aboutsummaryrefslogtreecommitdiffstats
path: root/libavcodec/libxvid.c
blob: fbd33b7065318bf7cdb8a989495499aa3679167f (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
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
/*
 * Interface to xvidcore for MPEG-4 encoding
 * Copyright (c) 2004 Adam Thayer <krevnik@comcast.net>
 *
 * 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
 */

/**
 * @file
 * Interface to xvidcore for MPEG-4 compliant encoding.
 * @author Adam Thayer (krevnik@comcast.net)
 */

#include <stdio.h>
#include <string.h>
#include <xvid.h>

#include "libavutil/avassert.h"
#include "libavutil/file_open.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mathematics.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"

#include "avcodec.h"
#include "codec_internal.h"
#include "encode.h"
#include "mpegutils.h"
#include "packet_internal.h"

#if HAVE_UNISTD_H
#include <unistd.h>
#endif

#if HAVE_IO_H
#include <io.h>
#endif

/**
 * Buffer management macros.
 */
#define BUFFER_SIZE         1024
#define BUFFER_REMAINING(x) (BUFFER_SIZE - strlen(x))
#define BUFFER_CAT(x)       (&((x)[strlen(x)]))

/**
 * Structure for the private Xvid context.
 * This stores all the private context for the codec.
 */
struct xvid_context {
    AVClass *class;
    void *encoder_handle;          /**< Handle for Xvid encoder */
    int xsize;                     /**< Frame x size */
    int ysize;                     /**< Frame y size */
    int vop_flags;                 /**< VOP flags for Xvid encoder */
    int vol_flags;                 /**< VOL flags for Xvid encoder */
    int me_flags;                  /**< Motion Estimation flags */
    int qscale;                    /**< Do we use constant scale? */
    int quicktime_format;          /**< Are we in a QT-based format? */
    char *twopassbuffer;           /**< Character buffer for two-pass */
    char *old_twopassbuffer;       /**< Old character buffer (two-pass) */
    char *twopassfile;             /**< second pass temp file name */
    int twopassfd;
    unsigned char *intra_matrix;   /**< P-Frame Quant Matrix */
    unsigned char *inter_matrix;   /**< I-Frame Quant Matrix */
    int lumi_aq;                   /**< Lumi masking as an aq method */
    int variance_aq;               /**< Variance adaptive quantization */
    int ssim;                      /**< SSIM information display mode */
    int ssim_acc;                  /**< SSIM accuracy. 0: accurate. 4: fast. */
    int gmc;
    int me_quality;                /**< Motion estimation quality. 0: fast 6: best. */
    int mpeg_quant;                /**< Quantization type. 0: H.263, 1: MPEG */
};

/**
 * Structure for the private first-pass plugin.
 */
struct xvid_ff_pass1 {
    int version;                    /**< Xvid version */
    struct xvid_context *context;   /**< Pointer to private context */
};

static int xvid_encode_close(AVCodecContext *avctx);
static int xvid_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
                             const AVFrame *picture, int *got_packet);


/*
 * Xvid 2-Pass Kludge Section
 *
 * Xvid's default 2-pass doesn't allow us to create data as we need to, so
 * this section spends time replacing the first pass plugin so we can write
 * statistic information as libavcodec requests in. We have another kludge
 * that allows us to pass data to the second pass in Xvid without a custom
 * rate-control plugin.
 */

/**
 * Initialize the two-pass plugin and context.
 *
 * @param param Input construction parameter structure
 * @param handle Private context handle
 * @return Returns XVID_ERR_xxxx on failure, or 0 on success.
 */
static int xvid_ff_2pass_create(xvid_plg_create_t *param, void **handle)
{
    struct xvid_ff_pass1 *x = (struct xvid_ff_pass1 *) param->param;
    char *log = x->context->twopassbuffer;

    /* Do a quick bounds check */
    if (!log)
        return XVID_ERR_FAIL;

    /* We use snprintf() */
    /* This is because we can safely prevent a buffer overflow */
    log[0] = 0;
    snprintf(log, BUFFER_REMAINING(log),
             "# ffmpeg 2-pass log file, using xvid codec\n");
    snprintf(BUFFER_CAT(log), BUFFER_REMAINING(log),
             "# Do not modify. libxvidcore version: %d.%d.%d\n\n",
             XVID_VERSION_MAJOR(XVID_VERSION),
             XVID_VERSION_MINOR(XVID_VERSION),
             XVID_VERSION_PATCH(XVID_VERSION));

    *handle = x->context;
    return 0;
}

/**
 * Destroy the two-pass plugin context.
 *
 * @param ref Context pointer for the plugin
 * @param param Destroy context
 * @return Returns 0, success guaranteed
 */
static int xvid_ff_2pass_destroy(struct xvid_context *ref,
                                 xvid_plg_destroy_t *param)
{
    /* Currently cannot think of anything to do on destruction */
    /* Still, the framework should be here for reference/use */
    if (ref->twopassbuffer)
        ref->twopassbuffer[0] = 0;
    return 0;
}

/**
 * Enable fast encode mode during the first pass.
 *
 * @param ref Context pointer for the plugin
 * @param param Frame data
 * @return Returns 0, success guaranteed
 */
static int xvid_ff_2pass_before(struct xvid_context *ref,
                                xvid_plg_data_t *param)
{
    int motion_remove;
    int motion_replacements;
    int vop_remove;

    /* Nothing to do here, result is changed too much */
    if (param->zone && param->zone->mode == XVID_ZONE_QUANT)
        return 0;

    /* We can implement a 'turbo' first pass mode here */
    param->quant = 2;

    /* Init values */
    motion_remove       = ~XVID_ME_CHROMA_PVOP &
                          ~XVID_ME_CHROMA_BVOP &
                          ~XVID_ME_EXTSEARCH16 &
                          ~XVID_ME_ADVANCEDDIAMOND16;
    motion_replacements = XVID_ME_FAST_MODEINTERPOLATE |
                          XVID_ME_SKIP_DELTASEARCH     |
                          XVID_ME_FASTREFINE16         |
                          XVID_ME_BFRAME_EARLYSTOP;
    vop_remove          = ~XVID_VOP_MODEDECISION_RD      &
                          ~XVID_VOP_FAST_MODEDECISION_RD &
                          ~XVID_VOP_TRELLISQUANT         &
                          ~XVID_VOP_INTER4V              &
                          ~XVID_VOP_HQACPRED;

    param->vol_flags    &= ~XVID_VOL_GMC;
    param->vop_flags    &= vop_remove;
    param->motion_flags &= motion_remove;
    param->motion_flags |= motion_replacements;

    return 0;
}

/**
 * Capture statistic data and write it during first pass.
 *
 * @param ref Context pointer for the plugin
 * @param param Statistic data
 * @return Returns XVID_ERR_xxxx on failure, or 0 on success
 */
static int xvid_ff_2pass_after(struct xvid_context *ref,
                               xvid_plg_data_t *param)
{
    char *log = ref->twopassbuffer;
    const char *frame_types = " ipbs";
    char frame_type;

    /* Quick bounds check */
    if (!log)
        return XVID_ERR_FAIL;

    /* Convert the type given to us into a character */
    if (param->type < 5 && param->type > 0)
        frame_type = frame_types[param->type];
    else
        return XVID_ERR_FAIL;

    snprintf(BUFFER_CAT(log), BUFFER_REMAINING(log),
             "%c %d %d %d %d %d %d\n",
             frame_type, param->stats.quant, param->stats.kblks,
             param->stats.mblks, param->stats.ublks,
             param->stats.length, param->stats.hlength);

    return 0;
}

/**
 * Dispatch function for our custom plugin.
 * This handles the dispatch for the Xvid plugin. It passes data
 * on to other functions for actual processing.
 *
 * @param ref Context pointer for the plugin
 * @param cmd The task given for us to complete
 * @param p1 First parameter (varies)
 * @param p2 Second parameter (varies)
 * @return Returns XVID_ERR_xxxx on failure, or 0 on success
 */
static int xvid_ff_2pass(void *ref, int cmd, void *p1, void *p2)
{
    switch (cmd) {
    case XVID_PLG_INFO:
    case XVID_PLG_FRAME:
        return 0;
    case XVID_PLG_BEFORE:
        return xvid_ff_2pass_before(ref, p1);
    case XVID_PLG_CREATE:
        return xvid_ff_2pass_create(p1, p2);
    case XVID_PLG_AFTER:
        return xvid_ff_2pass_after(ref, p1);
    case XVID_PLG_DESTROY:
        return xvid_ff_2pass_destroy(ref, p1);
    default:
        return XVID_ERR_FAIL;
    }
}

/**
 * Routine to create a global VO/VOL header for MP4 container.
 * What we do here is extract the header from the Xvid bitstream
 * as it is encoded. We also strip the repeated headers from the
 * bitstream when a global header is requested for MPEG-4 ISO
 * compliance.
 *
 * @param avctx AVCodecContext pointer to context
 * @param frame Pointer to encoded frame data
 * @param header_len Length of header to search
 * @param frame_len Length of encoded frame data
 * @return Returns new length of frame data
 */
static int xvid_strip_vol_header(AVCodecContext *avctx, AVPacket *pkt,
                                 unsigned int header_len,
                                 unsigned int frame_len)
{
    int vo_len = 0, i;

    for (i = 0; i < header_len - 3; i++) {
        if (pkt->data[i]     == 0x00 &&
            pkt->data[i + 1] == 0x00 &&
            pkt->data[i + 2] == 0x01 &&
            pkt->data[i + 3] == 0xB6) {
            vo_len = i;
            break;
        }
    }

    if (vo_len > 0) {
        /* We need to store the header, so extract it */
        if (!avctx->extradata) {
            avctx->extradata = av_malloc(vo_len);
            if (!avctx->extradata)
                return AVERROR(ENOMEM);
            memcpy(avctx->extradata, pkt->data, vo_len);
            avctx->extradata_size = vo_len;
        }
        /* Less dangerous now, memmove properly copies the two
         * chunks of overlapping data */
        memmove(pkt->data, &pkt->data[vo_len], frame_len - vo_len);
        pkt->size = frame_len - vo_len;
    }
    return 0;
}

/**
 * Routine to correct a possibly erroneous framerate being fed to us.
 * Xvid currently chokes on framerates where the ticks per frame is
 * extremely large. This function works to correct problems in this area
 * by estimating a new framerate and taking the simpler fraction of
 * the two presented.
 *
 * @param avctx Context that contains the framerate to correct.
 */
static void xvid_correct_framerate(AVCodecContext *avctx)
{
    int frate, fbase;
    int est_frate, est_fbase;
    int gcd;
    float est_fps, fps;

    frate = avctx->time_base.den;
    fbase = avctx->time_base.num;

    gcd = av_gcd(frate, fbase);
    if (gcd > 1) {
        frate /= gcd;
        fbase /= gcd;
    }

    if (frate <= 65000 && fbase <= 65000) {
        avctx->time_base.den = frate;
        avctx->time_base.num = fbase;
        return;
    }

    fps     = (float) frate / (float) fbase;
    est_fps = roundf(fps * 1000.0) / 1000.0;

    est_frate = (int) est_fps;
    if (est_fps > (int) est_fps) {
        est_frate = (est_frate + 1) * 1000;
        est_fbase = (int) roundf((float) est_frate / est_fps);
    } else
        est_fbase = 1;

    gcd = av_gcd(est_frate, est_fbase);
    if (gcd > 1) {
        est_frate /= gcd;
        est_fbase /= gcd;
    }

    if (fbase > est_fbase) {
        avctx->time_base.den = est_frate;
        avctx->time_base.num = est_fbase;
        av_log(avctx, AV_LOG_DEBUG,
               "Xvid: framerate re-estimated: %.2f, %.3f%% correction\n",
               est_fps, (((est_fps - fps) / fps) * 100.0));
    } else {
        avctx->time_base.den = frate;
        avctx->time_base.num = fbase;
    }
}

static av_cold int xvid_encode_init(AVCodecContext *avctx)
{
    int xerr, i, ret = -1;
    int xvid_flags = avctx->flags;
    struct xvid_context *x = avctx->priv_data;
    uint16_t *intra, *inter;
    int fd;

    xvid_plugin_single_t      single          = { 0 };
    struct xvid_ff_pass1      rc2pass1        = { 0 };
    xvid_plugin_2pass2_t      rc2pass2        = { 0 };
    xvid_plugin_lumimasking_t masking_l       = { 0 }; /* For lumi masking */
    xvid_plugin_lumimasking_t masking_v       = { 0 }; /* For variance AQ */
    xvid_plugin_ssim_t        ssim            = { 0 };
    xvid_gbl_init_t           xvid_gbl_init   = { 0 };
    xvid_enc_create_t         xvid_enc_create = { 0 };
    xvid_enc_plugin_t         plugins[4];

    x->twopassfd = -1;

    /* Bring in VOP flags from ffmpeg command-line */
    x->vop_flags = XVID_VOP_HALFPEL;              /* Bare minimum quality */
    if (xvid_flags & AV_CODEC_FLAG_4MV)
        x->vop_flags    |= XVID_VOP_INTER4V;      /* Level 3 */
    if (avctx->trellis)
        x->vop_flags    |= XVID_VOP_TRELLISQUANT; /* Level 5 */
    if (xvid_flags & AV_CODEC_FLAG_AC_PRED)
        x->vop_flags    |= XVID_VOP_HQACPRED;     /* Level 6 */
    if (xvid_flags & AV_CODEC_FLAG_GRAY)
        x->vop_flags    |= XVID_VOP_GREYSCALE;

    /* Decide which ME quality setting to use */
    x->me_flags = 0;
    switch (x->me_quality) {
    case 6:
    case 5:
        x->me_flags |= XVID_ME_EXTSEARCH16 |
                       XVID_ME_EXTSEARCH8;
    case 4:
    case 3:
        x->me_flags |= XVID_ME_ADVANCEDDIAMOND8 |
                       XVID_ME_HALFPELREFINE8   |
                       XVID_ME_CHROMA_PVOP      |
                       XVID_ME_CHROMA_BVOP;
    case 2:
    case 1:
        x->me_flags |= XVID_ME_ADVANCEDDIAMOND16 |
                       XVID_ME_HALFPELREFINE16;
    }

    /* Decide how we should decide blocks */
    switch (avctx->mb_decision) {
    case FF_MB_DECISION_RD:
        x->vop_flags |=  XVID_VOP_MODEDECISION_RD;
        x->me_flags  |=  XVID_ME_HALFPELREFINE8_RD    |
                         XVID_ME_QUARTERPELREFINE8_RD |
                         XVID_ME_EXTSEARCH_RD         |
                         XVID_ME_CHECKPREDICTION_RD;
    case FF_MB_DECISION_BITS:
        if (!(x->vop_flags & XVID_VOP_MODEDECISION_RD))
            x->vop_flags |= XVID_VOP_FAST_MODEDECISION_RD;
        x->me_flags |= XVID_ME_HALFPELREFINE16_RD |
                       XVID_ME_QUARTERPELREFINE16_RD;
    default:
        break;
    }

    /* Bring in VOL flags from ffmpeg command-line */
    x->vol_flags = 0;
    if (x->gmc) {
        x->vol_flags |= XVID_VOL_GMC;
        x->me_flags  |= XVID_ME_GME_REFINE;
    }
    if (xvid_flags & AV_CODEC_FLAG_QPEL) {
        x->vol_flags |= XVID_VOL_QUARTERPEL;
        x->me_flags  |= XVID_ME_QUARTERPELREFINE16;
        if (x->vop_flags & XVID_VOP_INTER4V)
            x->me_flags |= XVID_ME_QUARTERPELREFINE8;
    }

    xvid_gbl_init.version   = XVID_VERSION;
    xvid_gbl_init.debug     = 0;
    xvid_gbl_init.cpu_flags = 0;

    /* Initialize */
    xvid_global(NULL, XVID_GBL_INIT, &xvid_gbl_init, NULL);

    /* Create the encoder reference */
    xvid_enc_create.version = XVID_VERSION;

    /* Store the desired frame size */
    xvid_enc_create.width  =
    x->xsize               = avctx->width;
    xvid_enc_create.height =
    x->ysize               = avctx->height;

    /* Xvid can determine the proper profile to use */
    /* xvid_enc_create.profile = XVID_PROFILE_S_L3; */

    /* We don't use zones */
    xvid_enc_create.zones     = NULL;
    xvid_enc_create.num_zones = 0;

    xvid_enc_create.num_threads = avctx->thread_count;
#if (XVID_VERSION <= 0x010303) && (XVID_VERSION >= 0x010300)
    /* workaround for a bug in libxvidcore */
    if (avctx->height <= 16) {
        if (avctx->thread_count < 2) {
            xvid_enc_create.num_threads = 0;
        } else {
            av_log(avctx, AV_LOG_ERROR,
                   "Too small height for threads > 1.");
            return AVERROR(EINVAL);
        }
    }
#endif

    xvid_enc_create.plugins     = plugins;
    xvid_enc_create.num_plugins = 0;

    /* Initialize Buffers */
    x->twopassbuffer     = NULL;
    x->old_twopassbuffer = NULL;
    x->twopassfile       = NULL;

    if (xvid_flags & AV_CODEC_FLAG_PASS1) {
        rc2pass1.version     = XVID_VERSION;
        rc2pass1.context     = x;
        x->twopassbuffer     = av_malloc(BUFFER_SIZE);
        x->old_twopassbuffer = av_malloc(BUFFER_SIZE);
        if (!x->twopassbuffer || !x->old_twopassbuffer) {
            av_log(avctx, AV_LOG_ERROR,
                   "Xvid: Cannot allocate 2-pass log buffers\n");
            return AVERROR(ENOMEM);
        }
        x->twopassbuffer[0]     =
        x->old_twopassbuffer[0] = 0;

        plugins[xvid_enc_create.num_plugins].func  = xvid_ff_2pass;
        plugins[xvid_enc_create.num_plugins].param = &rc2pass1;
        xvid_enc_create.num_plugins++;
    } else if (xvid_flags & AV_CODEC_FLAG_PASS2) {
        rc2pass2.version = XVID_VERSION;
        rc2pass2.bitrate = avctx->bit_rate;

        fd = avpriv_tempfile("xvidff.", &x->twopassfile, 0, avctx);
        if (fd < 0) {
            av_log(avctx, AV_LOG_ERROR, "Xvid: Cannot write 2-pass pipe\n");
            return fd;
        }
        x->twopassfd = fd;

        if (!avctx->stats_in) {
            av_log(avctx, AV_LOG_ERROR,
                   "Xvid: No 2-pass information loaded for second pass\n");
            return AVERROR(EINVAL);
        }

        ret = write(fd, avctx->stats_in, strlen(avctx->stats_in));
        if (ret == -1)
            ret = AVERROR(errno);
        else if (strlen(avctx->stats_in) > ret) {
            av_log(avctx, AV_LOG_ERROR, "Xvid: Cannot write to 2-pass pipe\n");
            ret = AVERROR(EIO);
        }
        if (ret < 0)
            return ret;

        rc2pass2.filename                          = x->twopassfile;
        plugins[xvid_enc_create.num_plugins].func  = xvid_plugin_2pass2;
        plugins[xvid_enc_create.num_plugins].param = &rc2pass2;
        xvid_enc_create.num_plugins++;
    } else if (!(xvid_flags & AV_CODEC_FLAG_QSCALE)) {
        /* Single Pass Bitrate Control! */
        single.version = XVID_VERSION;
        single.bitrate = avctx->bit_rate;

        plugins[xvid_enc_create.num_plugins].func  = xvid_plugin_single;
        plugins[xvid_enc_create.num_plugins].param = &single;
        xvid_enc_create.num_plugins++;
    }

    if (avctx->lumi_masking != 0.0)
        x->lumi_aq = 1;

    /* Luminance Masking */
    if (x->lumi_aq) {
        masking_l.method                          = 0;
        plugins[xvid_enc_create.num_plugins].func = xvid_plugin_lumimasking;

        /* The old behavior is that when avctx->lumi_masking is specified,
         * plugins[...].param = NULL. Trying to keep the old behavior here. */
        plugins[xvid_enc_create.num_plugins].param =
            avctx->lumi_masking ? NULL : &masking_l;
        xvid_enc_create.num_plugins++;
    }

    /* Variance AQ */
    if (x->variance_aq) {
        masking_v.method                           = 1;
        plugins[xvid_enc_create.num_plugins].func  = xvid_plugin_lumimasking;
        plugins[xvid_enc_create.num_plugins].param = &masking_v;
        xvid_enc_create.num_plugins++;
    }

    if (x->lumi_aq && x->variance_aq )
        av_log(avctx, AV_LOG_INFO,
               "Both lumi_aq and variance_aq are enabled. The resulting quality"
               "will be the worse one of the two effects made by the AQ.\n");

    /* SSIM */
    if (x->ssim) {
        plugins[xvid_enc_create.num_plugins].func  = xvid_plugin_ssim;
        ssim.b_printstat                           = x->ssim == 2;
        ssim.acc                                   = x->ssim_acc;
        ssim.cpu_flags                             = xvid_gbl_init.cpu_flags;
        ssim.b_visualize                           = 0;
        plugins[xvid_enc_create.num_plugins].param = &ssim;
        xvid_enc_create.num_plugins++;
    }

    /* Frame Rate and Key Frames */
    xvid_correct_framerate(avctx);
    xvid_enc_create.fincr = avctx->time_base.num;
    xvid_enc_create.fbase = avctx->time_base.den;
    if (avctx->gop_size > 0)
        xvid_enc_create.max_key_interval = avctx->gop_size;
    else
        xvid_enc_create.max_key_interval = 240; /* Xvid's best default */

    /* Quants */
    if (xvid_flags & AV_CODEC_FLAG_QSCALE)
        x->qscale = 1;
    else
        x->qscale = 0;

    xvid_enc_create.min_quant[0] = avctx->qmin;
    xvid_enc_create.min_quant[1] = avctx->qmin;
    xvid_enc_create.min_quant[2] = avctx->qmin;
    xvid_enc_create.max_quant[0] = avctx->qmax;
    xvid_enc_create.max_quant[1] = avctx->qmax;
    xvid_enc_create.max_quant[2] = avctx->qmax;

    /* Quant Matrices */
    x->intra_matrix =
    x->inter_matrix = NULL;

    if (x->mpeg_quant)
        x->vol_flags |= XVID_VOL_MPEGQUANT;
    if ((avctx->intra_matrix || avctx->inter_matrix)) {
        x->vol_flags |= XVID_VOL_MPEGQUANT;

        if (avctx->intra_matrix) {
            intra           = avctx->intra_matrix;
            x->intra_matrix = av_malloc(sizeof(unsigned char) * 64);
            if (!x->intra_matrix)
                return AVERROR(ENOMEM);
        } else
            intra = NULL;
        if (avctx->inter_matrix) {
            inter           = avctx->inter_matrix;
            x->inter_matrix = av_malloc(sizeof(unsigned char) * 64);
            if (!x->inter_matrix)
                return AVERROR(ENOMEM);
        } else
            inter = NULL;

        for (i = 0; i < 64; i++) {
            if (intra)
                x->intra_matrix[i] = (unsigned char) intra[i];
            if (inter)
                x->inter_matrix[i] = (unsigned char) inter[i];
        }
    }

    /* Misc Settings */
    xvid_enc_create.frame_drop_ratio = 0;
    xvid_enc_create.global           = 0;
    if (xvid_flags & AV_CODEC_FLAG_CLOSED_GOP)
        xvid_enc_create.global |= XVID_GLOBAL_CLOSED_GOP;

    /* Determines which codec mode we are operating in */
    avctx->extradata      = NULL;
    avctx->extradata_size = 0;
    if (xvid_flags & AV_CODEC_FLAG_GLOBAL_HEADER) {
        /* In this case, we are claiming to be MPEG-4 */
        x->quicktime_format = 1;
    } else {
        /* We are claiming to be Xvid */
        x->quicktime_format = 0;
        if (!avctx->codec_tag)
            avctx->codec_tag = AV_RL32("xvid");
    }

    /* Bframes */
    xvid_enc_create.max_bframes   = avctx->max_b_frames;
    xvid_enc_create.bquant_offset = 100 * avctx->b_quant_offset;
    xvid_enc_create.bquant_ratio  = 100 * avctx->b_quant_factor;
    if (avctx->max_b_frames > 0 && !x->quicktime_format)
        xvid_enc_create.global |= XVID_GLOBAL_PACKED;

    av_assert0(xvid_enc_create.num_plugins + (!!x->ssim) + (!!x->variance_aq) + (!!x->lumi_aq) <= FF_ARRAY_ELEMS(plugins));

    /* Encode a dummy frame to get the extradata immediately */
    if (x->quicktime_format) {
        AVFrame *picture;
        AVPacket *packet;
        int size, got_packet;

        packet = av_packet_alloc();
        if (!packet)
            return AVERROR(ENOMEM);

        picture = av_frame_alloc();
        if (!picture) {
            av_packet_free(&packet);
            return AVERROR(ENOMEM);
        }

        xerr = xvid_encore(NULL, XVID_ENC_CREATE, &xvid_enc_create, NULL);
        if( xerr ) {
            av_packet_free(&packet);
            av_frame_free(&picture);
            av_log(avctx, AV_LOG_ERROR, "Xvid: Could not create encoder reference\n");
            return AVERROR_EXTERNAL;
        }
        x->encoder_handle = xvid_enc_create.handle;
        size = ((avctx->width + 1) & ~1) * ((avctx->height + 1) & ~1);
        picture->data[0] = av_malloc(size + size / 2);
        if (!picture->data[0]) {
            av_packet_free(&packet);
            av_frame_free(&picture);
            return AVERROR(ENOMEM);
        }
        picture->data[1] = picture->data[0] + size;
        picture->data[2] = picture->data[1] + size / 4;
        memset(picture->data[0], 0, size);
        memset(picture->data[1], 128, size / 2);
        xvid_encode_frame(avctx, packet, picture, &got_packet);
        av_packet_free(&packet);
        av_free(picture->data[0]);
        av_frame_free(&picture);
        xvid_encore(x->encoder_handle, XVID_ENC_DESTROY, NULL, NULL);
    }

    /* Create encoder context */
    xerr = xvid_encore(NULL, XVID_ENC_CREATE, &xvid_enc_create, NULL);
    if (xerr) {
        av_log(avctx, AV_LOG_ERROR, "Xvid: Could not create encoder reference\n");
        return AVERROR_EXTERNAL;
    }

    x->encoder_handle  = xvid_enc_create.handle;

    return 0;
}

static int xvid_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
                             const AVFrame *picture, int *got_packet)
{
    int xerr, i, ret;
    struct xvid_context *x = avctx->priv_data;
    int mb_width  = (avctx->width  + 15) / 16;
    int mb_height = (avctx->height + 15) / 16;
    char *tmp;

    xvid_enc_frame_t xvid_enc_frame = { 0 };
    xvid_enc_stats_t xvid_enc_stats = { 0 };

    if ((ret = ff_alloc_packet(avctx, pkt, mb_width*(int64_t)mb_height*MAX_MB_BYTES + FF_INPUT_BUFFER_MIN_SIZE)) < 0)
        return ret;

    /* Start setting up the frame */
    xvid_enc_frame.version = XVID_VERSION;
    xvid_enc_stats.version = XVID_VERSION;

    /* Let Xvid know where to put the frame. */
    xvid_enc_frame.bitstream = pkt->data;
    xvid_enc_frame.length    = pkt->size;

    /* Initialize input image fields */
    if (avctx->pix_fmt != AV_PIX_FMT_YUV420P) {
        av_log(avctx, AV_LOG_ERROR,
               "Xvid: Color spaces other than 420P not supported\n");
        return AVERROR(EINVAL);
    }

    xvid_enc_frame.input.csp = XVID_CSP_PLANAR; /* YUV420P */

    for (i = 0; i < 4; i++) {
        xvid_enc_frame.input.plane[i]  = picture->data[i];
        xvid_enc_frame.input.stride[i] = picture->linesize[i];
    }

    /* Encoder Flags */
    xvid_enc_frame.vop_flags = x->vop_flags;
    xvid_enc_frame.vol_flags = x->vol_flags;
    xvid_enc_frame.motion    = x->me_flags;
    xvid_enc_frame.type      =
        picture->pict_type == AV_PICTURE_TYPE_I ? XVID_TYPE_IVOP :
        picture->pict_type == AV_PICTURE_TYPE_P ? XVID_TYPE_PVOP :
        picture->pict_type == AV_PICTURE_TYPE_B ? XVID_TYPE_BVOP :
                                                  XVID_TYPE_AUTO;

    /* Pixel aspect ratio setting */
    if (avctx->sample_aspect_ratio.num < 0 || avctx->sample_aspect_ratio.num > 255 ||
        avctx->sample_aspect_ratio.den < 0 || avctx->sample_aspect_ratio.den > 255) {
        av_log(avctx, AV_LOG_WARNING,
               "Invalid pixel aspect ratio %i/%i, limit is 255/255 reducing\n",
               avctx->sample_aspect_ratio.num, avctx->sample_aspect_ratio.den);
        av_reduce(&avctx->sample_aspect_ratio.num, &avctx->sample_aspect_ratio.den,
                   avctx->sample_aspect_ratio.num,  avctx->sample_aspect_ratio.den, 255);
    }
    xvid_enc_frame.par        = XVID_PAR_EXT;
    xvid_enc_frame.par_width  = avctx->sample_aspect_ratio.num;
    xvid_enc_frame.par_height = avctx->sample_aspect_ratio.den;

    /* Quant Setting */
    if (x->qscale)
        xvid_enc_frame.quant = picture->quality / FF_QP2LAMBDA;
    else
        xvid_enc_frame.quant = 0;

    /* Matrices */
    xvid_enc_frame.quant_intra_matrix = x->intra_matrix;
    xvid_enc_frame.quant_inter_matrix = x->inter_matrix;

    /* Encode */
    xerr = xvid_encore(x->encoder_handle, XVID_ENC_ENCODE,
                       &xvid_enc_frame, &xvid_enc_stats);

    /* Two-pass log buffer swapping */
    avctx->stats_out = NULL;
    if (x->twopassbuffer) {
        tmp                  = x->old_twopassbuffer;
        x->old_twopassbuffer = x->twopassbuffer;
        x->twopassbuffer     = tmp;
        x->twopassbuffer[0]  = 0;
        if (x->old_twopassbuffer[0] != 0) {
            avctx->stats_out = x->old_twopassbuffer;
        }
    }

    if (xerr > 0) {
        int pict_type;

        *got_packet = 1;

        if (xvid_enc_stats.type == XVID_TYPE_PVOP)
            pict_type = AV_PICTURE_TYPE_P;
        else if (xvid_enc_stats.type == XVID_TYPE_BVOP)
            pict_type = AV_PICTURE_TYPE_B;
        else if (xvid_enc_stats.type == XVID_TYPE_SVOP)
            pict_type = AV_PICTURE_TYPE_S;
        else
            pict_type = AV_PICTURE_TYPE_I;

        ff_side_data_set_encoder_stats(pkt, xvid_enc_stats.quant * FF_QP2LAMBDA, NULL, 0, pict_type);

        if (xvid_enc_frame.out_flags & XVID_KEYFRAME) {
            pkt->flags  |= AV_PKT_FLAG_KEY;
            if (x->quicktime_format)
                return xvid_strip_vol_header(avctx, pkt,
                                             xvid_enc_stats.hlength, xerr);
        }

        pkt->size = xerr;

        return 0;
    } else {
        if (!xerr)
            return 0;
        av_log(avctx, AV_LOG_ERROR,
               "Xvid: Encoding Error Occurred: %i\n", xerr);
        return AVERROR_EXTERNAL;
    }
}

static av_cold int xvid_encode_close(AVCodecContext *avctx)
{
    struct xvid_context *x = avctx->priv_data;

    if (x->encoder_handle) {
        xvid_encore(x->encoder_handle, XVID_ENC_DESTROY, NULL, NULL);
        x->encoder_handle = NULL;
    }

    if (x->twopassbuffer) {
        av_freep(&x->twopassbuffer);
        av_freep(&x->old_twopassbuffer);
        avctx->stats_out = NULL;
    }
    if (x->twopassfd>=0) {
        unlink(x->twopassfile);
        close(x->twopassfd);
        x->twopassfd = -1;
    }
    av_freep(&x->twopassfile);
    av_freep(&x->intra_matrix);
    av_freep(&x->inter_matrix);

    return 0;
}

#define OFFSET(x) offsetof(struct xvid_context, x)
#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
    { "lumi_aq",     "Luminance masking AQ",            OFFSET(lumi_aq),     AV_OPT_TYPE_INT,   { .i64 = 0 },       0,       1, VE         },
    { "variance_aq", "Variance AQ",                     OFFSET(variance_aq), AV_OPT_TYPE_INT,   { .i64 = 0 },       0,       1, VE         },
    { "ssim",        "Show SSIM information to stdout", OFFSET(ssim),        AV_OPT_TYPE_INT,   { .i64 = 0 },       0,       2, VE, .unit = "ssim" },
    { "off",         NULL,                                                0, AV_OPT_TYPE_CONST, { .i64 = 0 }, INT_MIN, INT_MAX, VE, .unit = "ssim" },
    { "avg",         NULL,                                                0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN, INT_MAX, VE, .unit = "ssim" },
    { "frame",       NULL,                                                0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN, INT_MAX, VE, .unit = "ssim" },
    { "ssim_acc",    "SSIM accuracy",                   OFFSET(ssim_acc),    AV_OPT_TYPE_INT,   { .i64 = 2 },       0,       4, VE         },
    { "gmc",         "use GMC",                         OFFSET(gmc),         AV_OPT_TYPE_INT,   { .i64 = 0 },       0,       1, VE         },
    { "me_quality",  "Motion estimation quality",       OFFSET(me_quality),  AV_OPT_TYPE_INT,   { .i64 = 4 },       0,       6, VE         },
    { "mpeg_quant",  "Use MPEG quantizers instead of H.263", OFFSET(mpeg_quant), AV_OPT_TYPE_INT, { .i64 = 0 },     0,       1, VE         },
    { NULL },
};

static const AVClass xvid_class = {
    .class_name = "libxvid",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
};

const FFCodec ff_libxvid_encoder = {
    .p.name         = "libxvid",
    CODEC_LONG_NAME("libxvidcore MPEG-4 part 2"),
    .p.type         = AVMEDIA_TYPE_VIDEO,
    .p.id           = AV_CODEC_ID_MPEG4,
    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
    .priv_data_size = sizeof(struct xvid_context),
    .init           = xvid_encode_init,
    FF_CODEC_ENCODE_CB(xvid_encode_frame),
    .close          = xvid_encode_close,
    .p.pix_fmts     = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE },
    .color_ranges   = AVCOL_RANGE_MPEG,
    .p.priv_class   = &xvid_class,
    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
    .p.wrapper_name = "libxvid",
};