avisynth: Bump minimum required version to interface version 6
[libav.git] / libavformat / avisynth.c
1 /*
2 * AviSynth/AvxSynth support
3 * Copyright (c) 2012 AvxSynth Team.
4 *
5 * This file is part of Libav.
6 *
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "libavutil/internal.h"
23 #include "libavcodec/internal.h"
24 #include "avformat.h"
25 #include "internal.h"
26
27 /* Enable function pointer definitions for runtime loading. */
28 #define AVSC_NO_DECLSPEC
29
30 /* Platform-specific directives for AviSynth vs AvxSynth. */
31 #ifdef _WIN32
32 #include <windows.h>
33 #undef EXTERN_C
34 #include <avisynth/avisynth_c.h>
35 #define AVISYNTH_LIB "avisynth"
36 #define USING_AVISYNTH
37 #else
38 #include <dlfcn.h>
39 #include <avxsynth/avxsynth_c.h>
40 #if defined (__APPLE__)
41 #define AVISYNTH_LIB "libavxsynth.dylib"
42 #else
43 #define AVISYNTH_LIB "libavxsynth.so"
44 #endif
45
46 #define LoadLibrary(x) dlopen(x, RTLD_NOW | RTLD_LOCAL)
47 #define GetProcAddress dlsym
48 #define FreeLibrary dlclose
49 #endif
50
51 typedef struct AviSynthLibrary {
52 void *library;
53 #define AVSC_DECLARE_FUNC(name) name ## _func name
54 AVSC_DECLARE_FUNC(avs_bit_blt);
55 AVSC_DECLARE_FUNC(avs_clip_get_error);
56 AVSC_DECLARE_FUNC(avs_create_script_environment);
57 AVSC_DECLARE_FUNC(avs_delete_script_environment);
58 AVSC_DECLARE_FUNC(avs_get_audio);
59 AVSC_DECLARE_FUNC(avs_get_error);
60 AVSC_DECLARE_FUNC(avs_get_frame);
61 AVSC_DECLARE_FUNC(avs_get_version);
62 AVSC_DECLARE_FUNC(avs_get_video_info);
63 AVSC_DECLARE_FUNC(avs_invoke);
64 AVSC_DECLARE_FUNC(avs_release_clip);
65 AVSC_DECLARE_FUNC(avs_release_value);
66 AVSC_DECLARE_FUNC(avs_release_video_frame);
67 AVSC_DECLARE_FUNC(avs_take_clip);
68 #ifdef USING_AVISYNTH
69 AVSC_DECLARE_FUNC(avs_bits_per_pixel);
70 AVSC_DECLARE_FUNC(avs_get_height_p);
71 AVSC_DECLARE_FUNC(avs_get_pitch_p);
72 AVSC_DECLARE_FUNC(avs_get_read_ptr_p);
73 AVSC_DECLARE_FUNC(avs_get_row_size_p);
74 AVSC_DECLARE_FUNC(avs_is_yv24);
75 AVSC_DECLARE_FUNC(avs_is_yv16);
76 AVSC_DECLARE_FUNC(avs_is_yv411);
77 AVSC_DECLARE_FUNC(avs_is_y8);
78 #endif
79 #undef AVSC_DECLARE_FUNC
80 } AviSynthLibrary;
81
82 typedef struct AviSynthContext {
83 AVS_ScriptEnvironment *env;
84 AVS_Clip *clip;
85 const AVS_VideoInfo *vi;
86
87 /* avisynth_read_packet_video() iterates over this. */
88 int n_planes;
89 const int *planes;
90
91 int curr_stream;
92 int curr_frame;
93 int64_t curr_sample;
94
95 int error;
96
97 /* Linked list pointers. */
98 struct AviSynthContext *next;
99 } AviSynthContext;
100
101 static const int avs_planes_packed[1] = { 0 };
102 static const int avs_planes_grey[1] = { AVS_PLANAR_Y };
103 static const int avs_planes_yuv[3] = { AVS_PLANAR_Y, AVS_PLANAR_U,
104 AVS_PLANAR_V };
105
106 /* A conflict between C++ global objects, atexit, and dynamic loading requires
107 * us to register our own atexit handler to prevent double freeing. */
108 static AviSynthLibrary avs_library;
109 static int avs_atexit_called = 0;
110
111 /* Linked list of AviSynthContexts. An atexit handler destroys this list. */
112 static AviSynthContext *avs_ctx_list = NULL;
113
114 static av_cold void avisynth_atexit_handler(void);
115
116 static av_cold int avisynth_load_library(void)
117 {
118 avs_library.library = LoadLibrary(AVISYNTH_LIB);
119 if (!avs_library.library)
120 return AVERROR_UNKNOWN;
121
122 #define LOAD_AVS_FUNC(name, continue_on_fail) \
123 avs_library.name = \
124 (void *)GetProcAddress(avs_library.library, #name); \
125 if (!continue_on_fail && !avs_library.name) \
126 goto fail;
127
128 LOAD_AVS_FUNC(avs_bit_blt, 0);
129 LOAD_AVS_FUNC(avs_clip_get_error, 0);
130 LOAD_AVS_FUNC(avs_create_script_environment, 0);
131 LOAD_AVS_FUNC(avs_delete_script_environment, 0);
132 LOAD_AVS_FUNC(avs_get_audio, 0);
133 LOAD_AVS_FUNC(avs_get_error, 1); // New to AviSynth 2.6
134 LOAD_AVS_FUNC(avs_get_frame, 0);
135 LOAD_AVS_FUNC(avs_get_version, 0);
136 LOAD_AVS_FUNC(avs_get_video_info, 0);
137 LOAD_AVS_FUNC(avs_invoke, 0);
138 LOAD_AVS_FUNC(avs_release_clip, 0);
139 LOAD_AVS_FUNC(avs_release_value, 0);
140 LOAD_AVS_FUNC(avs_release_video_frame, 0);
141 LOAD_AVS_FUNC(avs_take_clip, 0);
142 #ifdef USING_AVISYNTH
143 LOAD_AVS_FUNC(avs_bits_per_pixel, 1);
144 LOAD_AVS_FUNC(avs_get_height_p, 1);
145 LOAD_AVS_FUNC(avs_get_pitch_p, 1);
146 LOAD_AVS_FUNC(avs_get_read_ptr_p, 1);
147 LOAD_AVS_FUNC(avs_get_row_size_p, 1);
148 LOAD_AVS_FUNC(avs_is_yv24, 1);
149 LOAD_AVS_FUNC(avs_is_yv16, 1);
150 LOAD_AVS_FUNC(avs_is_yv411, 1);
151 LOAD_AVS_FUNC(avs_is_y8, 1);
152 #endif
153 #undef LOAD_AVS_FUNC
154
155 atexit(avisynth_atexit_handler);
156 return 0;
157
158 fail:
159 FreeLibrary(avs_library.library);
160 return AVERROR_UNKNOWN;
161 }
162
163 /* Note that avisynth_context_create and avisynth_context_destroy
164 * do not allocate or free the actual context! That is taken care of
165 * by libavformat. */
166 static av_cold int avisynth_context_create(AVFormatContext *s)
167 {
168 AviSynthContext *avs = s->priv_data;
169 int ret;
170
171 if (!avs_library.library)
172 if (ret = avisynth_load_library())
173 return ret;
174
175 avs->env = avs_library.avs_create_script_environment(3);
176 if (avs_library.avs_get_error) {
177 const char *error = avs_library.avs_get_error(avs->env);
178 if (error) {
179 av_log(s, AV_LOG_ERROR, "%s\n", error);
180 return AVERROR_UNKNOWN;
181 }
182 }
183
184 if (!avs_ctx_list) {
185 avs_ctx_list = avs;
186 } else {
187 avs->next = avs_ctx_list;
188 avs_ctx_list = avs;
189 }
190
191 return 0;
192 }
193
194 static av_cold void avisynth_context_destroy(AviSynthContext *avs)
195 {
196 if (avs_atexit_called)
197 return;
198
199 if (avs == avs_ctx_list) {
200 avs_ctx_list = avs->next;
201 } else {
202 AviSynthContext *prev = avs_ctx_list;
203 while (prev->next != avs)
204 prev = prev->next;
205 prev->next = avs->next;
206 }
207
208 if (avs->clip) {
209 avs_library.avs_release_clip(avs->clip);
210 avs->clip = NULL;
211 }
212 if (avs->env) {
213 avs_library.avs_delete_script_environment(avs->env);
214 avs->env = NULL;
215 }
216 }
217
218 static av_cold void avisynth_atexit_handler(void)
219 {
220 AviSynthContext *avs = avs_ctx_list;
221
222 while (avs) {
223 AviSynthContext *next = avs->next;
224 avisynth_context_destroy(avs);
225 avs = next;
226 }
227 FreeLibrary(avs_library.library);
228
229 avs_atexit_called = 1;
230 }
231
232 /* Create AVStream from audio and video data. */
233 static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
234 {
235 AviSynthContext *avs = s->priv_data;
236 int planar = 0; // 0: packed, 1: YUV, 2: Y8
237
238 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
239 st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
240 st->codec->width = avs->vi->width;
241 st->codec->height = avs->vi->height;
242
243 st->time_base = (AVRational) { avs->vi->fps_denominator,
244 avs->vi->fps_numerator };
245 st->avg_frame_rate = (AVRational) { avs->vi->fps_numerator,
246 avs->vi->fps_denominator };
247 st->start_time = 0;
248 st->duration = avs->vi->num_frames;
249 st->nb_frames = avs->vi->num_frames;
250
251 switch (avs->vi->pixel_type) {
252 #ifdef USING_AVISYNTH
253 case AVS_CS_YV24:
254 st->codec->pix_fmt = AV_PIX_FMT_YUV444P;
255 planar = 1;
256 break;
257 case AVS_CS_YV16:
258 st->codec->pix_fmt = AV_PIX_FMT_YUV422P;
259 planar = 1;
260 break;
261 case AVS_CS_YV411:
262 st->codec->pix_fmt = AV_PIX_FMT_YUV411P;
263 planar = 1;
264 break;
265 case AVS_CS_Y8:
266 st->codec->pix_fmt = AV_PIX_FMT_GRAY8;
267 planar = 2;
268 break;
269 #endif
270 case AVS_CS_BGR24:
271 st->codec->pix_fmt = AV_PIX_FMT_BGR24;
272 break;
273 case AVS_CS_BGR32:
274 st->codec->pix_fmt = AV_PIX_FMT_RGB32;
275 break;
276 case AVS_CS_YUY2:
277 st->codec->pix_fmt = AV_PIX_FMT_YUYV422;
278 break;
279 case AVS_CS_YV12:
280 st->codec->pix_fmt = AV_PIX_FMT_YUV420P;
281 planar = 1;
282 break;
283 case AVS_CS_I420: // Is this even used anywhere?
284 st->codec->pix_fmt = AV_PIX_FMT_YUV420P;
285 planar = 1;
286 break;
287 default:
288 av_log(s, AV_LOG_ERROR,
289 "unknown AviSynth colorspace %d\n", avs->vi->pixel_type);
290 avs->error = 1;
291 return AVERROR_UNKNOWN;
292 }
293
294 switch (planar) {
295 case 2: // Y8
296 avs->n_planes = 1;
297 avs->planes = avs_planes_grey;
298 break;
299 case 1: // YUV
300 avs->n_planes = 3;
301 avs->planes = avs_planes_yuv;
302 break;
303 default:
304 avs->n_planes = 1;
305 avs->planes = avs_planes_packed;
306 }
307 return 0;
308 }
309
310 static int avisynth_create_stream_audio(AVFormatContext *s, AVStream *st)
311 {
312 AviSynthContext *avs = s->priv_data;
313
314 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
315 st->codec->sample_rate = avs->vi->audio_samples_per_second;
316 st->codec->channels = avs->vi->nchannels;
317 st->time_base = (AVRational) { 1,
318 avs->vi->audio_samples_per_second };
319 st->duration = avs->vi->num_audio_samples;
320
321 switch (avs->vi->sample_type) {
322 case AVS_SAMPLE_INT8:
323 st->codec->codec_id = AV_CODEC_ID_PCM_U8;
324 break;
325 case AVS_SAMPLE_INT16:
326 st->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
327 break;
328 case AVS_SAMPLE_INT24:
329 st->codec->codec_id = AV_CODEC_ID_PCM_S24LE;
330 break;
331 case AVS_SAMPLE_INT32:
332 st->codec->codec_id = AV_CODEC_ID_PCM_S32LE;
333 break;
334 case AVS_SAMPLE_FLOAT:
335 st->codec->codec_id = AV_CODEC_ID_PCM_F32LE;
336 break;
337 default:
338 av_log(s, AV_LOG_ERROR,
339 "unknown AviSynth sample type %d\n", avs->vi->sample_type);
340 avs->error = 1;
341 return AVERROR_UNKNOWN;
342 }
343 return 0;
344 }
345
346 static int avisynth_create_stream(AVFormatContext *s)
347 {
348 AviSynthContext *avs = s->priv_data;
349 AVStream *st;
350 int ret;
351 int id = 0;
352
353 if (avs_has_video(avs->vi)) {
354 st = avformat_new_stream(s, NULL);
355 if (!st)
356 return AVERROR_UNKNOWN;
357 st->id = id++;
358 if (ret = avisynth_create_stream_video(s, st))
359 return ret;
360 }
361 if (avs_has_audio(avs->vi)) {
362 st = avformat_new_stream(s, NULL);
363 if (!st)
364 return AVERROR_UNKNOWN;
365 st->id = id++;
366 if (ret = avisynth_create_stream_audio(s, st))
367 return ret;
368 }
369 return 0;
370 }
371
372 static int avisynth_open_file(AVFormatContext *s)
373 {
374 AviSynthContext *avs = s->priv_data;
375 AVS_Value arg, val;
376 int ret;
377 #ifdef USING_AVISYNTH
378 char filename_ansi[MAX_PATH * 4];
379 wchar_t filename_wc[MAX_PATH * 4];
380 #endif
381
382 if (ret = avisynth_context_create(s))
383 return ret;
384
385 #ifdef USING_AVISYNTH
386 /* Convert UTF-8 to ANSI code page */
387 MultiByteToWideChar(CP_UTF8, 0, s->filename, -1, filename_wc, MAX_PATH * 4);
388 WideCharToMultiByte(CP_THREAD_ACP, 0, filename_wc, -1, filename_ansi,
389 MAX_PATH * 4, NULL, NULL);
390 arg = avs_new_value_string(filename_ansi);
391 #else
392 arg = avs_new_value_string(s->filename);
393 #endif
394 val = avs_library.avs_invoke(avs->env, "Import", arg, 0);
395 if (avs_is_error(val)) {
396 av_log(s, AV_LOG_ERROR, "%s\n", avs_as_error(val));
397 ret = AVERROR_UNKNOWN;
398 goto fail;
399 }
400 if (!avs_is_clip(val)) {
401 av_log(s, AV_LOG_ERROR, "AviSynth script did not return a clip\n");
402 ret = AVERROR_UNKNOWN;
403 goto fail;
404 }
405
406 avs->clip = avs_library.avs_take_clip(val, avs->env);
407 avs->vi = avs_library.avs_get_video_info(avs->clip);
408
409 #ifdef USING_AVISYNTH
410 /* On Windows, libav supports AviSynth interface version 6 or higher.
411 * This includes AviSynth 2.6 RC1 or higher, and AviSynth+ r1718 or higher,
412 * and excludes 2.5 and the 2.6 alphas. Since AvxSynth identifies itself
413 * as interface version 3 like 2.5.8, this needs to be special-cased. */
414
415 if (avs_library.avs_get_version(avs->clip) < 6) {
416 av_log(s, AV_LOG_ERROR,
417 "AviSynth version is too old. Please upgrade to either AviSynth 2.6 >= RC1 or AviSynth+ >= r1718.\n");
418 ret = AVERROR_UNKNOWN;
419 goto fail;
420 }
421 #endif
422
423 /* Release the AVS_Value as it will go out of scope. */
424 avs_library.avs_release_value(val);
425
426 if (ret = avisynth_create_stream(s))
427 goto fail;
428
429 return 0;
430
431 fail:
432 avisynth_context_destroy(avs);
433 return ret;
434 }
435
436 static void avisynth_next_stream(AVFormatContext *s, AVStream **st,
437 AVPacket *pkt, int *discard)
438 {
439 AviSynthContext *avs = s->priv_data;
440
441 avs->curr_stream++;
442 avs->curr_stream %= s->nb_streams;
443
444 *st = s->streams[avs->curr_stream];
445 if ((*st)->discard == AVDISCARD_ALL)
446 *discard = 1;
447 else
448 *discard = 0;
449
450 return;
451 }
452
453 /* Copy AviSynth clip data into an AVPacket. */
454 static int avisynth_read_packet_video(AVFormatContext *s, AVPacket *pkt,
455 int discard)
456 {
457 AviSynthContext *avs = s->priv_data;
458 AVS_VideoFrame *frame;
459 unsigned char *dst_p;
460 const unsigned char *src_p;
461 int n, i, plane, rowsize, planeheight, pitch, bits;
462 const char *error;
463
464 if (avs->curr_frame >= avs->vi->num_frames)
465 return AVERROR_EOF;
466
467 /* This must happen even if the stream is discarded to prevent desync. */
468 n = avs->curr_frame++;
469 if (discard)
470 return 0;
471
472 #ifdef USING_AVISYNTH
473 /* Define the bpp values for the new AviSynth 2.6 colorspaces.
474 * Since AvxSynth doesn't have these functions, special-case
475 * it in order to avoid implicit declaration errors. */
476
477 if (avs_library.avs_is_yv24(avs->vi))
478 bits = 24;
479 else if (avs_library.avs_is_yv16(avs->vi))
480 bits = 16;
481 else if (avs_library.avs_is_yv411(avs->vi))
482 bits = 12;
483 else if (avs_library.avs_is_y8(avs->vi))
484 bits = 8;
485 else
486 bits = avs_library.avs_bits_per_pixel(avs->vi);
487 #else
488 bits = avs_bits_per_pixel(avs->vi);
489 #endif
490
491 /* Without the cast to int64_t, calculation overflows at about 9k x 9k
492 * resolution. */
493 pkt->size = (((int64_t)avs->vi->width *
494 (int64_t)avs->vi->height) * bits) / 8;
495 if (!pkt->size)
496 return AVERROR_UNKNOWN;
497
498 if (av_new_packet(pkt, pkt->size) < 0)
499 return AVERROR(ENOMEM);
500
501 pkt->pts = n;
502 pkt->dts = n;
503 pkt->duration = 1;
504 pkt->stream_index = avs->curr_stream;
505
506 frame = avs_library.avs_get_frame(avs->clip, n);
507 error = avs_library.avs_clip_get_error(avs->clip);
508 if (error) {
509 av_log(s, AV_LOG_ERROR, "%s\n", error);
510 avs->error = 1;
511 av_packet_unref(pkt);
512 return AVERROR_UNKNOWN;
513 }
514
515 dst_p = pkt->data;
516 for (i = 0; i < avs->n_planes; i++) {
517 plane = avs->planes[i];
518 #ifdef USING_AVISYNTH
519 src_p = avs_library.avs_get_read_ptr_p(frame, plane);
520 pitch = avs_library.avs_get_pitch_p(frame, plane);
521
522 rowsize = avs_library.avs_get_row_size_p(frame, plane);
523 planeheight = avs_library.avs_get_height_p(frame, plane);
524 #else
525 src_p = avs_get_read_ptr_p(frame, plane);
526 pitch = avs_get_pitch_p(frame, plane);
527
528 rowsize = avs_get_row_size_p(frame, plane);
529 planeheight = avs_get_height_p(frame, plane);
530 #endif
531
532 /* Flip RGB video. */
533 if (avs_is_rgb24(avs->vi) || avs_is_rgb(avs->vi)) {
534 src_p = src_p + (planeheight - 1) * pitch;
535 pitch = -pitch;
536 }
537
538 avs_library.avs_bit_blt(avs->env, dst_p, rowsize, src_p, pitch,
539 rowsize, planeheight);
540 dst_p += rowsize * planeheight;
541 }
542
543 avs_library.avs_release_video_frame(frame);
544 return 0;
545 }
546
547 static int avisynth_read_packet_audio(AVFormatContext *s, AVPacket *pkt,
548 int discard)
549 {
550 AviSynthContext *avs = s->priv_data;
551 AVRational fps, samplerate;
552 int samples;
553 int64_t n;
554 const char *error;
555
556 if (avs->curr_sample >= avs->vi->num_audio_samples)
557 return AVERROR_EOF;
558
559 fps.num = avs->vi->fps_numerator;
560 fps.den = avs->vi->fps_denominator;
561 samplerate.num = avs->vi->audio_samples_per_second;
562 samplerate.den = 1;
563
564 if (avs_has_video(avs->vi)) {
565 if (avs->curr_frame < avs->vi->num_frames)
566 samples = av_rescale_q(avs->curr_frame, samplerate, fps) -
567 avs->curr_sample;
568 else
569 samples = av_rescale_q(1, samplerate, fps);
570 } else {
571 samples = 1000;
572 }
573
574 /* After seeking, audio may catch up with video. */
575 if (samples <= 0) {
576 pkt->size = 0;
577 pkt->data = NULL;
578 return 0;
579 }
580
581 if (avs->curr_sample + samples > avs->vi->num_audio_samples)
582 samples = avs->vi->num_audio_samples - avs->curr_sample;
583
584 /* This must happen even if the stream is discarded to prevent desync. */
585 n = avs->curr_sample;
586 avs->curr_sample += samples;
587 if (discard)
588 return 0;
589
590 pkt->size = avs_bytes_per_channel_sample(avs->vi) *
591 samples * avs->vi->nchannels;
592 if (!pkt->size)
593 return AVERROR_UNKNOWN;
594
595 if (av_new_packet(pkt, pkt->size) < 0)
596 return AVERROR(ENOMEM);
597
598 pkt->pts = n;
599 pkt->dts = n;
600 pkt->duration = samples;
601 pkt->stream_index = avs->curr_stream;
602
603 avs_library.avs_get_audio(avs->clip, pkt->data, n, samples);
604 error = avs_library.avs_clip_get_error(avs->clip);
605 if (error) {
606 av_log(s, AV_LOG_ERROR, "%s\n", error);
607 avs->error = 1;
608 av_packet_unref(pkt);
609 return AVERROR_UNKNOWN;
610 }
611 return 0;
612 }
613
614 static av_cold int avisynth_read_header(AVFormatContext *s)
615 {
616 int ret;
617
618 // Calling library must implement a lock for thread-safe opens.
619 if (ret = avpriv_lock_avformat())
620 return ret;
621
622 if (ret = avisynth_open_file(s)) {
623 avpriv_unlock_avformat();
624 return ret;
625 }
626
627 avpriv_unlock_avformat();
628 return 0;
629 }
630
631 static int avisynth_read_packet(AVFormatContext *s, AVPacket *pkt)
632 {
633 AviSynthContext *avs = s->priv_data;
634 AVStream *st;
635 int discard = 0;
636 int ret;
637
638 if (avs->error)
639 return AVERROR_UNKNOWN;
640
641 /* If either stream reaches EOF, try to read the other one before
642 * giving up. */
643 avisynth_next_stream(s, &st, pkt, &discard);
644 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
645 ret = avisynth_read_packet_video(s, pkt, discard);
646 if (ret == AVERROR_EOF && avs_has_audio(avs->vi)) {
647 avisynth_next_stream(s, &st, pkt, &discard);
648 return avisynth_read_packet_audio(s, pkt, discard);
649 }
650 } else {
651 ret = avisynth_read_packet_audio(s, pkt, discard);
652 if (ret == AVERROR_EOF && avs_has_video(avs->vi)) {
653 avisynth_next_stream(s, &st, pkt, &discard);
654 return avisynth_read_packet_video(s, pkt, discard);
655 }
656 }
657
658 return ret;
659 }
660
661 static av_cold int avisynth_read_close(AVFormatContext *s)
662 {
663 if (avpriv_lock_avformat())
664 return AVERROR_UNKNOWN;
665
666 avisynth_context_destroy(s->priv_data);
667 avpriv_unlock_avformat();
668 return 0;
669 }
670
671 static int avisynth_read_seek(AVFormatContext *s, int stream_index,
672 int64_t timestamp, int flags)
673 {
674 AviSynthContext *avs = s->priv_data;
675 AVStream *st;
676 AVRational fps, samplerate;
677
678 if (avs->error)
679 return AVERROR_UNKNOWN;
680
681 fps = (AVRational) { avs->vi->fps_numerator,
682 avs->vi->fps_denominator };
683 samplerate = (AVRational) { avs->vi->audio_samples_per_second, 1 };
684
685 st = s->streams[stream_index];
686 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
687 /* AviSynth frame counts are signed int. */
688 if ((timestamp >= avs->vi->num_frames) ||
689 (timestamp > INT_MAX) ||
690 (timestamp < 0))
691 return AVERROR_EOF;
692 avs->curr_frame = timestamp;
693 if (avs_has_audio(avs->vi))
694 avs->curr_sample = av_rescale_q(timestamp, samplerate, fps);
695 } else {
696 if ((timestamp >= avs->vi->num_audio_samples) || (timestamp < 0))
697 return AVERROR_EOF;
698 /* Force frame granularity for seeking. */
699 if (avs_has_video(avs->vi)) {
700 avs->curr_frame = av_rescale_q(timestamp, fps, samplerate);
701 avs->curr_sample = av_rescale_q(avs->curr_frame, samplerate, fps);
702 } else {
703 avs->curr_sample = timestamp;
704 }
705 }
706
707 return 0;
708 }
709
710 AVInputFormat ff_avisynth_demuxer = {
711 .name = "avisynth",
712 .long_name = NULL_IF_CONFIG_SMALL("AviSynth script"),
713 .priv_data_size = sizeof(AviSynthContext),
714 .read_header = avisynth_read_header,
715 .read_packet = avisynth_read_packet,
716 .read_close = avisynth_read_close,
717 .read_seek = avisynth_read_seek,
718 .extensions = "avs",
719 };