 theta += M_PI_4_F;
918
919 // Now we are looking at the middle of an edge. So convert to axis vector & undo the pitch
920 axis_yaw_vec_x = cosf(phi) * sinf(theta);
921 axis_yaw_vec_y = sinf(phi);
922 axis_yaw_vec_z = cosf(phi) * cosf(theta);
923
924 // The pitch axis is along +x, and has value of -45 degree. So, only y and z components change
925 axis_pitch_vec_z = (axis_yaw_vec_z - axis_yaw_vec_y) / M_SQRT2_F;
926 axis_pitch_vec_y = (axis_yaw_vec_y + axis_yaw_vec_z) / M_SQRT2_F;
927
928 face_index = get_cubemap_face_map(axis_yaw_vec_x, axis_pitch_vec_y, axis_pitch_vec_z, &face_x, &face_y);
929
930 // Correct for the orientation of the axes on the faces
931 if (face_index == LEFT || face_index == FRONT || face_index == RIGHT) {
932 // x increases downwards & y increases towards left
933 float upright_y = face_y;
934 face_y = face_x;
935 face_x = -upright_y;
936 } else if (face_index == TOP || face_index == BOTTOM) {
937 // turn the face upside-down for top and bottom
938 face_x *= -1.f;
939 face_y *= -1.f;
940 }
941
942 x_offset = .5f * (face_projection_map[face_index] & 1);
943 y_offset = 1.f / 3.f * (face_projection_map[face_index] >> 1);
944
945 *x = x_offset + (face_x / expand_coef + 1.f) / 4.f;
946 *y = y_offset + (face_y / expand_coef + 1.f) / 6.f;
947 }
948
949 static void get_projected_map(float phi, float theta, SampleParams *p, BilinearMap *m)
950 {
951 float x = 0, y = 0;
952 switch(p->projection) {
953 // TODO: Calculate for CDS
954 case PROJECTION_CUBEMAP23:
955 get_rotated_cubemap_map(phi, theta, p->expand_coef, &x, &y);
956 break;
957 case PROJECTION_CUBEMAP32:
958 get_cubemap32_map(phi, theta, &x, &y);
959 break;
960 case PROJECTION_BARREL:
961 get_barrel_map(phi, theta, &x, &y);
962 break;
963 case PROJECTION_BARREL_SPLIT:
964 get_barrel_split_map(phi, theta, p->expand_coef, &x, &y);
965 break;
966 // Assume PROJECTION_EQUIRECT as the default
967 case PROJECTION_EQUIRECT:
968 default:
969 get_equirect_map(phi, theta, &x, &y);
970 break;
971 }
972 compute_bilinear_map(p, m, x, y);
973 }
974
975 static int tape_supports_projection(int projection)
976 {
977 switch(projection) {
978 case PROJECTION_CUBEMAP23:
979 case PROJECTION_CUBEMAP32:
980 case PROJECTION_BARREL:
981 case PROJECTION_BARREL_SPLIT:
982 case PROJECTION_EQUIRECT:
983 return 1;
984 default:
985 return 0;
986 }
987 }
988
989 static float get_tape_angular_resolution(int projection, float expand_coef, int image_width, int image_height)
990 {
991 // NOTE: The angular resolution of a projected sphere is defined as
992 // the maximum possible horizontal angle of a pixel on the equator.
993 // We apply an intentional bias to the horizon as opposed to the meridian,
994 // since the view direction of most content is rarely closer to the poles
995
996 switch(projection) {
997 // TODO: Calculate for CDS
998 case PROJECTION_CUBEMAP23:
999 // Approximating atanf(pixel_width / (half_edge_width * sqrt2)) = pixel_width / (half_face_width * sqrt2)
1000 return expand_coef / (M_SQRT2_F * image_width / 4.f);
1001 case PROJECTION_CUBEMAP32:
1002 // Approximating atanf(pixel_width / half_face_width) = pixel_width / half_face_width
1003 return DEFAULT_EXPANSION_COEF / (image_width / 6.f);
1004 case PROJECTION_BARREL:
1005 return FFMAX(BARREL_THETA_RANGE / (0.8f * image_width), BARREL_PHI_RANGE / image_height);
1006 case PROJECTION_BARREL_SPLIT:
1007 return FFMAX((expand_coef * M_PI_F) / (2.0f / 3.0f * image_width),
1008 expand_coef * M_PI_2_F / (image_height / 2.0f));
1009 // Assume PROJECTION_EQUIRECT as the default
1010 case PROJECTION_EQUIRECT:
1011 default:
1012 return FFMAX(2.0f * M_PI_F / image_width, M_PI_F / image_height);
1013 }
1014 }
1015
1016 static int
1017 generate_eye_tape_map(SSIM360Context *s,
1018 int plane, int eye,
1019 SampleParams *ref_sample_params,
1020 SampleParams *main_sample_params)
1021 {
1022 int ref_image_width = ref_sample_params->x_image_range + 1;
1023 int ref_image_height = ref_sample_params->y_image_range + 1;
1024
1025 float angular_resolution =
1026 get_tape_angular_resolution(s->ref_projection, 1.f + s->ref_pad,
1027 ref_image_width, ref_image_height);
1028
1029 float conversion_factor = M_PI_2_F / (angular_resolution * angular_resolution);
1030 float start_phi = -M_PI_2_F + 4.0f * angular_resolution;
1031 float start_x = conversion_factor * sinf(start_phi);
1032 float end_phi = M_PI_2_F - 3.0f * angular_resolution;
1033 float end_x = conversion_factor * sinf(end_phi);
1034 float x_range = end_x - start_x;
1035
1036 // Ensure tape length is a multiple of 4, for full SSIM block coverage
1037 int tape_length = s->tape_length[plane] = ((int)ROUNDED_DIV(x_range, 4)) << 2;
1038
1039 s->ref_tape_map[plane][eye] = av_malloc_array(tape_length * 8, sizeof(BilinearMap));
1040 s->main_tape_map[plane][eye] = av_malloc_array(tape_length * 8, sizeof(BilinearMap));
1041 if (!s->ref_tape_map[plane][eye] || !s->main_tape_map[plane][eye])
1042 return AVERROR(ENOMEM);
1043
1044 s->angular_resolution[plane][eye] = angular_resolution;
1045
1046 // For easy memory access, we navigate the tape lengthwise on y
1047 for (int y_index = 0; y_index < tape_length; y_index ++) {
1048 int y_stride = y_index << 3;
1049
1050 float x = start_x + x_range * (y_index / (tape_length - 1.0f));
1051 // phi will be in range [-pi/2, pi/2]
1052 float mid_phi = asinf(x / conversion_factor);
1053
1054 float theta = mid_phi * M_PI_2_F / angular_resolution;
1055 theta = get_radius_between_negative_and_positive_pi(theta);
1056
1057 for (int x_index = 0; x_index < 8; x_index ++) {
1058 float phi = mid_phi + angular_resolution * (3.0f - x_index);
1059 int tape_index = y_stride + x_index;
1060 get_projected_map(phi, theta, ref_sample_params, &s->ref_tape_map [plane][eye][tape_index]);
1061 get_projected_map(phi, theta, main_sample_params, &s->main_tape_map[plane][eye][tape_index]);
1062 }
1063 }
1064
1065 return 0;
1066 }
1067
1068 static int generate_tape_maps(SSIM360Context *s, AVFrame *main, const AVFrame *ref)
1069 {
1070 // A tape is a long segment with 8 pixels thickness, with the angular center at the middle (below 4th pixel).
1071 // When it takes a full loop around a sphere, it will overlap the starting point at half the width from above.
1072 int ref_stereo_format = s->ref_stereo_format;
1073 int main_stereo_format = s->main_stereo_format;
1074 int are_both_stereo = (main_stereo_format != STEREO_FORMAT_MONO) && (ref_stereo_format != STEREO_FORMAT_MONO);
1075 int min_eye_count = 1 + are_both_stereo;
1076 int ret;
1077
1078 for (int i = 0; i < s->nb_components; i ++) {
1079 int ref_width = s->ref_planewidth[i];
1080 int ref_height = s->ref_planeheight[i];
1081 int main_width = s->main_planewidth[i];
1082 int main_height = s->main_planeheight[i];
1083
1084 int is_ref_LR = (ref_stereo_format == STEREO_FORMAT_LR);
1085 int is_ref_TB = (ref_stereo_format == STEREO_FORMAT_TB);
1086 int is_main_LR = (main_stereo_format == STEREO_FORMAT_LR);
1087 int is_main_TB = (main_stereo_format == STEREO_FORMAT_TB);
1088
1089 int ref_image_width = is_ref_LR ? ref_width >> 1 : ref_width;
1090 int ref_image_height = is_ref_TB ? ref_height >> 1 : ref_height;
1091 int main_image_width = is_main_LR ? main_width >> 1 : main_width;
1092 int main_image_height = is_main_TB ? main_height >> 1 : main_height;
1093
1094 for (int eye = 0; eye < min_eye_count; eye ++) {
1095 SampleParams ref_sample_params = {
1096 .stride = ref->linesize[i],
1097 .planewidth = ref_width,
1098 .planeheight = ref_height,
1099 .x_image_range = ref_image_width - 1,
1100 .y_image_range = ref_image_height - 1,
1101 .x_image_offset = is_ref_LR * eye * ref_image_width,
1102 .y_image_offset = is_ref_TB * eye * ref_image_height,
1103 .projection = s->ref_projection,
1104 .expand_coef = 1.f + s->ref_pad,
1105 };
1106
1107 SampleParams main_sample_params = {
1108 .stride = main->linesize[i],
1109 .planewidth = main_width,
1110 .planeheight = main_height,
1111 .x_image_range = main_image_width - 1,
1112 .y_image_range = main_image_height - 1,
1113 .x_image_offset = is_main_LR * eye * main_image_width,
1114 .y_image_offset = is_main_TB * eye * main_image_height,
1115 .projection = s->main_projection,
1116 .expand_coef = 1.f + s->main_pad,
1117 };
1118
1119 ret = generate_eye_tape_map(s, i, eye, &ref_sample_params, &main_sample_params);
1120 if (ret < 0)
1121 return ret;
1122 }
1123 }
1124
1125 return 0;
1126 }
1127
1128 static int do_ssim360(FFFrameSync *fs)
1129 {
1130 AVFilterContext *ctx = fs->parent;
1131 SSIM360Context *s = ctx->priv;
1132 AVFrame *master, *ref;
1133 AVDictionary **metadata;
1134 double c[4], ssim360v = 0.0, ssim360p50 = 0.0;
1135 int ret;
1136 int need_frame_skip = s->nb_net_frames % (s->frame_skip_ratio + 1);
1137 HeatmapList* h_ptr = NULL;
1138
1139 ret = ff_framesync_dualinput_get(fs, &master, &ref);
1140 if (ret < 0)
1141 return ret;
1142
1143 s->nb_net_frames++;
1144
1145 if (need_frame_skip)
1146 return ff_filter_frame(ctx->outputs[0], master);
1147
1148 metadata = &master->metadata;
1149
1150 if (s->use_tape && !s->tape_length[0]) {
1151 ret = generate_tape_maps(s, master, ref);
1152 if (ret < 0)
1153 return ret;
1154 }
1155
1156 for (int i = 0; i < s->nb_components; i++) {
1157 if (s->use_tape) {
1158 c[i] = ssim360_tape(master->data[i], s->main_tape_map[i][0],
1159 ref->data[i], s->ref_tape_map [i][0],
1160 s->tape_length[i], s->max, s->temp,
1161 s->ssim360_hist[i], &s->ssim360_hist_net[i],
1162 s->angular_resolution[i][0], s->heatmaps);
1163
1164 if (s->ref_tape_map[i][1]) {
1165 c[i] += ssim360_tape(master->data[i], s->main_tape_map[i][1],
1166 ref->data[i], s->ref_tape_map[i][1],
1167 s->tape_length[i], s->max, s->temp,
1168 s->ssim360_hist[i], &s->ssim360_hist_net[i],
1169 s->angular_resolution[i][1], s->heatmaps);
1170 c[i] /= 2.f;
1171 }
1172 } else {
1173 c[i] = s->ssim360_plane(master->data[i], master->linesize[i],
1174 ref->data[i], ref->linesize[i],
1175 s->ref_planewidth[i], s->ref_planeheight[i],
1176 s->temp, s->max, s->density);
1177 }
1178
1179 s->ssim360[i] += c[i];
1180 ssim360v += s->coefs[i] * c[i];
1181 }
1182
1183 s->nb_ssim_frames++;
1184 if (s->heatmaps) {
1185 map_uninit(&s->heatmaps->map);
1186 h_ptr = s->heatmaps;
1187 s->heatmaps = s->heatmaps->next;
1188 av_freep(&h_ptr);
1189 }
1190 s->ssim360_total += ssim360v;
1191
1192 // Record percentiles from histogram and attach metadata when using tape
1193 if (s->use_tape) {
1194 int hist_indices[4];
1195 double hist_weight[4];
1196
1197 for (int i = 0; i < s->nb_components; i++) {
1198 hist_indices[i] = SSIM360_HIST_SIZE - 1;
1199 hist_weight[i] = 0;
1200 }
1201
1202 for (int p = 0; PERCENTILE_LIST[p] >= 0.0; p ++) {
1203 for (int i = 0; i < s->nb_components; i++) {
1204 double target_weight, ssim360p;
1205
1206 // Target weight = total number of samples above the specified percentile
1207 target_weight = (1. - PERCENTILE_LIST[p]) * s->ssim360_hist_net[i];
1208 target_weight = FFMAX(target_weight, 1);
1209 while(hist_indices[i] >= 0 && hist_weight[i] < target_weight) {
1210 hist_weight[i] += s->ssim360_hist[i][hist_indices[i]];
1211 hist_indices[i] --;
1212 }
1213
1214 ssim360p = (double)(hist_indices[i] + 1) / (double)(SSIM360_HIST_SIZE - 1);
1215 if (PERCENTILE_LIST[p] == 0.5)
1216 ssim360p50 += s->coefs[i] * ssim360p;
1217 s->ssim360_percentile_sum[i][p] += ssim360p;
1218 }
1219 }
1220
1221 for (int i = 0; i < s->nb_components; i++) {
1222 memset(s->ssim360_hist[i], 0, SSIM360_HIST_SIZE * sizeof(double));
1223 s->ssim360_hist_net[i] = 0;
1224 }
1225
1226 for (int i = 0; i < s->nb_components; i++) {
1227 int cidx = s->is_rgb ? s->rgba_map[i] : i;
1228 set_meta(metadata, "lavfi.ssim360.", s->comps[i], c[cidx]);
1229 }
1230
1231 // Use p50 as the aggregated value
1232 set_meta(metadata, "lavfi.ssim360.All", 0, ssim360p50);
1233 set_meta(metadata, "lavfi.ssim360.dB", 0, ssim360_db(ssim360p50, 1.0));
1234
1235 if (s->stats_file) {
1236 fprintf(s->stats_file, "n:%"PRId64" ", s->nb_ssim_frames);
1237
1238 for (int i = 0; i < s->nb_components; i++) {
1239 int cidx = s->is_rgb ? s->rgba_map[i] : i;
1240 fprintf(s->stats_file, "%c:%f ", s->comps[i], c[cidx]);
1241 }
1242
1243 fprintf(s->stats_file, "All:%f (%f)\n", ssim360p50, ssim360_db(ssim360p50, 1.0));
1244 }
1245 }
1246
1247 return ff_filter_frame(ctx->outputs[0], master);
1248 }
1249
1250 static int parse_heatmaps(void *logctx, HeatmapList **proot,
1251 const char *data, int w, int h)
1252 {
1253 HeatmapList *root = NULL;
1254 HeatmapList **next = &root;
1255
1256 int ret;
1257
1258 // skip video id line
1259 data = strchr(data, '\n');
1260 if (!data) {
1261 av_log(logctx, AV_LOG_ERROR, "Invalid heatmap syntax\n");
1262 return AVERROR(EINVAL);
1263 }
1264 data++;
1265
1266 while (*data) {
1267 HeatmapList *cur;
1268 char *line = av_get_token(&data, "\n");
1269 char *saveptr, *val;
1270 int i;
1271
1272 if (!line) {
1273 ret = AVERROR(ENOMEM);
1274 goto fail;
1275 }
1276
1277 // first value is frame id
1278 av_strtok(line, ",", &saveptr);
1279
1280 ret = map_alloc(next, w, h);
1281 if (ret < 0)
1282 goto line_fail;
1283
1284 cur = *next;
1285 next = &cur->next;
1286
1287 i = 0;
1288 while ((val = av_strtok(NULL, ",", &saveptr))) {
1289 if (i >= w * h) {
1290 av_log(logctx, AV_LOG_ERROR, "Too many entries in a heat map\n");
1291 ret = AVERROR(EINVAL);
1292 goto line_fail;
1293 }
1294
1295 cur->map.value[i++] = atof(val);
1296 }
1297
1298 line_fail:
1299 av_freep(&line);
1300 if (ret < 0)
1301 goto fail;
1302 }
1303
1304 *proot = root;
1305
1306 return 0;
1307 fail:
1308 map_list_free(&root);
1309 return ret;
1310 }
1311
1312 static av_cold int init(AVFilterContext *ctx)
1313 {
1314 SSIM360Context *s = ctx->priv;
1315 int err;
1316
1317 if (s->stats_file_str) {
1318 if (!strcmp(s->stats_file_str, "-")) {
1319 s->stats_file = stdout;
1320 } else {
1321 s->stats_file = avpriv_fopen_utf8(s->stats_file_str, "w");
1322 if (!s->stats_file) {
1323 err = AVERROR(errno);
1324 av_log(ctx, AV_LOG_ERROR, "Could not open stats file %s: %s\n",
1325 s->stats_file_str, av_err2str(err));
1326 return err;
1327 }
1328 }
1329 }
1330
1331 if (s->use_tape && s->heatmap_str) {
1332 err = parse_heatmaps(ctx, &s->heatmaps, s->heatmap_str,
1333 s->default_heatmap_w, s->default_heatmap_h);
1334 if (err < 0)
1335 return err;
1336 }
1337
1338 s->fs.on_event = do_ssim360;
1339 return 0;
1340 }
1341
1342 static int config_input_main(AVFilterLink *inlink)
1343 {
1344 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
1345 AVFilterContext *ctx = inlink->dst;
1346 SSIM360Context *s = ctx->priv;
1347
1348 s->main_planeheight[0] = inlink->h;
1349 s->main_planeheight[3] = inlink->h;
1350 s->main_planeheight[1] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
1351 s->main_planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
1352
1353 s->main_planewidth[0] = inlink->w;
1354 s->main_planewidth[3] = inlink->w;
1355 s->main_planewidth[1] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
1356 s->main_planewidth[2] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
1357
1358 // If main projection is unindentified, assume it is same as reference
1359 if (s->main_projection == PROJECTION_N)
1360 s->main_projection = s->ref_projection;
1361
1362 // If main stereo format is unindentified, assume it is same as reference
1363 if (s->main_stereo_format == STEREO_FORMAT_N)
1364 s->main_stereo_format = s->ref_stereo_format;
1365
1366 return 0;
1367 }
1368
1369 static int generate_density_map(SSIM360Context *s, int w, int h)
1370 {
1371 double d, r_square, cos_square;
1372 int ow, oh, ret;
1373
1374 ret = map_init(&s->density, w, h);
1375 if (ret < 0)
1376 return ret;
1377
1378 switch (s->ref_stereo_format) {
1379 case STEREO_FORMAT_TB:
1380 h >>= 1;
1381 break;
1382 case STEREO_FORMAT_LR:
1383 w >>= 1;
1384 break;
1385 }
1386
1387 switch (s->ref_projection) {
1388 case PROJECTION_EQUIRECT:
1389 for (int i = 0; i < h; i++) {
1390 d = cos(((0.5 + i) / h - 0.5) * M_PI);
1391 for (int j = 0; j < w; j++)
1392 s->density.value[i * w + j] = d;
1393 }
1394 break;
1395 case PROJECTION_CUBEMAP32:
1396 // for one quater of a face
1397 for (int i = 0; i < h / 4; i++) {
1398 for (int j = 0; j < w / 6; j++) {
1399 // r = normalized distance to the face center
1400 r_square =
1401 (0.5 + i) / (h / 2) * (0.5 + i) / (h / 2) +
1402 (0.5 + j) / (w / 3) * (0.5 + j) / (w / 3);
1403 r_square /= DEFAULT_EXPANSION_COEF * DEFAULT_EXPANSION_COEF;
1404 cos_square = 0.25 / (r_square + 0.25);
1405 d = pow(cos_square, 1.5);
1406
1407 for (int face = 0; face < 6; face++) {
1408 // center of a face
1409 switch (face) {
1410 case 0:
1411 oh = h / 4;
1412 ow = w / 6;
1413 break;
1414 case 1:
1415 oh = h / 4;
1416 ow = w / 6 + w / 3;
1417 break;
1418 case 2:
1419 oh = h / 4;
1420 ow = w / 6 + 2 * w / 3;
1421 break;
1422 case 3:
1423 oh = h / 4 + h / 2;
1424 ow = w / 6;
1425 break;
1426 case 4:
1427 oh = h / 4 + h / 2;
1428 ow = w / 6 + w / 3;
1429 break;
1430 case 5:
1431 oh = h / 4 + h / 2;
1432 ow = w / 6 + 2 * w / 3;
1433 break;
1434 }
1435 s->density.value[(oh - 1 - i) * w + ow - 1 - j] = d;
1436 s->density.value[(oh - 1 - i) * w + ow + j] = d;
1437 s->density.value[(oh + i) * w + ow - 1 - j] = d;
1438 s->density.value[(oh + i) * w + ow + j] = d;
1439 }
1440 }
1441 }
1442 break;
1443 case PROJECTION_CUBEMAP23:
1444 // for one quater of a face
1445 for (int i = 0; i < h / 6; i++) {
1446 for (int j = 0; j < w / 4; j++) {
1447 // r = normalized distance to the face center
1448 r_square =
1449 (0.5 + i) / (h / 3) * (0.5 + i) / (h / 3) +
1450 (0.5 + j) / (w / 2) * (0.5 + j) / (w / 2);
1451 r_square /= (1.f + s->ref_pad) * (1.f + s->ref_pad);
1452 cos_square = 0.25 / (r_square + 0.25);
1453 d = pow(cos_square, 1.5);
1454
1455 for (int face = 0; face < 6; face++) {
1456 // center of a face
1457 switch (face) {
1458 case 0:
1459 ow = w / 4;
1460 oh = h / 6;
1461 break;
1462 case 1:
1463 ow = w / 4;
1464 oh = h / 6 + h / 3;
1465 break;
1466 case 2:
1467 ow = w / 4;
1468 oh = h / 6 + 2 * h / 3;
1469 break;
1470 case 3:
1471 ow = w / 4 + w / 2;
1472 oh = h / 6;
1473 break;
1474 case 4:
1475 ow = w / 4 + w / 2;
1476 oh = h / 6 + h / 3;
1477 break;
1478 case 5:
1479 ow = w / 4 + w / 2;
1480 oh = h / 6 + 2 * h / 3;
1481 break;
1482 }
1483 s->density.value[(oh - 1 - i) * w + ow - 1 - j] = d;
1484 s->density.value[(oh - 1 - i) * w + ow + j] = d;
1485 s->density.value[(oh + i) * w + ow - 1 - j] = d;
1486 s->density.value[(oh + i) * w + ow + j] = d;
1487 }
1488 }
1489 }
1490 break;
1491 case PROJECTION_BARREL:
1492 // side face
1493 for (int i = 0; i < h; i++) {
1494 for (int j = 0; j < w * 4 / 5; j++) {
1495 d = cos(((0.5 + i) / h - 0.5) * DEFAULT_EXPANSION_COEF * M_PI_2);
1496 s->density.value[i * w + j] = d * d * d;
1497 }
1498 }
1499 // top and bottom
1500 for (int i = 0; i < h; i++) {
1501 for (int j = w * 4 / 5; j < w; j++) {
1502 double dx = DEFAULT_EXPANSION_COEF * (0.5 + j - w * 0.90) / (w * 0.10);
1503 double dx_squared = dx * dx;
1504
1505 double top_dy = DEFAULT_EXPANSION_COEF * (0.5 + i - h * 0.25) / (h * 0.25);
1506 double top_dy_squared = top_dy * top_dy;
1507
1508 double bottom_dy = DEFAULT_EXPANSION_COEF * (0.5 + i - h * 0.75) / (h * 0.25);
1509 double bottom_dy_squared = bottom_dy * bottom_dy;
1510
1511 // normalized distance to the circle center
1512 r_square = (i < h / 2 ? top_dy_squared : bottom_dy_squared) + dx_squared;
1513 if (r_square > 1.0)
1514 continue;
1515
1516 cos_square = 1.0 / (r_square + 1.0);
1517 d = pow(cos_square, 1.5);
1518 s->density.value[i * w + j] = d;
1519 }
1520 }
1521 break;
1522 default:
1523 // TODO: SSIM360_v1
1524 for (int i = 0; i < h; i++) {
1525 for (int j = 0; j < w; j++)
1526 s->density.value[i * w + j] = 0;
1527 }
1528 }
1529
1530 switch (s->ref_stereo_format) {
1531 case STEREO_FORMAT_TB:
1532 for (int i = 0; i < h; i++) {
1533 for (int j = 0; j < w; j++)
1534 s->density.value[(i + h) * w + j] = s->density.value[i * w + j];
1535 }
1536 break;
1537 case STEREO_FORMAT_LR:
1538 for (int i = 0; i < h; i++) {
1539 for (int j = 0; j < w; j++)
1540 s->density.value[i * w + j + w] = s->density.value[i * w + j];
1541 }
1542 }
1543
1544 return 0;
1545 }
1546
1547 static int config_input_ref(AVFilterLink *inlink)
1548 {
1549 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
1550 AVFilterContext *ctx = inlink->dst;
1551 SSIM360Context *s = ctx->priv;
1552 int sum = 0;
1553
1554 s->nb_components = desc->nb_components;
1555
1556 s->ref_planeheight[0] = inlink->h;
1557 s->ref_planeheight[3] = inlink->h;
1558 s->ref_planeheight[1] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
1559 s->ref_planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
1560
1561 s->ref_planewidth[0] = inlink->w;
1562 s->ref_planewidth[3] = inlink->w;
1563 s->ref_planewidth[1] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
1564 s->ref_planewidth[2] = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
1565
1566 s->is_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
1567 s->comps[0] = s->is_rgb ? 'R' : 'Y';
1568 s->comps[1] = s->is_rgb ? 'G' : 'U';
1569 s->comps[2] = s->is_rgb ? 'B' : 'V';
1570 s->comps[3] = 'A';
1571
1572 // If chroma computation is disabled, and the format is YUV, skip U & V channels
1573 if (!s->is_rgb && !s->compute_chroma)
1574 s->nb_components = 1;
1575
1576 s->max = (1 << desc->comp[0].depth) - 1;
1577
1578 s->ssim360_plane = desc->comp[0].depth > 8 ? ssim360_plane_16bit : ssim360_plane_8bit;
1579
1580 for (int i = 0; i < s->nb_components; i++)
1581 sum += s->ref_planeheight[i] * s->ref_planewidth[i];
1582 for (int i = 0; i < s->nb_components; i++)
1583 s->coefs[i] = (double) s->ref_planeheight[i] * s->ref_planewidth[i] / sum;
1584
1585 return 0;
1586 }
1587
1588 static int config_output(AVFilterLink *outlink)
1589 {
1590 AVFilterContext *ctx = outlink->src;
1591 SSIM360Context *s = ctx->priv;
1592 AVFilterLink *mainlink = ctx->inputs[0];
1593 AVFilterLink *reflink = ctx->inputs[0];
1594 FilterLink *il = ff_filter_link(mainlink);
1595 FilterLink *ol = ff_filter_link(outlink);
1596 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(outlink->format);
1597 int ret;
1598
1599 // Use tape algorithm if any of frame sizes, projections or stereo format are not equal
1600 if (ctx->inputs[0]->w != ctx->inputs[1]->w || ctx->inputs[0]->h != ctx->inputs[1]->h ||
1601 s->ref_projection != s->main_projection || s->ref_stereo_format != s->main_stereo_format)
1602 s->use_tape = 1;
1603
1604 // Finally, if we have decided to / forced to use tape, check if tape supports both input and output projection
1605 if (s->use_tape &&
1606 !(tape_supports_projection(s->main_projection) &&
1607 tape_supports_projection(s->ref_projection))) {
1608 av_log(ctx, AV_LOG_ERROR, "Projection is unsupported for the tape based algorithm\n");
1609 return AVERROR(EINVAL);
1610 }
1611
1612 if (s->use_tape) {
1613 // s->temp will be allocated for the tape width = 8. The tape is long downwards
1614 s->temp = av_malloc_array((2 * 8 + 12), sizeof(*s->temp));
1615 if (!s->temp)
1616 return AVERROR(ENOMEM);
1617
1618 memset(s->ssim360_percentile_sum, 0, sizeof(s->ssim360_percentile_sum));
1619
1620 for (int i = 0; i < s->nb_components; i++) {
1621 FF_ALLOCZ_TYPED_ARRAY(s->ssim360_hist[i], SSIM360_HIST_SIZE);
1622 if (!s->ssim360_hist[i])
1623 return AVERROR(ENOMEM);
1624 }
1625 } else {
1626 s->temp = av_malloc_array((2 * reflink->w + 12), sizeof(*s->temp) * (1 + (desc->comp[0].depth > 8)));
1627 if (!s->temp)
1628 return AVERROR(ENOMEM);
1629
1630 if (!s->density.value) {
1631 ret = generate_density_map(s, reflink->w, reflink->h);
1632 if (ret < 0)
1633 return ret;
1634 }
1635 }
1636
1637 ret = ff_framesync_init_dualinput(&s->fs, ctx);
1638 if (ret < 0)
1639 return ret;
1640
1641 outlink->w = mainlink->w;
1642 outlink->h = mainlink->h;
1643 outlink->time_base = mainlink->time_base;
1644 outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
1645 ol->frame_rate = il->frame_rate;
1646
1647 s->fs.opt_shortest = 1;
1648 s->fs.opt_repeatlast = 1;
1649
1650 ret = ff_framesync_configure(&s->fs);
1651 if (ret < 0)
1652 return ret;
1653
1654 return 0;
1655 }
1656
1657 static int activate(AVFilterContext *ctx)
1658 {
1659 SSIM360Context *s = ctx->priv;
1660 return ff_framesync_activate(&s->fs);
1661 }
1662
1663 static av_cold void uninit(AVFilterContext *ctx)
1664 {
1665 SSIM360Context *s = ctx->priv;
1666
1667 if (s->nb_ssim_frames > 0) {
1668 char buf[256];
1669 buf[0] = 0;
1670 // Log average SSIM360 values
1671 for (int i = 0; i < s->nb_components; i++) {
1672 int c = s->is_rgb ? s->rgba_map[i] : i;
1673 av_strlcatf(buf, sizeof(buf), " %c:%f (%f)", s->comps[i], s->ssim360[c] / s->nb_ssim_frames,
1674 ssim360_db(s->ssim360[c], s->nb_ssim_frames));
1675 }
1676 av_log(ctx, AV_LOG_INFO, "SSIM360%s All:%f (%f)\n", buf,
1677 s->ssim360_total / s->nb_ssim_frames, ssim360_db(s->ssim360_total, s->nb_ssim_frames));
1678
1679 // Log percentiles from histogram when using tape
1680 if (s->use_tape) {
1681 for (int p = 0; PERCENTILE_LIST[p] >= 0.0; p++) {
1682 buf[0] = 0;
1683 for (int i = 0; i < s->nb_components; i++) {
1684 int c = s->is_rgb ? s->rgba_map[i] : i;
1685 double ssim360p = s->ssim360_percentile_sum[i][p] / (double)(s->nb_ssim_frames);
1686 av_strlcatf(buf, sizeof(buf), " %c:%f (%f)", s->comps[c], ssim360p, ssim360_db(ssim360p, 1));
1687 }
1688 av_log(ctx, AV_LOG_INFO, "SSIM360_p%d%s\n", (int)(PERCENTILE_LIST[p] * 100.), buf);
1689 }
1690 }
1691 }
1692
1693 // free density map
1694 map_uninit(&s->density);
1695
1696 map_list_free(&s->heatmaps);
1697
1698 for (int i = 0; i < s->nb_components; i++) {
1699 for (int eye = 0; eye < 2; eye++) {
1700 av_freep(&s->ref_tape_map[i][eye]);
1701 av_freep(&s->main_tape_map[i][eye]);
1702 }
1703 av_freep(&s->ssim360_hist[i]);
1704 }
1705
1706 ff_framesync_uninit(&s->fs);
1707
1708 if (s->stats_file && s->stats_file != stdout)
1709 fclose(s->stats_file);
1710
1711 av_freep(&s->temp);
1712 }
1713
1714 #define PF(suf) AV_PIX_FMT_YUV420##suf, AV_PIX_FMT_YUV422##suf, AV_PIX_FMT_YUV444##suf, AV_PIX_FMT_GBR##suf
1715 static const enum AVPixelFormat ssim360_pixfmts[] = {
1716 AV_PIX_FMT_GRAY8,
1717 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P,
1718 AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
1719 AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
1720 AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ444P,
1721 AV_PIX_FMT_GBRP,
1722 PF(P9), PF(P10), PF(P12), PF(P14), PF(P16),
1723 AV_PIX_FMT_NONE
1724 };
1725 #undef PF
1726
1727 static const AVFilterPad ssim360_inputs[] = {
1728 {
1729 .name = "main",
1730 .type = AVMEDIA_TYPE_VIDEO,
1731 .config_props = config_input_main,
1732 },
1733 {
1734 .name = "reference",
1735 .type = AVMEDIA_TYPE_VIDEO,
1736 .config_props = config_input_ref,
1737 },
1738 };
1739
1740 static const AVFilterPad ssim360_outputs[] = {
1741 {
1742 .name = "default",
1743 .type = AVMEDIA_TYPE_VIDEO,
1744 .config_props = config_output,
1745 },
1746 };
1747
1748 const AVFilter ff_vf_ssim360 = {
1749 .name = "ssim360",
1750 .description = NULL_IF_CONFIG_SMALL("Calculate the SSIM between two 360 video streams."),
1751 .preinit = ssim360_framesync_preinit,
1752 .init = init,
1753 .uninit = uninit,
1754 .activate = activate,
1755 .priv_size = sizeof(SSIM360Context),
1756 .priv_class = &ssim360_class,
1757 FILTER_INPUTS(ssim360_inputs),
1758 FILTER_OUTPUTS(ssim360_outputs),
1759 FILTER_PIXFMTS_ARRAY(ssim360_pixfmts),
1760 };
1761