aboutsummaryrefslogtreecommitdiffstats
path: root/libavfilter/vf_ssim.c
blob: 4dcdc0548b11d8e7a36f129f1c234176a8da403d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
/*
 * Copyright (c) 2003-2013 Loren Merritt
 * Copyright (c) 2015 Paul B Mahol
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/* Computes the Structural Similarity Metric between two video streams.
 * original algorithm:
 * Z. Wang, A. C. Bovik, H. R. Sheikh and E. P. Simoncelli,
 *   "Image quality assessment: From error visibility to structural similarity,"
 *   IEEE Transactions on Image Processing, vol. 13, no. 4, pp. 600-612, Apr. 2004.
 *
 * To improve speed, this implementation uses the standard approximation of
 * overlapped 8x8 block sums, rather than the original gaussian weights.
 */

/*
 * @file
 * Caculate the SSIM between two input videos.
 */

#include "libavutil/avstring.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "drawutils.h"
#include "formats.h"
#include "framesync.h"
#include "internal.h"
#include "ssim.h"
#include "video.h"

typedef struct SSIMContext {
    const AVClass *class;
    FFFrameSync fs;
    FILE *stats_file;
    char *stats_file_str;
    int nb_components;
    int max;
    uint64_t nb_frames;
    double ssim[4], ssim_total;
    char comps[4];
    float coefs[4];
    uint8_t rgba_map[4];
    int planewidth[4];
    int planeheight[4];
    int *temp;
    int is_rgb;
    float (*ssim_plane)(SSIMDSPContext *dsp,
                        uint8_t *main, int main_stride,
                        uint8_t *ref, int ref_stride,
                        int width, int height, void *temp,
                        int max);
    SSIMDSPContext dsp;
} SSIMContext;

#define OFFSET(x) offsetof(SSIMContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM

static const AVOption ssim_options[] = {
    {"stats_file", "Set file where to store per-frame difference information", OFFSET(stats_file_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
    {"f",          "Set file where to store per-frame difference information", OFFSET(stats_file_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
    { NULL }
};

FRAMESYNC_DEFINE_CLASS(ssim, SSIMContext, fs);

static void set_meta(AVDictionary **metadata, const char *key, char comp, float d)
{
    char value[128];
    snprintf(value, sizeof(value), "%0.2f", d);
    if (comp) {
        char key2[128];
        snprintf(key2, sizeof(key2), "%s%c", key, comp);
        av_dict_set(metadata, key2, value, 0);
    } else {
        av_dict_set(metadata, key, value, 0);
    }
}

static void ssim_4x4xn_16bit(const uint8_t *main8, ptrdiff_t main_stride,
                             const uint8_t *ref8, ptrdiff_t ref_stride,
                             int64_t (*sums)[4], int width)
{
    const uint16_t *main16 = (const uint16_t *)main8;
    const uint16_t *ref16  = (const uint16_t *)ref8;
    int x, y, z;

    main_stride >>= 1;
    ref_stride >>= 1;

    for (z = 0; z < width; z++) {
        uint64_t s1 = 0, s2 = 0, ss = 0, s12 = 0;

        for (y = 0; y < 4; y++) {
            for (x = 0; x < 4; x++) {
                unsigned a = main16[x + y * main_stride];
                unsigned b = ref16[x + y * ref_stride];

                s1  += a;
                s2  += b;
                ss  += a*a;
                ss  += b*b;
                s12 += a*b;
            }
        }

        sums[z][0] = s1;
        sums[z][1] = s2;
        sums[z][2] = ss;
        sums[z][3] = s12;
        main16 += 4;
        ref16 += 4;
    }
}

static void ssim_4x4xn_8bit(const uint8_t *main, ptrdiff_t main_stride,
                            const uint8_t *ref, ptrdiff_t ref_stride,
                            int (*sums)[4], int width)
{
    int x, y, z;

    for (z = 0; z < width; z++) {
        uint32_t s1 = 0, s2 = 0, ss = 0, s12 = 0;

        for (y = 0; y < 4; y++) {
            for (x = 0; x < 4; x++) {
                int a = main[x + y * main_stride];
                int b = ref[x + y * ref_stride];

                s1  += a;
                s2  += b;
                ss  += a*a;
                ss  += b*b;
                s12 += a*b;
            }
        }

        sums[z][0] = s1;
        sums[z][1] = s2;
        sums[z][2] = ss;
        sums[z][3] = s12;
        main += 4;
        ref += 4;
    }
}

static float ssim_end1x(int64_t s1, int64_t s2, int64_t ss, int64_t s12, int max)
{
    int64_t ssim_c1 = (int64_t)(.01*.01*max*max*64 + .5);
    int64_t ssim_c2 = (int64_t)(.03*.03*max*max*64*63 + .5);

    int64_t fs1 = s1;
    int64_t fs2 = s2;
    int64_t fss = ss;
    int64_t fs12 = s12;
    int64_t vars = fss * 64 - fs1 * fs1 - fs2 * fs2;
    int64_t covar = fs12 * 64 - fs1 * fs2;

    return (float)(2 * fs1 * fs2 + ssim_c1) * (float)(2 * covar + ssim_c2)
         / ((float)(fs1 * fs1 + fs2 * fs2 + ssim_c1) * (float)(vars + ssim_c2));
}

static float ssim_end1(int s1, int s2, int ss, int s12)
{
    static const int ssim_c1 = (int)(.01*.01*255*255*64 + .5);
    static const int ssim_c2 = (int)(.03*.03*255*255*64*63 + .5);

    int fs1 = s1;
    int fs2 = s2;
    int fss = ss;
    int fs12 = s12;
    int vars = fss * 64 - fs1 * fs1 - fs2 * fs2;
    int covar = fs12 * 64 - fs1 * fs2;

    return (float)(2 * fs1 * fs2 + ssim_c1) * (float)(2 * covar + ssim_c2)
         / ((float)(fs1 * fs1 + fs2 * fs2 + ssim_c1) * (float)(vars + ssim_c2));
}

static float ssim_endn_16bit(const int64_t (*sum0)[4], const int64_t (*sum1)[4], int width, int max)
{
    float ssim = 0.0;
    int i;

    for (i = 0; i < width; i++)
        ssim += ssim_end1x(sum0[i][0] + sum0[i + 1][0] + sum1[i][0] + sum1[i + 1][0],
                           sum0[i][1] + sum0[i + 1][1] + sum1[i][1] + sum1[i + 1][1],
                           sum0[i][2] + sum0[i + 1][2] + sum1[i][2] + sum1[i + 1][2],
                           sum0[i][3] + sum0[i + 1][3] + sum1[i][3] + sum1[i + 1][3],
                           max);
    return ssim;
}

static float ssim_endn_8bit(const int (*sum0)[4], const int (*sum1)[4], int width)
{
    float ssim = 0.0;
    int i;

    for (i = 0; i < width; i++)
        ssim += ssim_end1(sum0[i][0] + sum0[i + 1][0] + sum1[i][0] + sum1[i + 1][0],
                          sum0[i][1] + sum0[i + 1][1] + sum1[i][1] + sum1[i + 1][1],
                          sum0[i][2] + sum0[i + 1][2] + sum1[i][2] + sum1[i + 1][2],
                          sum0[i][3] + sum0[i + 1][3] + sum1[i][3] + sum1[i + 1][3]);
    return ssim;
}

#define SUM_LEN(w) (((w) >> 2) + 3)

static float ssim_plane_16bit(SSIMDSPContext *dsp,
                              uint8_t *main, int main_stride,
                              uint8_t *ref, int ref_stride,
                              int width, int height, void *temp,
                              int max)
{
    int z = 0, y;
    float ssim = 0.0;
    int64_t (*sum0)[4] = temp;
    int64_t (*sum1)[4] = sum0 + SUM_LEN(width);

    width >>= 2;
    height >>= 2;

    for (y = 1; y < height; y++) {
        for (; z <= y; z++) {
            FFSWAP(void*, sum0, sum1);
            ssim_4x4xn_16bit(&main[4 * z * main_stride], main_stride,
                             &ref[4 * z * ref_stride], ref_stride,
                             sum0, width);
        }

        ssim += ssim_endn_16bit((const int64_t (*)[4])sum0, (const int64_t (*)[4])sum1, width - 1, max);
    }

    return ssim / ((height - 1) * (width - 1));
}

static float ssim_plane(SSIMDSPContext *dsp,
                        uint8_t *main, int main_stride,
                        uint8_t *ref, int ref_stride,
                        int width, int height, void *temp,
                        int max)
{
    int z = 0, y;
    float ssim = 0.0;
    int (*sum0)[4] = temp;
    int (*sum1)[4] = sum0 + SUM_LEN(width);

    width >>= 2;
    height >>= 2;

    for (y = 1; y < height; y++) {
        for (; z <= y; z++) {
            FFSWAP(void*, sum0, sum1);
            dsp->ssim_4x4_line(&main[4 * z * main_stride], main_stride,
                               &ref[4 * z * ref_stride], ref_stride,
                               sum0, width);
        }

        ssim += dsp->ssim_end_line((const int (*)[4])sum0, (const int (*)[4])sum1, width - 1);
    }

    return ssim / ((height - 1) * (width - 1));
}

static double ssim_db(double ssim, double weight)
{
    return 10 * log10(weight / (weight - ssim));
}

static int do_ssim(FFFrameSync *fs)
{
    AVFilterContext *ctx = fs->parent;
    SSIMContext *s = ctx->priv;
    AVFrame *master, *ref;
    AVDictionary **metadata;
    float c[4], ssimv = 0.0;
    int ret, i;

    ret = ff_framesync_dualinput_get(fs, &master, &ref);
    if (ret < 0)
        return ret;
    if (!ref)
        return ff_filter_frame(ctx->outputs[0], master);
    metadata = &master->metadata;

    s->nb_frames++;

    for (i = 0; i < s->nb_components; i++) {
        c[i] = s->ssim_plane(&s->dsp, master->data[i], master->linesize[i],
                             ref->data[i], ref->linesize[i],
                             s->planewidth[i], s->planeheight[i], s->temp,
                             s->max);
        ssimv += s->coefs[i] * c[i];
        s->ssim[i] += c[i];
    }
    for (i = 0; i < s->nb_components; i++) {
        int cidx = s->is_rgb ? s->rgba_map[i] : i;
        set_meta(metadata, "lavfi.ssim.", s->comps[i], c[cidx]);
    }
    s->ssim_total += ssimv;

    set_meta(metadata, "lavfi.ssim.All", 0, ssimv);
    set_meta(metadata, "lavfi.ssim.dB", 0, ssim_db(ssimv, 1.0));

    if (s->stats_file) {
        fprintf(s->stats_file, "n:%"PRId64" ", s->nb_frames);

        for (i = 0; i < s->nb_components; i++) {
            int cidx = s->is_rgb ? s->rgba_map[i] : i;
            fprintf(s->stats_file, "%c:%f ", s->comps[i], c[cidx]);
        }

        fprintf(s->stats_file, "All:%f (%f)\n", ssimv, ssim_db(ssimv, 1.0));
    }

    return ff_filter_frame(ctx->outputs[0], master);
}

static av_cold int init(AVFilterContext *ctx)
{
    SSIMContext *s = ctx->priv;

    if (s->stats_file_str) {
        if (!strcmp(s->stats_file_str, "-")) {
            s->stats_file = stdout;
        } else {
            s->stats_file = fopen(s->stats_file_str, "w");
            if (!s->stats_file) {
                int err = AVERROR(errno);
                char buf[128];
                av_strerror(err, buf, sizeof(buf));
                av_log(ctx, AV_LOG_ERROR, "Could not open stats file %s: %s\n",
                       s->stats_file_str, buf);
                return err;
            }
        }
    }

    s->fs.on_event = do_ssim;
    return 0;
}

static int query_formats(AVFilterContext *ctx)
{
    static const enum AVPixelFormat pix_fmts[] = {
        AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY9, AV_PIX_FMT_GRAY10,
        AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY16,
        AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P,
        AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
        AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
        AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ444P,
        AV_PIX_FMT_GBRP,
#define PF(suf) AV_PIX_FMT_YUV420##suf,  AV_PIX_FMT_YUV422##suf,  AV_PIX_FMT_YUV444##suf, AV_PIX_FMT_GBR##suf
        PF(P9), PF(P10), PF(P12), PF(P14), PF(P16),
        AV_PIX_FMT_NONE
    };

    AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
    if (!fmts_list)
        return AVERROR(ENOMEM);
    return ff_set_common_formats(ctx, fmts_list);
}

static int config_input_ref(AVFilterLink *inlink)
{
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
    AVFilterContext *ctx  = inlink->dst;
    SSIMContext *s = ctx->priv;
    int sum = 0, i;

    s->nb_components = desc->nb_components;

    if (ctx->inputs[0]->w != ctx->inputs[1]->w ||
        ctx->inputs[0]->h != ctx->inputs[1]->h) {
        av_log(ctx, AV_LOG_ERROR, "Width and height of input videos must be same.\n");
        return AVERROR(EINVAL);
    }
    if (ctx->inputs[0]->format != ctx->inputs[1]->format) {
        av_log(ctx, AV_LOG_ERROR, "Inputs must be of same pixel format.\n");
        return AVERROR(EINVAL);
    }

    s->is_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
    s->comps[0] = s->is_rgb ? 'R' : 'Y';
    s->comps[1] = s->is_rgb ? 'G' : 'U';
    s->comps[2] = s->is_rgb ? 'B' : 'V';
    s->comps[3] = 'A';

    s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
    s->planeheight[0] = s->planeheight[3] = inlink->h;
    s->planewidth[1]  = s->planewidth[2]  = AV_CEIL_RSHIFT(inlink->w, desc->log2_chroma_w);
    s->planewidth[0]  = s->planewidth[3]  = inlink->w;
    for (i = 0; i < s->nb_components; i++)
        sum += s->planeheight[i] * s->planewidth[i];
    for (i = 0; i < s->nb_components; i++)
        s->coefs[i] = (double) s->planeheight[i] * s->planewidth[i] / sum;

    s->temp = av_mallocz_array(2 * SUM_LEN(inlink->w), (desc->comp[0].depth > 8) ? sizeof(int64_t[4]) : sizeof(int[4]));
    if (!s->temp)
        return AVERROR(ENOMEM);
    s->max = (1 << desc->comp[0].depth) - 1;

    s->ssim_plane = desc->comp[0].depth > 8 ? ssim_plane_16bit : ssim_plane;
    s->dsp.ssim_4x4_line = ssim_4x4xn_8bit;
    s->dsp.ssim_end_line = ssim_endn_8bit;
    if (ARCH_X86)
        ff_ssim_init_x86(&s->dsp);

    return 0;
}

static int config_output(AVFilterLink *outlink)
{
    AVFilterContext *ctx = outlink->src;
    SSIMContext *s = ctx->priv;
    AVFilterLink *mainlink = ctx->inputs[0];
    int ret;

    ret = ff_framesync_init_dualinput(&s->fs, ctx);
    if (ret < 0)
        return ret;
    outlink->w = mainlink->w;
    outlink->h = mainlink->h;
    outlink->time_base = mainlink->time_base;
    outlink->sample_aspect_ratio = mainlink->sample_aspect_ratio;
    outlink->frame_rate = mainlink->frame_rate;

    if ((ret = ff_framesync_configure(&s->fs)) < 0)
        return ret;

    return 0;
}

static int activate(AVFilterContext *ctx)
{
    SSIMContext *s = ctx->priv;
    return ff_framesync_activate(&s->fs);
}

static av_cold void uninit(AVFilterContext *ctx)
{
    SSIMContext *s = ctx->priv;

    if (s->nb_frames > 0) {
        char buf[256];
        int i;
        buf[0] = 0;
        for (i = 0; i < s->nb_components; i++) {
            int c = s->is_rgb ? s->rgba_map[i] : i;
            av_strlcatf(buf, sizeof(buf), " %c:%f (%f)", s->comps[i], s->ssim[c] / s->nb_frames,
                        ssim_db(s->ssim[c], s->nb_frames));
        }
        av_log(ctx, AV_LOG_INFO, "SSIM%s All:%f (%f)\n", buf,
               s->ssim_total / s->nb_frames, ssim_db(s->ssim_total, s->nb_frames));
    }

    ff_framesync_uninit(&s->fs);

    if (s->stats_file && s->stats_file != stdout)
        fclose(s->stats_file);

    av_freep(&s->temp);
}

static const AVFilterPad ssim_inputs[] = {
    {
        .name         = "main",
        .type         = AVMEDIA_TYPE_VIDEO,
    },{
        .name         = "reference",
        .type         = AVMEDIA_TYPE_VIDEO,
        .config_props = config_input_ref,
    },
    { NULL }
};

static const AVFilterPad ssim_outputs[] = {
    {
        .name          = "default",
        .type          = AVMEDIA_TYPE_VIDEO,
        .config_props  = config_output,
    },
    { NULL }
};

AVFilter ff_vf_ssim = {
    .name          = "ssim",
    .description   = NULL_IF_CONFIG_SMALL("Calculate the SSIM between two video streams."),
    .preinit       = ssim_framesync_preinit,
    .init          = init,
    .uninit        = uninit,
    .query_formats = query_formats,
    .activate      = activate,
    .priv_size     = sizeof(SSIMContext),
    .priv_class    = &ssim_class,
    .inputs        = ssim_inputs,
    .outputs       = ssim_outputs,
};