aboutsummaryrefslogtreecommitdiffhomepage
path: root/video/out/vo_lavc.c
blob: be7de127f4f0a6116586825b9e29341873998fd7 (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
/*
 * video encoding using libavformat
 *
 * Copyright (C) 2010 Nicolas George <george@nsup.org>
 * Copyright (C) 2011-2012 Rudolf Polzer <divVerent@xonotic.org>
 *
 * This file is part of mpv.
 *
 * mpv 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.
 *
 * 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <stdlib.h>

#include "config.h"
#include "common/common.h"
#include "options/options.h"
#include "video/fmt-conversion.h"
#include "video/mp_image.h"
#include "mpv_talloc.h"
#include "vo.h"

#include "common/encode_lavc.h"

#include "sub/osd.h"

struct priv {
    AVStream *stream;
    AVCodecContext *codec;
    int have_first_packet;

    int harddup;

    double lastpts;
    int64_t lastipts;
    int64_t lastframeipts;
    int64_t lastencodedipts;
    int64_t mindeltapts;
    double expected_next_pts;
    mp_image_t *lastimg;
    int lastimg_wants_osd;
    int lastdisplaycount;

    AVRational worst_time_base;
    int worst_time_base_is_stream;

    bool shutdown;
};

static int preinit(struct vo *vo)
{
    struct priv *vc;
    if (!encode_lavc_available(vo->encode_lavc_ctx)) {
        MP_ERR(vo, "the option --o (output file) must be specified\n");
        return -1;
    }
    vo->priv = talloc_zero(vo, struct priv);
    vc = vo->priv;
    vc->harddup = vo->encode_lavc_ctx->options->harddup;
    return 0;
}

static void draw_image_unlocked(struct vo *vo, mp_image_t *mpi);
static void uninit(struct vo *vo)
{
    struct priv *vc = vo->priv;
    if (!vc || vc->shutdown)
        return;

    pthread_mutex_lock(&vo->encode_lavc_ctx->lock);

    if (vc->lastipts >= 0 && vc->stream)
        draw_image_unlocked(vo, NULL);

    mp_image_unrefp(&vc->lastimg);

    pthread_mutex_unlock(&vo->encode_lavc_ctx->lock);

    vc->shutdown = true;
}

static int reconfig(struct vo *vo, struct mp_image_params *params)
{
    struct priv *vc = vo->priv;
    enum AVPixelFormat pix_fmt = imgfmt2pixfmt(params->imgfmt);
    AVRational aspect = {params->p_w, params->p_h};
    uint32_t width = params->w;
    uint32_t height = params->h;

    if (!vc || vc->shutdown)
        return -1;

    pthread_mutex_lock(&vo->encode_lavc_ctx->lock);

    if (vc->stream) {
        /* NOTE:
         * in debug builds we get a "comparison between signed and unsigned"
         * warning here. We choose to ignore that; just because ffmpeg currently
         * uses a plain 'int' for these struct fields, it doesn't mean it always
         * will */
        if (width == vc->codec->width &&
                height == vc->codec->height) {
            if (aspect.num != vc->codec->sample_aspect_ratio.num ||
                    aspect.den != vc->codec->sample_aspect_ratio.den) {
                /* aspect-only changes are not critical */
                MP_WARN(vo, "unsupported pixel aspect ratio change from %d:%d to %d:%d\n",
                       vc->codec->sample_aspect_ratio.num,
                       vc->codec->sample_aspect_ratio.den,
                       aspect.num, aspect.den);
            }
            goto done;
        }

        /* FIXME Is it possible with raw video? */
        MP_ERR(vo, "resolution changes not supported.\n");
        goto error;
    }

    // When we get here, this must be the first call to reconfigure(). Thus, we
    // can rely on no existing data in vc having been allocated yet.
    // Reason:
    // - Second calls after reconfigure() already failed once fail (due to the
    //   vc->shutdown check above).
    // - Second calls after reconfigure() already succeeded once return early
    //   (due to the vc->stream check above).

    vc->lastipts = AV_NOPTS_VALUE;
    vc->lastframeipts = AV_NOPTS_VALUE;
    vc->lastencodedipts = AV_NOPTS_VALUE;

    if (pix_fmt == AV_PIX_FMT_NONE) {
        MP_FATAL(vo, "Format %s not supported by lavc.\n",
                 mp_imgfmt_to_name(params->imgfmt));
        goto error;
    }

    if (encode_lavc_alloc_stream(vo->encode_lavc_ctx,
                                 AVMEDIA_TYPE_VIDEO,
                                 &vc->stream, &vc->codec) < 0)
        goto error;
    vc->stream->sample_aspect_ratio = vc->codec->sample_aspect_ratio =
            aspect;
    vc->codec->width = width;
    vc->codec->height = height;
    vc->codec->pix_fmt = pix_fmt;

    encode_lavc_set_csp(vo->encode_lavc_ctx, vc->codec, params->color.space);
    encode_lavc_set_csp_levels(vo->encode_lavc_ctx, vc->codec, params->color.levels);

    if (encode_lavc_open_codec(vo->encode_lavc_ctx, vc->codec) < 0)
        goto error;

done:
    pthread_mutex_unlock(&vo->encode_lavc_ctx->lock);
    return 0;

error:
    pthread_mutex_unlock(&vo->encode_lavc_ctx->lock);
    vc->shutdown = true;
    return -1;
}

static int query_format(struct vo *vo, int format)
{
    enum AVPixelFormat pix_fmt = imgfmt2pixfmt(format);

    if (!vo->encode_lavc_ctx)
        return 0;

    pthread_mutex_lock(&vo->encode_lavc_ctx->lock);
    int flags = 0;
    if (encode_lavc_supports_pixfmt(vo->encode_lavc_ctx, pix_fmt))
        flags = 1;
    pthread_mutex_unlock(&vo->encode_lavc_ctx->lock);
    return flags;
}

static void write_packet(struct vo *vo, AVPacket *packet)
{
    struct priv *vc = vo->priv;

    packet->stream_index = vc->stream->index;
    if (packet->pts != AV_NOPTS_VALUE) {
        packet->pts = av_rescale_q(packet->pts,
                                   vc->codec->time_base,
                                   vc->stream->time_base);
    } else {
        MP_VERBOSE(vo, "codec did not provide pts\n");
        packet->pts = av_rescale_q(vc->lastipts,
                                   vc->worst_time_base,
                                   vc->stream->time_base);
    }
    if (packet->dts != AV_NOPTS_VALUE) {
        packet->dts = av_rescale_q(packet->dts,
                                   vc->codec->time_base,
                                   vc->stream->time_base);
    }
    if (packet->duration > 0) {
        packet->duration = av_rescale_q(packet->duration,
                                        vc->codec->time_base,
                                        vc->stream->time_base);
    } else {
        // HACK: libavformat calculates dts wrong if the initial packet
        // duration is not set, but ONLY if the time base is "high" and if we
        // have b-frames!
        if (!packet->duration)
            if (!vc->have_first_packet)
                if (vc->codec->has_b_frames
                        || vc->codec->max_b_frames)
                    if (vc->stream->time_base.num * 1000LL <=
                            vc->stream->time_base.den)
                        packet->duration = FFMAX(1, av_rescale_q(1,
                             vc->codec->time_base, vc->stream->time_base));
    }

    if (encode_lavc_write_frame(vo->encode_lavc_ctx,
                                vc->stream, packet) < 0) {
        MP_ERR(vo, "error writing at %d %d/%d\n",
               (int) packet->pts,
               vc->stream->time_base.num,
               vc->stream->time_base.den);
        return;
    }

    vc->have_first_packet = 1;
}

static void encode_video_and_write(struct vo *vo, AVFrame *frame)
{
    struct priv *vc = vo->priv;
    AVPacket packet = {0};

    int status = avcodec_send_frame(vc->codec, frame);
    if (status < 0) {
        MP_ERR(vo, "error encoding at %d %d/%d\n",
               frame ? (int) frame->pts : -1,
               vc->codec->time_base.num,
               vc->codec->time_base.den);
        return;
    }
    for (;;) {
        av_init_packet(&packet);
        status = avcodec_receive_packet(vc->codec, &packet);
        if (status == AVERROR(EAGAIN)) { // No more packets for now.
            if (frame == NULL) {
                MP_ERR(vo, "sent flush frame, got EAGAIN");
            }
            break;
        }
        if (status == AVERROR_EOF) { // No more packets, ever.
            if (frame != NULL) {
                MP_ERR(vo, "sent image frame, got EOF");
            }
            break;
        }
        if (status < 0) {
            MP_ERR(vo, "error encoding at %d %d/%d\n",
                   frame ? (int) frame->pts : -1,
                   vc->codec->time_base.num,
                   vc->codec->time_base.den);
            break;
        }
        encode_lavc_write_stats(vo->encode_lavc_ctx, vc->codec);
        write_packet(vo, &packet);
        av_packet_unref(&packet);
    }
}

static void draw_image_unlocked(struct vo *vo, mp_image_t *mpi)
{
    struct priv *vc = vo->priv;
    struct encode_lavc_context *ectx = vo->encode_lavc_ctx;
    AVCodecContext *avc;
    int64_t frameipts;
    double nextpts;

    double pts = mpi ? mpi->pts : MP_NOPTS_VALUE;

    if (!vc || vc->shutdown)
        goto done;
    if (!encode_lavc_start(ectx)) {
        MP_WARN(vo, "NOTE: skipped initial video frame (probably because audio is not there yet)\n");
        goto done;
    }
    if (pts == MP_NOPTS_VALUE) {
        if (mpi)
            MP_WARN(vo, "frame without pts, please report; synthesizing pts instead\n");
        pts = vc->expected_next_pts;
    }

    avc = vc->codec;

    if (vc->worst_time_base.den == 0) {
        //if (avc->time_base.num / avc->time_base.den >= vc->stream->time_base.num / vc->stream->time_base.den)
        if (avc->time_base.num * (double) vc->stream->time_base.den >=
                vc->stream->time_base.num * (double) avc->time_base.den) {
            MP_VERBOSE(vo, "NOTE: using codec time base "
                       "(%d/%d) for frame dropping; the stream base (%d/%d) is "
                       "not worse.\n", (int)avc->time_base.num,
                       (int)avc->time_base.den, (int)vc->stream->time_base.num,
                       (int)vc->stream->time_base.den);
            vc->worst_time_base = avc->time_base;
            vc->worst_time_base_is_stream = 0;
        } else {
            MP_WARN(vo, "NOTE: not using codec time base (%d/%d) for frame "
                    "dropping; the stream base (%d/%d) is worse.\n",
                    (int)avc->time_base.num, (int)avc->time_base.den,
                    (int)vc->stream->time_base.num, (int)vc->stream->time_base.den);
            vc->worst_time_base = vc->stream->time_base;
            vc->worst_time_base_is_stream = 1;
        }
        if (ectx->options->maxfps)
            vc->mindeltapts = ceil(vc->worst_time_base.den /
                    (vc->worst_time_base.num * ectx->options->maxfps));
        else
            vc->mindeltapts = 0;

        // NOTE: we use the following "axiom" of av_rescale_q:
        // if time base A is worse than time base B, then
        //   av_rescale_q(av_rescale_q(x, A, B), B, A) == x
        // this can be proven as long as av_rescale_q rounds to nearest, which
        // it currently does

        // av_rescale_q(x, A, B) * B = "round x*A to nearest multiple of B"
        // and:
        //    av_rescale_q(av_rescale_q(x, A, B), B, A) * A
        // == "round av_rescale_q(x, A, B)*B to nearest multiple of A"
        // == "round 'round x*A to nearest multiple of B' to nearest multiple of A"
        //
        // assume this fails. Then there is a value of x*A, for which the
        // nearest multiple of B is outside the range [(x-0.5)*A, (x+0.5)*A[.
        // Absurd, as this range MUST contain at least one multiple of B.
    }

    double timeunit = (double)vc->worst_time_base.num / vc->worst_time_base.den;

    double outpts;
    if (ectx->options->rawts)
        outpts = pts;
    else if (ectx->options->copyts) {
        // fix the discontinuity pts offset
        nextpts = pts;
        if (ectx->discontinuity_pts_offset == MP_NOPTS_VALUE) {
            ectx->discontinuity_pts_offset = ectx->next_in_pts - nextpts;
        }
        else if (fabs(nextpts + ectx->discontinuity_pts_offset - ectx->next_in_pts) > 30) {
            MP_WARN(vo, "detected an unexpected discontinuity (pts jumped by "
                    "%f seconds)\n",
                    nextpts + ectx->discontinuity_pts_offset - ectx->next_in_pts);
            ectx->discontinuity_pts_offset = ectx->next_in_pts - nextpts;
        }

        outpts = pts + ectx->discontinuity_pts_offset;
    }
    else {
        // adjust pts by knowledge of audio pts vs audio playback time
        double duration = 0;
        if (ectx->last_video_in_pts != MP_NOPTS_VALUE)
            duration = pts - ectx->last_video_in_pts;
        if (duration < 0)
            duration = timeunit;   // XXX warn about discontinuity?
        outpts = vc->lastpts + duration;
        if (ectx->audio_pts_offset != MP_NOPTS_VALUE) {
            double adj = outpts - pts - ectx->audio_pts_offset;
            adj = FFMIN(adj, duration * 0.1);
            adj = FFMAX(adj, -duration * 0.1);
            outpts -= adj;
        }
    }
    vc->lastpts = outpts;
    ectx->last_video_in_pts = pts;
    frameipts = floor((outpts + encode_lavc_getoffset(ectx, vc->codec))
                      / timeunit + 0.5);

    // calculate expected pts of next video frame
    vc->expected_next_pts = pts + timeunit;

    if (!ectx->options->rawts && ectx->options->copyts) {
        // set next allowed output pts value
        nextpts = vc->expected_next_pts + ectx->discontinuity_pts_offset;
        if (nextpts > ectx->next_in_pts)
            ectx->next_in_pts = nextpts;
    }

    // never-drop mode
    if (ectx->options->neverdrop) {
        int64_t step = vc->mindeltapts ? vc->mindeltapts : 1;
        if (frameipts < vc->lastipts + step) {
            MP_INFO(vo, "--oneverdrop increased pts by %d\n",
                    (int) (vc->lastipts - frameipts + step));
            frameipts = vc->lastipts + step;
            vc->lastpts = frameipts * timeunit - encode_lavc_getoffset(ectx, vc->codec);
        }
    }

    if (vc->lastipts != AV_NOPTS_VALUE) {

        // we have a valid image in lastimg
        while (vc->lastimg && vc->lastipts < frameipts) {
            int64_t thisduration = vc->harddup ? 1 : (frameipts - vc->lastipts);

            // we will ONLY encode this frame if it can be encoded at at least
            // vc->mindeltapts after the last encoded frame!
            int64_t skipframes =
                (vc->lastencodedipts == AV_NOPTS_VALUE)
                    ? 0
                    : vc->lastencodedipts + vc->mindeltapts - vc->lastipts;
            if (skipframes < 0)
                skipframes = 0;

            if (thisduration > skipframes) {
                AVFrame *frame = mp_image_to_av_frame(vc->lastimg);
                if (!frame)
                    abort();

                // this is a nop, unless the worst time base is the STREAM time base
                frame->pts = av_rescale_q(vc->lastipts + skipframes,
                                          vc->worst_time_base, avc->time_base);
                frame->pict_type = 0; // keep this at unknown/undefined
                frame->quality = avc->global_quality;
                encode_video_and_write(vo, frame);
                av_frame_free(&frame);

                ++vc->lastdisplaycount;
                vc->lastencodedipts = vc->lastipts + skipframes;
            }

            vc->lastipts += thisduration;
        }
    }

    if (!mpi) {
        // finish encoding
        encode_video_and_write(vo, NULL);
    } else {
        if (frameipts >= vc->lastframeipts) {
            if (vc->lastframeipts != AV_NOPTS_VALUE && vc->lastdisplaycount != 1)
                MP_INFO(vo, "Frame at pts %d got displayed %d times\n",
                        (int) vc->lastframeipts, vc->lastdisplaycount);
            talloc_free(vc->lastimg);
            vc->lastimg = mpi;
            mpi = NULL;
            vc->lastimg_wants_osd = true;

            vc->lastframeipts = vc->lastipts = frameipts;
            if (ectx->options->rawts && vc->lastipts < 0) {
                MP_ERR(vo, "why does this happen? DEBUG THIS! vc->lastipts = %lld\n", (long long) vc->lastipts);
                vc->lastipts = -1;
            }
            vc->lastdisplaycount = 0;
        } else {
            MP_INFO(vo, "Frame at pts %d got dropped "
                    "entirely because pts went backwards\n", (int) frameipts);
            vc->lastimg_wants_osd = false;
        }
    }

    if (vc->lastimg && vc->lastimg_wants_osd && vo->params) {
        struct mp_osd_res dim = osd_res_from_image_params(vo->params);

        osd_draw_on_image(vo->osd, dim, vc->lastimg->pts, OSD_DRAW_SUB_ONLY,
                          vc->lastimg);
    }

done:
    talloc_free(mpi);
}

static void draw_image(struct vo *vo, mp_image_t *mpi)
{
    pthread_mutex_lock(&vo->encode_lavc_ctx->lock);
    draw_image_unlocked(vo, mpi);
    pthread_mutex_unlock(&vo->encode_lavc_ctx->lock);
}

static void flip_page(struct vo *vo)
{
}

static int control(struct vo *vo, uint32_t request, void *data)
{
    return VO_NOTIMPL;
}

const struct vo_driver video_out_lavc = {
    .encode = true,
    .description = "video encoding using libavcodec",
    .name = "lavc",
    .untimed = true,
    .preinit = preinit,
    .query_format = query_format,
    .reconfig = reconfig,
    .control = control,
    .uninit = uninit,
    .draw_image = draw_image,
    .flip_page = flip_page,
};

// vim: sw=4 ts=4 et tw=80