summaryrefslogtreecommitdiffstats
path: root/video/filter/vf_vapoursynth.c
blob: c09563596d0a7597ed85997bc1ca62995ee520d8 (plain)
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
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
/*
 * This file is part of mpv.
 *
 * mpv is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * mpv 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with mpv.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <pthread.h>
#include <assert.h>

#include <VapourSynth.h>
#include <VSHelper.h>

#include <libavutil/rational.h>

#include "config.h"

#include "common/msg.h"
#include "options/m_option.h"
#include "options/path.h"

#include "video/img_format.h"
#include "video/mp_image.h"
#include "video/sws_utils.h"
#include "vf.h"

struct vf_priv_s {
    VSCore *vscore;
    const VSAPI *vsapi;
    VSNodeRef *out_node;
    VSNodeRef *in_node;

    const struct script_driver *drv;
    // drv_vss
    struct VSScript *se;
    // drv_lazy
    struct lua_State *ls;
    VSNodeRef **gc_noderef;
    int num_gc_noderef;
    VSMap **gc_map;
    int num_gc_map;

    struct mp_image_params fmt_in;

    pthread_mutex_t lock;
    pthread_cond_t wakeup;

    // --- the following members are all protected by lock
    struct mp_image *next_image;// used to compute frame duration of oldest image
    struct mp_image **buffered; // oldest image first
    int num_buffered;
    int in_frameno;             // frame number of buffered[0] (the oldest)
    int out_frameno;            // frame number of first requested/ready frame
    double out_pts;             // pts corresponding to first requested/ready frame
    struct mp_image **requested;// frame callback results (can point to dummy_img)
                                // requested[0] is the frame to return first
    int max_requests;           // upper bound for requested[] array
    bool failed;                // frame callback returned with an error
    bool shutdown;              // ask node to return
    bool initializing;          // filters are being built
    bool in_node_active;        // node might still be called

    // --- options
    char *cfg_file;
    int cfg_maxbuffer;
    int cfg_maxrequests;
};

// priv->requested[n] points to this if a request for frame n is in-progress
static const struct mp_image dummy_img;

struct script_driver {
    int (*init)(struct vf_instance *vf);        // first time init
    void (*uninit)(struct vf_instance *vf);     // last time uninit
    int (*load_core)(struct vf_instance *vf);   // make vsapi/vscore available
    int (*load)(struct vf_instance *vf, VSMap *vars); // also set p->out_node
    void (*unload)(struct vf_instance *vf);     // unload script and maybe vs
};

struct mpvs_fmt {
    VSPresetFormat vs;
    int mp;
};

static const struct mpvs_fmt mpvs_fmt_table[] = {
    {pfYUV420P8, IMGFMT_420P},
    {pfYUV422P8, IMGFMT_422P},
    {pfYUV444P8, IMGFMT_444P},
    {pfYUV410P8, IMGFMT_410P},
    {pfYUV411P8, IMGFMT_411P},
    {pfYUV440P8, IMGFMT_440P},
    {pfYUV420P9, IMGFMT_420P9},
    {pfYUV422P9, IMGFMT_422P9},
    {pfYUV444P9, IMGFMT_444P9},
    {pfYUV420P10, IMGFMT_420P10},
    {pfYUV422P10, IMGFMT_422P10},
    {pfYUV444P10, IMGFMT_444P10},
    {pfYUV420P16, IMGFMT_420P16},
    {pfYUV422P16, IMGFMT_422P16},
    {pfYUV444P16, IMGFMT_444P16},
    {pfNone}
};

static VSPresetFormat mp_to_vs(int imgfmt)
{
    for (int n = 0; mpvs_fmt_table[n].mp; n++) {
        if (mpvs_fmt_table[n].mp == imgfmt)
            return mpvs_fmt_table[n].vs;
    }
    return pfNone;
}

static int mp_from_vs(VSPresetFormat vs)
{
    for (int n = 0; mpvs_fmt_table[n].mp; n++) {
        if (mpvs_fmt_table[n].vs == vs)
            return mpvs_fmt_table[n].mp;
    }
    return pfNone;
}

static void copy_mp_to_vs_frame_props_map(struct vf_priv_s *p, VSMap *map,
                                          struct mp_image *img)
{
    struct mp_image_params *params = &img->params;
    if (params->d_w > 0 && params->d_h > 0) {
        AVRational dar = {params->d_w, params->d_h};
        AVRational asp = {params->w, params->h};
        AVRational par = av_div_q(dar, asp);

        p->vsapi->propSetInt(map, "_SARNum", par.num, 0);
        p->vsapi->propSetInt(map, "_SARDen", par.den, 0);
    }
    if (params->colorlevels) {
        p->vsapi->propSetInt(map, "_ColorRange",
                params->colorlevels == MP_CSP_LEVELS_TV, 0);
    }
    // The docs explicitly say it uses libavcodec values.
    p->vsapi->propSetInt(map, "_ColorSpace",
            mp_csp_to_avcol_spc(params->colorspace), 0);
    if (params->chroma_location) {
        p->vsapi->propSetInt(map, "_ChromaLocation",
                params->chroma_location == MP_CHROMA_CENTER, 0);
    }
    char pict_type = 0;
    switch (img->pict_type) {
    case 1: pict_type = 'I'; break;
    case 2: pict_type = 'P'; break;
    case 3: pict_type = 'B'; break;
    }
    if (pict_type)
        p->vsapi->propSetData(map, "_PictType", &pict_type, 1, 0);
    p->vsapi->propSetInt(map, "_FieldBased",
            !!(img->fields & MP_IMGFIELD_INTERLACED), 0);
    p->vsapi->propSetInt(map, "_Field",
            !!(img->fields & MP_IMGFIELD_TOP_FIRST), 0);
}

static int set_vs_frame_props(struct vf_priv_s *p, VSFrameRef *frame,
                              struct mp_image *img, int dur_num, int dur_den)
{
    VSMap *map = p->vsapi->getFramePropsRW(frame);
    if (!map)
        return -1;
    p->vsapi->propSetInt(map, "_DurationNum", dur_num, 0);
    p->vsapi->propSetInt(map, "_DurationDen", dur_den, 0);
    copy_mp_to_vs_frame_props_map(p, map, img);
    return 0;
}

static VSFrameRef *alloc_vs_frame(struct vf_priv_s *p, struct mp_image_params *fmt)
{
    const VSFormat *vsfmt =
        p->vsapi->getFormatPreset(mp_to_vs(fmt->imgfmt), p->vscore);
    return p->vsapi->newVideoFrame(vsfmt, fmt->w, fmt->h, NULL, p->vscore);
}

static struct mp_image map_vs_frame(struct vf_priv_s *p, const VSFrameRef *ref,
                                    bool w)
{
    const VSFormat *fmt = p->vsapi->getFrameFormat(ref);

    struct mp_image img = {0};
    mp_image_setfmt(&img, mp_from_vs(fmt->id));
    mp_image_set_size(&img, p->vsapi->getFrameWidth(ref, 0),
                            p->vsapi->getFrameHeight(ref, 0));

    for (int n = 0; n < img.num_planes; n++) {
        if (w) {
            img.planes[n] = p->vsapi->getWritePtr((VSFrameRef *)ref, n);
        } else {
            img.planes[n] = (uint8_t *)p->vsapi->getReadPtr(ref, n);
        }
        img.stride[n] = p->vsapi->getStride(ref, n);
    }

    return img;
}

static void drain_oldest_buffered_frame(struct vf_priv_s *p)
{
    if (!p->num_buffered)
        return;
    talloc_free(p->buffered[0]);
    for (int n = 0; n < p->num_buffered - 1; n++)
        p->buffered[n] = p->buffered[n + 1];
    p->num_buffered--;
    p->in_frameno++;
}

static void VS_CC vs_frame_done(void *userData, const VSFrameRef *f, int n,
                                VSNodeRef *node, const char *errorMsg)
{
    struct vf_instance *vf = userData;
    struct vf_priv_s *p = vf->priv;

    pthread_mutex_lock(&p->lock);

    // If these assertions fail, n is an unrequested frame (or filtered twice).
    assert(n >= p->out_frameno && n < p->out_frameno + p->max_requests);
    int index = n - p->out_frameno;
    MP_DBG(vf, "filtered frame %d (%d)\n", n, index);
    assert(p->requested[index] == &dummy_img);

    struct mp_image *res = NULL;
    if (f) {
        struct mp_image img = map_vs_frame(p, f, false);
        img.pts = MP_NOPTS_VALUE;
        const VSMap *map = p->vsapi->getFramePropsRO(f);
        if (map) {
            int err1, err2;
            int num = p->vsapi->propGetInt(map, "_DurationNum", 0, &err1);
            int den = p->vsapi->propGetInt(map, "_DurationDen", 0, &err2);
            if (!err1 && !err2)
                img.pts = num / (double)den; // abusing pts for frame length
        }
        if (img.pts == MP_NOPTS_VALUE)
            MP_ERR(vf, "No PTS after filter at frame %d!\n", n);
        res = mp_image_new_copy(&img);
        p->vsapi->freeFrame(f);
    }
    if (!res) {
        p->failed = true;
        MP_ERR(vf, "Filter error at frame %d: %s\n", n, errorMsg);
    }
    p->requested[index] = res;
    pthread_cond_broadcast(&p->wakeup);
    pthread_mutex_unlock(&p->lock);
}

static bool locked_need_input(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;
    return p->num_buffered < MP_TALLOC_ELEMS(p->buffered);
}

// Return true if progress was made.
static bool locked_read_output(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;
    bool r = false;

    // Move finished frames from the request slots to the vf output queue.
    while (p->requested[0] && p->requested[0] != &dummy_img) {
        struct mp_image *out = p->requested[0];
        if (out->pts != MP_NOPTS_VALUE) {
            double duration = out->pts;
            out->pts = p->out_pts;
            p->out_pts += duration;
        }
        vf_add_output_frame(vf, out);
        for (int n = 0; n < p->max_requests - 1; n++)
            p->requested[n] = p->requested[n + 1];
        p->requested[p->max_requests - 1] = NULL;
        p->out_frameno++;
        r = true;
    }

    // Don't request frames if we haven't sent any input yet.
    if (p->num_buffered + p->in_frameno == 0)
        return r;

    // Request new future frames as far as possible.
    for (int n = 0; n < p->max_requests; n++) {
        if (!p->requested[n]) {
            // Note: this assumes getFrameAsync() will never call
            //       infiltGetFrame (if it does, we would deadlock)
            p->requested[n] = (struct mp_image *)&dummy_img;
            p->failed = false;
            MP_DBG(vf, "requesting frame %d (%d)\n", p->out_frameno + n, n);
            p->vsapi->getFrameAsync(p->out_frameno + n, p->out_node,
                                    vs_frame_done, vf);
        }
    }

    return r;
}

static int filter_ext(struct vf_instance *vf, struct mp_image *mpi)
{
    struct vf_priv_s *p = vf->priv;
    int ret = 0;

    if (!p->out_node) {
        talloc_free(mpi);
        return -1;
    }

    MPSWAP(struct mp_image *, p->next_image, mpi);

    if (!mpi)
        return 0;

    // Turn PTS into frame duration (the pts field is abused for storing it)
    if (p->out_pts == MP_NOPTS_VALUE)
        p->out_pts = mpi->pts;
    mpi->pts = p->next_image ? p->next_image->pts - mpi->pts : 0;

    // Try to get new frames until we get rid of the input mpi.
    pthread_mutex_lock(&p->lock);
    while (1) {
        // Not sure what we do on errors, but at least don't deadlock.
        if (p->failed) {
            p->failed = false;
            talloc_free(mpi);
            ret = -1;
            break;
        }

        // Make the input frame available to infiltGetFrame().
        if (mpi && locked_need_input(vf)) {
            p->buffered[p->num_buffered++] = talloc_steal(p->buffered, mpi);
            mpi = NULL;
            pthread_cond_broadcast(&p->wakeup);
        }

        locked_read_output(vf);

        if (!mpi)
            break;
        pthread_cond_wait(&p->wakeup, &p->lock);
    }
    pthread_mutex_unlock(&p->lock);
    return ret;
}

// Fetch 1 outout frame, or 0 if we probably need new input.
static int filter_out(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;
    int ret = 0;
    pthread_mutex_lock(&p->lock);
    while (1) {
        if (p->failed) {
            ret = -1;
            break;
        }
        if (locked_read_output(vf))
            break;
        // If the VS filter wants new input, there's no guarantee that we can
        // actually finish any time soon without feeding new input.
        if (locked_need_input(vf))
            break;
        pthread_cond_wait(&p->wakeup, &p->lock);
    }
    pthread_mutex_unlock(&p->lock);
    return ret;
}

static void VS_CC infiltInit(VSMap *in, VSMap *out, void **instanceData,
                             VSNode *node, VSCore *core, const VSAPI *vsapi)
{
    struct vf_instance *vf = *instanceData;
    struct vf_priv_s *p = vf->priv;

    // Note: this is called from createFilter, so no need for locking.

    VSVideoInfo fmt = {
        .format = p->vsapi->getFormatPreset(mp_to_vs(p->fmt_in.imgfmt), p->vscore),
        .width = p->fmt_in.w,
        .height = p->fmt_in.h,
    };
    if (!fmt.format) {
        p->vsapi->setError(out, "Unsupported input format.\n");
        return;
    }

    p->vsapi->setVideoInfo(&fmt, 1, node);
    p->in_node_active = true;
}

static const VSFrameRef *VS_CC infiltGetFrame(int frameno, int activationReason,
    void **instanceData, void **frameData,
    VSFrameContext *frameCtx, VSCore *core,
    const VSAPI *vsapi)
{
    struct vf_instance *vf = *instanceData;
    struct vf_priv_s *p = vf->priv;
    VSFrameRef *ret = NULL;

    pthread_mutex_lock(&p->lock);
    MP_DBG(vf, "VS asking for frame %d (at %d)\n", frameno, p->in_frameno);
    while (1) {
        if (p->shutdown) {
            p->vsapi->setFilterError("EOF or filter reinit/uninit", frameCtx);
            break;
        }
        if (p->initializing) {
            MP_WARN(vf, "Frame requested during init! This is unsupported.\n"
                        "Returning black dummy frame with 0 duration.\n");
            ret = alloc_vs_frame(p, &vf->fmt_in);
            if (!ret) {
                p->vsapi->setFilterError("Could not allocate VS frame", frameCtx);
                break;
            }
            struct mp_image vsframe = map_vs_frame(p, ret, true);
            mp_image_clear(&vsframe, 0, 0, vf->fmt_in.w, vf->fmt_in.h);
            struct mp_image dummy = {0};
            mp_image_set_params(&dummy, &vf->fmt_in);
            set_vs_frame_props(p, ret, &dummy, 0, 1);
            break;
        }
        if (frameno < p->in_frameno) {
            char msg[180];
            snprintf(msg, sizeof(msg),
                "Frame %d requested, but only have frames starting from %d. "
                "Try increasing the buffered-frames suboption.",
                frameno, p->in_frameno);
            MP_FATAL(vf, "%s\n", msg);
            p->vsapi->setFilterError(msg, frameCtx);
            break;
        }
        if (frameno >= p->in_frameno + MP_TALLOC_ELEMS(p->buffered)) {
            // Too far in the future. Remove frames, so that the main thread can
            // queue new frames.
            if (p->num_buffered) {
                drain_oldest_buffered_frame(p);
                pthread_cond_broadcast(&p->wakeup);
                continue;
            }
        }
        if (frameno < p->in_frameno + p->num_buffered) {
            struct mp_image *img = p->buffered[frameno - p->in_frameno];
            ret = alloc_vs_frame(p, &img->params);
            if (!ret) {
                p->vsapi->setFilterError("Could not allocate VS frame", frameCtx);
                break;
            }
            struct mp_image vsframe = map_vs_frame(p, ret, true);
            mp_image_copy(&vsframe, img);
            int res = 1e6;
            int dur = img->pts * res + 0.5;
            set_vs_frame_props(p, ret, img, dur, res);
            break;
        }
        pthread_cond_wait(&p->wakeup, &p->lock);
    }
    pthread_cond_broadcast(&p->wakeup);
    pthread_mutex_unlock(&p->lock);
    return ret;
}

static void VS_CC infiltFree(void *instanceData, VSCore *core, const VSAPI *vsapi)
{
    struct vf_instance *vf = instanceData;
    struct vf_priv_s *p = vf->priv;

    pthread_mutex_lock(&p->lock);
    p->in_node_active = false;
    pthread_cond_broadcast(&p->wakeup);
    pthread_mutex_unlock(&p->lock);
}

// number of getAsyncFrame calls in progress
// must be called with p->lock held
static int num_requested(struct vf_priv_s *p)
{
    int r = 0;
    for (int n = 0; n < p->max_requests; n++)
        r += p->requested[n] == &dummy_img;
    return r;
}

static void destroy_vs(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;

    MP_DBG(vf, "destroying VS filters\n");

    // Wait until our frame callbacks return.
    pthread_mutex_lock(&p->lock);
    p->initializing = false;
    p->shutdown = true;
    pthread_cond_broadcast(&p->wakeup);
    while (num_requested(p))
        pthread_cond_wait(&p->wakeup, &p->lock);
    pthread_mutex_unlock(&p->lock);

    MP_DBG(vf, "all requests terminated\n");

    if (p->in_node)
        p->vsapi->freeNode(p->in_node);
    if (p->out_node)
        p->vsapi->freeNode(p->out_node);
    p->in_node = p->out_node = NULL;

    p->drv->unload(vf);

    assert(!p->in_node_active);
    assert(num_requested(p) == 0); // async callback didn't return?

    p->shutdown = false;
    // Kill filtered images that weren't returned yet
    for (int n = 0; n < p->max_requests; n++)
        mp_image_unrefp(&p->requested[n]);
    // Kill queued frames too
    for (int n = 0; n < p->num_buffered; n++)
        talloc_free(p->buffered[n]);
    p->num_buffered = 0;
    talloc_free(p->next_image);
    p->next_image = NULL;
    p->out_pts = MP_NOPTS_VALUE;
    p->out_frameno = p->in_frameno = 0;
    p->failed = false;

    MP_DBG(vf, "uninitialized.\n");
}

static int reinit_vs(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;
    VSMap *vars = NULL, *in = NULL, *out = NULL;
    int res = -1;

    destroy_vs(vf);

    MP_DBG(vf, "initializing...\n");
    p->initializing = true;

    if (p->drv->load_core(vf) < 0 || !p->vsapi || !p->vscore) {
        MP_FATAL(vf, "Could not get vapoursynth API handle.\n");
        goto error;
    }

    in = p->vsapi->createMap();
    out = p->vsapi->createMap();
    vars = p->vsapi->createMap();
    if (!in || !out || !vars)
        goto error;

    p->vsapi->createFilter(in, out, "Input", infiltInit, infiltGetFrame,
                           infiltFree, fmSerial, 0, vf, p->vscore);
    int vserr;
    p->in_node = p->vsapi->propGetNode(out, "clip", 0, &vserr);
    if (!p->in_node) {
        MP_FATAL(vf, "Could not get our own input node.\n");
        goto error;
    }

    if (p->vsapi->propSetNode(vars, "video_in", p->in_node, 0))
        goto error;

    p->vsapi->propSetInt(vars, "video_in_dw", p->fmt_in.d_w, 0);
    p->vsapi->propSetInt(vars, "video_in_dh", p->fmt_in.d_h, 0);

    if (p->drv->load(vf, vars) < 0)
        goto error;
    if (!p->out_node) {
        MP_FATAL(vf, "Could not get script output node.\n");
        goto error;
    }

    const VSVideoInfo *vi = p->vsapi->getVideoInfo(p->out_node);
    if (!isConstantFormat(vi)) {
        MP_FATAL(vf, "Video format is required to be constant.\n");
        goto error;
    }

    pthread_mutex_lock(&p->lock);
    p->initializing = false;
    pthread_mutex_unlock(&p->lock);
    MP_DBG(vf, "initialized.\n");
    res = 0;
error:
    if (p->vsapi) {
        p->vsapi->freeMap(in);
        p->vsapi->freeMap(out);
        p->vsapi->freeMap(vars);
    }
    if (res < 0)
        destroy_vs(vf);
    return res;
}

static int config(struct vf_instance *vf, int width, int height,
                  int d_width, int d_height, unsigned int flags,
                  unsigned int fmt)
{
    struct vf_priv_s *p = vf->priv;

    p->fmt_in = (struct mp_image_params){
        .imgfmt = fmt,
        .w = width,
        .h = height,
        .d_w = d_width,
        .d_h = d_height,
    };

    if (reinit_vs(vf) < 0)
        return 0;

    const VSVideoInfo *vi = p->vsapi->getVideoInfo(p->out_node);
    fmt = mp_from_vs(vi->format->id);
    if (!fmt) {
        MP_FATAL(vf, "Unsupported output format.\n");
        destroy_vs(vf);
        return 0;
    }

    vf_rescale_dsize(&d_width, &d_height, width, height, vi->width, vi->height);

    return vf_next_config(vf, vi->width, vi->height, d_width, d_height, flags, fmt);
}

static int query_format(struct vf_instance *vf, unsigned int fmt)
{
    return mp_to_vs(fmt) != pfNone ? VFCAP_CSP_SUPPORTED : 0;
}

static int control(vf_instance_t *vf, int request, void *data)
{
    struct vf_priv_s *p = vf->priv;
    switch (request) {
    case VFCTRL_SEEK_RESET:
        if (p->out_node && reinit_vs(vf) < 0)
            return CONTROL_ERROR;
        return CONTROL_OK;
    }
    return CONTROL_UNKNOWN;
}

static void uninit(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;

    destroy_vs(vf);
    p->drv->uninit(vf);

    pthread_cond_destroy(&p->wakeup);
    pthread_mutex_destroy(&p->lock);
}
static int vf_open(vf_instance_t *vf)
{
    struct vf_priv_s *p = vf->priv;
    if (p->drv->init(vf) < 0)
        return 0;
    if (!p->cfg_file || !p->cfg_file[0]) {
        MP_FATAL(vf, "'file' parameter must be set.\n");
        return 0;
    }
    talloc_steal(vf, p->cfg_file);
    p->cfg_file = mp_get_user_path(vf, vf->chain->global, p->cfg_file);

    pthread_mutex_init(&p->lock, NULL);
    pthread_cond_init(&p->wakeup, NULL);
    vf->reconfig = NULL;
    vf->config = config;
    vf->filter_ext = filter_ext;
    vf->filter_out = filter_out;
    vf->query_format = query_format;
    vf->control = control;
    vf->uninit = uninit;
    int maxbuffer = p->cfg_maxbuffer * p->cfg_maxrequests;
    p->buffered = talloc_array(vf, struct mp_image *, maxbuffer);
    p->max_requests = p->cfg_maxrequests;
    p->requested = talloc_zero_array(vf, struct mp_image *, p->max_requests);
    return 1;
}

#define OPT_BASE_STRUCT struct vf_priv_s
static const m_option_t vf_opts_fields[] = {
    OPT_STRING("file", cfg_file, 0),
    OPT_INTRANGE("buffered-frames", cfg_maxbuffer, 0, 1, 9999, OPTDEF_INT(4)),
    OPT_INTRANGE("concurrent-frames", cfg_maxrequests, 0, 1, 99, OPTDEF_INT(2)),
    {0}
};

#if HAVE_VAPOURSYNTH

#include <VSScript.h>

static int drv_vss_init(struct vf_instance *vf)
{
    if (!vsscript_init()) {
        MP_FATAL(vf, "Could not initialize VapourSynth scripting.\n");
        return -1;
    }
    return 0;
}

static void drv_vss_uninit(struct vf_instance *vf)
{
    vsscript_finalize();
}

static int drv_vss_load_core(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;

    // First load an empty script to get a VSScript, so that we get the vsapi
    // and vscore.
    if (vsscript_evaluateScript(&p->se, "", NULL, 0))
        return -1;
    p->vsapi = vsscript_getVSApi();
    p->vscore = vsscript_getCore(p->se);
    return 0;
}

static int drv_vss_load(struct vf_instance *vf, VSMap *vars)
{
    struct vf_priv_s *p = vf->priv;

    vsscript_setVariable(p->se, vars);

    if (vsscript_evaluateFile(&p->se, p->cfg_file, 0)) {
        MP_FATAL(vf, "Script evaluation failed:\n%s\n", vsscript_getError(p->se));
        return -1;
    }
    p->out_node = vsscript_getOutput(p->se, 0);
    return 0;
}

static void drv_vss_unload(struct vf_instance *vf)
{
    struct vf_priv_s *p = vf->priv;

    if (p->se)
        vsscript_freeScript(p->se);
    p->se = NULL;
    p->vsapi = NULL;
    p->vscore = NULL;
}

static const struct script_driver drv_vss = {
    .init = drv_vss_init,
    .uninit = drv_vss_uninit,
    .load_core = drv_vss_load_core,
    .load = drv_vss_load,
    .unload = drv_vss_unload,
};

static int vf_open_vss(vf_instance_t *vf)
{
    struct vf_priv_s *p = vf->priv;
    p->drv = &drv_vss;
    return vf_open(vf);
}

const vf_info_t vf_info_vapoursynth = {
    .description = "VapourSynth bridge (Python)",
    .name = "vapoursynth",
    .open = vf_open_vss,
    .priv_size = sizeof(struct vf_priv_s),
    .options = vf_opts_fields,
};

#endif

#if HAVE_VAPOURSYNTH_LAZY

#include <lua.h>
#include <lualib.h>
#include <lauxlib.h>

#if LUA_VERSION_NUM <= 501
#define mp_cpcall lua_cpcall
#define FUCKYOUOHGODWHY(L) lua_pushvalue(L, LUA_GLOBALSINDEX)
#else
// Curse whoever had this stupid idea. Curse whoever thought it would be a good
// idea not to include an emulated lua_cpcall() even more.
static int mp_cpcall (lua_State *L, lua_CFunction func, void *ud)
{
    lua_pushcfunction(L, func); // doesn't allocate in 5.2 (but does in 5.1)
    lua_pushlightuserdata(L, ud);
    ret