x11grab: add show_region AVOption.
[libav.git] / libavdevice / x11grab.c
1 /*
2 * X11 video grab interface
3 *
4 * This file is part of Libav.
5 *
6 * Libav integration:
7 * Copyright (C) 2006 Clemens Fruhwirth <clemens@endorphin.org>
8 * Edouard Gomez <ed.gomez@free.fr>
9 *
10 * This file contains code from grab.c:
11 * Copyright (c) 2000-2001 Fabrice Bellard
12 *
13 * This file contains code from the xvidcap project:
14 * Copyright (C) 1997-1998 Rasca, Berlin
15 * 2003-2004 Karl H. Beckers, Frankfurt
16 *
17 * Libav is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * Libav is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with Libav; if not, write to the Free Software
29 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 */
31
32 /**
33 * @file
34 * X11 frame device demuxer by Clemens Fruhwirth <clemens@endorphin.org>
35 * and Edouard Gomez <ed.gomez@free.fr>.
36 */
37
38 #include "config.h"
39 #include "libavformat/avformat.h"
40 #include "libavutil/log.h"
41 #include "libavutil/opt.h"
42 #include "libavutil/parseutils.h"
43 #include <time.h>
44 #include <X11/X.h>
45 #include <X11/Xlib.h>
46 #include <X11/Xlibint.h>
47 #include <X11/Xproto.h>
48 #include <X11/Xutil.h>
49 #include <sys/shm.h>
50 #include <X11/extensions/shape.h>
51 #include <X11/extensions/XShm.h>
52 #include <X11/extensions/Xfixes.h>
53
54 /**
55 * X11 Device Demuxer context
56 */
57 struct x11_grab
58 {
59 const AVClass *class; /**< Class for private options. */
60 int frame_size; /**< Size in bytes of a grabbed frame */
61 AVRational time_base; /**< Time base */
62 int64_t time_frame; /**< Current time */
63
64 char *video_size; /**< String describing video size, set by a private option. */
65 int height; /**< Height of the grab frame */
66 int width; /**< Width of the grab frame */
67 int x_off; /**< Horizontal top-left corner coordinate */
68 int y_off; /**< Vertical top-left corner coordinate */
69
70 Display *dpy; /**< X11 display from which x11grab grabs frames */
71 XImage *image; /**< X11 image holding the grab */
72 int use_shm; /**< !0 when using XShm extension */
73 XShmSegmentInfo shminfo; /**< When using XShm, keeps track of XShm infos */
74 int draw_mouse; /**< Set by a private option. */
75 int follow_mouse; /**< Set by a private option. */
76 int show_region; /**< set by a private option. */
77 char *framerate; /**< Set by a private option. */
78
79 Window region_win; /**< This is used by show_region option. */
80 };
81
82 #define REGION_WIN_BORDER 3
83 /**
84 * Draw grabbing region window
85 *
86 * @param s x11_grab context
87 */
88 static void
89 x11grab_draw_region_win(struct x11_grab *s)
90 {
91 Display *dpy = s->dpy;
92 int screen;
93 Window win = s->region_win;
94 GC gc;
95
96 screen = DefaultScreen(dpy);
97 gc = XCreateGC(dpy, win, 0, 0);
98 XSetForeground(dpy, gc, WhitePixel(dpy, screen));
99 XSetBackground(dpy, gc, BlackPixel(dpy, screen));
100 XSetLineAttributes(dpy, gc, REGION_WIN_BORDER, LineDoubleDash, 0, 0);
101 XDrawRectangle(dpy, win, gc,
102 1, 1,
103 (s->width + REGION_WIN_BORDER * 2) - 1 * 2 - 1,
104 (s->height + REGION_WIN_BORDER * 2) - 1 * 2 - 1);
105 XFreeGC(dpy, gc);
106 }
107
108 /**
109 * Initialize grabbing region window
110 *
111 * @param s x11_grab context
112 */
113 static void
114 x11grab_region_win_init(struct x11_grab *s)
115 {
116 Display *dpy = s->dpy;
117 int screen;
118 XSetWindowAttributes attribs;
119 XRectangle rect;
120
121 screen = DefaultScreen(dpy);
122 attribs.override_redirect = True;
123 s->region_win = XCreateWindow(dpy, RootWindow(dpy, screen),
124 s->x_off - REGION_WIN_BORDER,
125 s->y_off - REGION_WIN_BORDER,
126 s->width + REGION_WIN_BORDER * 2,
127 s->height + REGION_WIN_BORDER * 2,
128 0, CopyFromParent,
129 InputOutput, CopyFromParent,
130 CWOverrideRedirect, &attribs);
131 rect.x = 0;
132 rect.y = 0;
133 rect.width = s->width;
134 rect.height = s->height;
135 XShapeCombineRectangles(dpy, s->region_win,
136 ShapeBounding, REGION_WIN_BORDER, REGION_WIN_BORDER,
137 &rect, 1, ShapeSubtract, 0);
138 XMapWindow(dpy, s->region_win);
139 XSelectInput(dpy, s->region_win, ExposureMask | StructureNotifyMask);
140 x11grab_draw_region_win(s);
141 }
142
143 /**
144 * Initialize the x11 grab device demuxer (public device demuxer API).
145 *
146 * @param s1 Context from avformat core
147 * @param ap Parameters from avformat core
148 * @return <ul>
149 * <li>AVERROR(ENOMEM) no memory left</li>
150 * <li>AVERROR(EIO) other failure case</li>
151 * <li>0 success</li>
152 * </ul>
153 */
154 static int
155 x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
156 {
157 struct x11_grab *x11grab = s1->priv_data;
158 Display *dpy;
159 AVStream *st = NULL;
160 enum PixelFormat input_pixfmt;
161 XImage *image;
162 int x_off = 0;
163 int y_off = 0;
164 int screen;
165 int use_shm;
166 char *param, *offset;
167 int ret = 0;
168 AVRational framerate;
169
170 param = av_strdup(s1->filename);
171 offset = strchr(param, '+');
172 if (offset) {
173 sscanf(offset, "%d,%d", &x_off, &y_off);
174 x11grab->draw_mouse = !strstr(offset, "nomouse");
175 *offset= 0;
176 }
177
178 if ((ret = av_parse_video_size(&x11grab->width, &x11grab->height, x11grab->video_size)) < 0) {
179 av_log(s1, AV_LOG_ERROR, "Couldn't parse video size.\n");
180 goto out;
181 }
182 if ((ret = av_parse_video_rate(&framerate, x11grab->framerate)) < 0) {
183 av_log(s1, AV_LOG_ERROR, "Could not parse framerate: %s.\n", x11grab->framerate);
184 goto out;
185 }
186 #if FF_API_FORMAT_PARAMETERS
187 if (ap->width > 0)
188 x11grab->width = ap->width;
189 if (ap->height > 0)
190 x11grab->height = ap->height;
191 if (ap->time_base.num)
192 framerate = (AVRational){ap->time_base.den, ap->time_base.num};
193 #endif
194 av_log(s1, AV_LOG_INFO, "device: %s -> display: %s x: %d y: %d width: %d height: %d\n",
195 s1->filename, param, x_off, y_off, x11grab->width, x11grab->height);
196
197 dpy = XOpenDisplay(param);
198 if(!dpy) {
199 av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
200 ret = AVERROR(EIO);
201 goto out;
202 }
203
204 st = av_new_stream(s1, 0);
205 if (!st) {
206 ret = AVERROR(ENOMEM);
207 goto out;
208 }
209 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
210
211 screen = DefaultScreen(dpy);
212
213 if (x11grab->follow_mouse) {
214 int screen_w, screen_h;
215 Window w;
216
217 screen_w = DisplayWidth(dpy, screen);
218 screen_h = DisplayHeight(dpy, screen);
219 XQueryPointer(dpy, RootWindow(dpy, screen), &w, &w, &x_off, &y_off, &ret, &ret, &ret);
220 x_off -= x11grab->width / 2;
221 y_off -= x11grab->height / 2;
222 x_off = FFMIN(FFMAX(x_off, 0), screen_w - x11grab->width);
223 y_off = FFMIN(FFMAX(y_off, 0), screen_h - x11grab->height);
224 av_log(s1, AV_LOG_INFO, "followmouse is enabled, resetting grabbing region to x: %d y: %d\n", x_off, y_off);
225 }
226
227 use_shm = XShmQueryExtension(dpy);
228 av_log(s1, AV_LOG_INFO, "shared memory extension %s found\n", use_shm ? "" : "not");
229
230 if(use_shm) {
231 int scr = XDefaultScreen(dpy);
232 image = XShmCreateImage(dpy,
233 DefaultVisual(dpy, scr),
234 DefaultDepth(dpy, scr),
235 ZPixmap,
236 NULL,
237 &x11grab->shminfo,
238 x11grab->width, x11grab->height);
239 x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
240 image->bytes_per_line * image->height,
241 IPC_CREAT|0777);
242 if (x11grab->shminfo.shmid == -1) {
243 av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
244 ret = AVERROR(ENOMEM);
245 goto out;
246 }
247 x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
248 x11grab->shminfo.readOnly = False;
249
250 if (!XShmAttach(dpy, &x11grab->shminfo)) {
251 av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
252 /* needs some better error subroutine :) */
253 ret = AVERROR(EIO);
254 goto out;
255 }
256 } else {
257 image = XGetImage(dpy, RootWindow(dpy, screen),
258 x_off,y_off,
259 x11grab->width, x11grab->height,
260 AllPlanes, ZPixmap);
261 }
262
263 switch (image->bits_per_pixel) {
264 case 8:
265 av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
266 input_pixfmt = PIX_FMT_PAL8;
267 break;
268 case 16:
269 if ( image->red_mask == 0xf800 &&
270 image->green_mask == 0x07e0 &&
271 image->blue_mask == 0x001f ) {
272 av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
273 input_pixfmt = PIX_FMT_RGB565;
274 } else if (image->red_mask == 0x7c00 &&
275 image->green_mask == 0x03e0 &&
276 image->blue_mask == 0x001f ) {
277 av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
278 input_pixfmt = PIX_FMT_RGB555;
279 } else {
280 av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
281 av_log(s1, AV_LOG_ERROR, "color masks: r 0x%.6lx g 0x%.6lx b 0x%.6lx\n", image->red_mask, image->green_mask, image->blue_mask);
282 ret = AVERROR(EIO);
283 goto out;
284 }
285 break;
286 case 24:
287 if ( image->red_mask == 0xff0000 &&
288 image->green_mask == 0x00ff00 &&
289 image->blue_mask == 0x0000ff ) {
290 input_pixfmt = PIX_FMT_BGR24;
291 } else if ( image->red_mask == 0x0000ff &&
292 image->green_mask == 0x00ff00 &&
293 image->blue_mask == 0xff0000 ) {
294 input_pixfmt = PIX_FMT_RGB24;
295 } else {
296 av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
297 av_log(s1, AV_LOG_ERROR, "color masks: r 0x%.6lx g 0x%.6lx b 0x%.6lx\n", image->red_mask, image->green_mask, image->blue_mask);
298 ret = AVERROR(EIO);
299 goto out;
300 }
301 break;
302 case 32:
303 input_pixfmt = PIX_FMT_RGB32;
304 break;
305 default:
306 av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
307 ret = AVERROR(EINVAL);
308 goto out;
309 }
310
311 x11grab->frame_size = x11grab->width * x11grab->height * image->bits_per_pixel/8;
312 x11grab->dpy = dpy;
313 x11grab->time_base = (AVRational){framerate.den, framerate.num};
314 x11grab->time_frame = av_gettime() / av_q2d(x11grab->time_base);
315 x11grab->x_off = x_off;
316 x11grab->y_off = y_off;
317 x11grab->image = image;
318 x11grab->use_shm = use_shm;
319
320 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
321 st->codec->codec_id = CODEC_ID_RAWVIDEO;
322 st->codec->width = x11grab->width;
323 st->codec->height = x11grab->height;
324 st->codec->pix_fmt = input_pixfmt;
325 st->codec->time_base = x11grab->time_base;
326 st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(x11grab->time_base) * 8;
327
328 out:
329 return ret;
330 }
331
332 /**
333 * Paint a mouse pointer in an X11 image.
334 *
335 * @param image image to paint the mouse pointer to
336 * @param s context used to retrieve original grabbing rectangle
337 * coordinates
338 */
339 static void
340 paint_mouse_pointer(XImage *image, struct x11_grab *s)
341 {
342 int x_off = s->x_off;
343 int y_off = s->y_off;
344 int width = s->width;
345 int height = s->height;
346 Display *dpy = s->dpy;
347 XFixesCursorImage *xcim;
348 int x, y;
349 int line, column;
350 int to_line, to_column;
351 int pixstride = image->bits_per_pixel >> 3;
352 /* Warning: in its insanity, xlib provides unsigned image data through a
353 * char* pointer, so we have to make it uint8_t to make things not break.
354 * Anyone who performs further investigation of the xlib API likely risks
355 * permanent brain damage. */
356 uint8_t *pix = image->data;
357
358 /* Code doesn't currently support 16-bit or PAL8 */
359 if (image->bits_per_pixel != 24 && image->bits_per_pixel != 32)
360 return;
361
362 xcim = XFixesGetCursorImage(dpy);
363
364 x = xcim->x - xcim->xhot;
365 y = xcim->y - xcim->yhot;
366
367 to_line = FFMIN((y + xcim->height), (height + y_off));
368 to_column = FFMIN((x + xcim->width), (width + x_off));
369
370 for (line = FFMAX(y, y_off); line < to_line; line++) {
371 for (column = FFMAX(x, x_off); column < to_column; column++) {
372 int xcim_addr = (line - y) * xcim->width + column - x;
373 int image_addr = ((line - y_off) * width + column - x_off) * pixstride;
374 int r = (uint8_t)(xcim->pixels[xcim_addr] >> 0);
375 int g = (uint8_t)(xcim->pixels[xcim_addr] >> 8);
376 int b = (uint8_t)(xcim->pixels[xcim_addr] >> 16);
377 int a = (uint8_t)(xcim->pixels[xcim_addr] >> 24);
378
379 if (a == 255) {
380 pix[image_addr+0] = r;
381 pix[image_addr+1] = g;
382 pix[image_addr+2] = b;
383 } else if (a) {
384 /* pixel values from XFixesGetCursorImage come premultiplied by alpha */
385 pix[image_addr+0] = r + (pix[image_addr+0]*(255-a) + 255/2) / 255;
386 pix[image_addr+1] = g + (pix[image_addr+1]*(255-a) + 255/2) / 255;
387 pix[image_addr+2] = b + (pix[image_addr+2]*(255-a) + 255/2) / 255;
388 }
389 }
390 }
391
392 XFree(xcim);
393 xcim = NULL;
394 }
395
396
397 /**
398 * Read new data in the image structure.
399 *
400 * @param dpy X11 display to grab from
401 * @param d
402 * @param image Image where the grab will be put
403 * @param x Top-Left grabbing rectangle horizontal coordinate
404 * @param y Top-Left grabbing rectangle vertical coordinate
405 * @return 0 if error, !0 if successful
406 */
407 static int
408 xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
409 {
410 xGetImageReply rep;
411 xGetImageReq *req;
412 long nbytes;
413
414 if (!image) {
415 return 0;
416 }
417
418 LockDisplay(dpy);
419 GetReq(GetImage, req);
420
421 /* First set up the standard stuff in the request */
422 req->drawable = d;
423 req->x = x;
424 req->y = y;
425 req->width = image->width;
426 req->height = image->height;
427 req->planeMask = (unsigned int)AllPlanes;
428 req->format = ZPixmap;
429
430 if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
431 UnlockDisplay(dpy);
432 SyncHandle();
433 return 0;
434 }
435
436 nbytes = (long)rep.length << 2;
437 _XReadPad(dpy, image->data, nbytes);
438
439 UnlockDisplay(dpy);
440 SyncHandle();
441 return 1;
442 }
443
444 /**
445 * Grab a frame from x11 (public device demuxer API).
446 *
447 * @param s1 Context from avformat core
448 * @param pkt Packet holding the brabbed frame
449 * @return frame size in bytes
450 */
451 static int
452 x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
453 {
454 struct x11_grab *s = s1->priv_data;
455 Display *dpy = s->dpy;
456 XImage *image = s->image;
457 int x_off = s->x_off;
458 int y_off = s->y_off;
459
460 int screen;
461 Window root;
462 int follow_mouse = s->follow_mouse;
463
464 int64_t curtime, delay;
465 struct timespec ts;
466
467 /* Calculate the time of the next frame */
468 s->time_frame += INT64_C(1000000);
469
470 /* wait based on the frame rate */
471 for(;;) {
472 curtime = av_gettime();
473 delay = s->time_frame * av_q2d(s->time_base) - curtime;
474 if (delay <= 0) {
475 if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
476 s->time_frame += INT64_C(1000000);
477 }
478 break;
479 }
480 ts.tv_sec = delay / 1000000;
481 ts.tv_nsec = (delay % 1000000) * 1000;
482 nanosleep(&ts, NULL);
483 }
484
485 av_init_packet(pkt);
486 pkt->data = image->data;
487 pkt->size = s->frame_size;
488 pkt->pts = curtime;
489
490 screen = DefaultScreen(dpy);
491 root = RootWindow(dpy, screen);
492 if (follow_mouse) {
493 int screen_w, screen_h;
494 int pointer_x, pointer_y, _;
495 Window w;
496
497 screen_w = DisplayWidth(dpy, screen);
498 screen_h = DisplayHeight(dpy, screen);
499 XQueryPointer(dpy, root, &w, &w, &pointer_x, &pointer_y, &_, &_, &_);
500 if (follow_mouse == -1) {
501 // follow the mouse, put it at center of grabbing region
502 x_off += pointer_x - s->width / 2 - x_off;
503 y_off += pointer_y - s->height / 2 - y_off;
504 } else {
505 // follow the mouse, but only move the grabbing region when mouse
506 // reaches within certain pixels to the edge.
507 if (pointer_x > x_off + s->width - follow_mouse) {
508 x_off += pointer_x - (x_off + s->width - follow_mouse);
509 } else if (pointer_x < x_off + follow_mouse)
510 x_off -= (x_off + follow_mouse) - pointer_x;
511 if (pointer_y > y_off + s->height - follow_mouse) {
512 y_off += pointer_y - (y_off + s->height - follow_mouse);
513 } else if (pointer_y < y_off + follow_mouse)
514 y_off -= (y_off + follow_mouse) - pointer_y;
515 }
516 // adjust grabbing region position if it goes out of screen.
517 s->x_off = x_off = FFMIN(FFMAX(x_off, 0), screen_w - s->width);
518 s->y_off = y_off = FFMIN(FFMAX(y_off, 0), screen_h - s->height);
519
520 if (s->show_region && s->region_win)
521 XMoveWindow(dpy, s->region_win,
522 s->x_off - REGION_WIN_BORDER,
523 s->y_off - REGION_WIN_BORDER);
524 }
525
526 if (s->show_region) {
527 if (s->region_win) {
528 XEvent evt;
529 // clean up the events, and do the initinal draw or redraw.
530 for (evt.type = NoEventMask; XCheckMaskEvent(dpy, ExposureMask | StructureNotifyMask, &evt); );
531 if (evt.type)
532 x11grab_draw_region_win(s);
533 } else {
534 x11grab_region_win_init(s);
535 }
536 }
537
538 if(s->use_shm) {
539 if (!XShmGetImage(dpy, root, image, x_off, y_off, AllPlanes)) {
540 av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n");
541 }
542 } else {
543 if (!xget_zpixmap(dpy, root, image, x_off, y_off)) {
544 av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
545 }
546 }
547
548 if (s->draw_mouse) {
549 paint_mouse_pointer(image, s);
550 }
551
552 return s->frame_size;
553 }
554
555 /**
556 * Close x11 frame grabber (public device demuxer API).
557 *
558 * @param s1 Context from avformat core
559 * @return 0 success, !0 failure
560 */
561 static int
562 x11grab_read_close(AVFormatContext *s1)
563 {
564 struct x11_grab *x11grab = s1->priv_data;
565
566 /* Detach cleanly from shared mem */
567 if (x11grab->use_shm) {
568 XShmDetach(x11grab->dpy, &x11grab->shminfo);
569 shmdt(x11grab->shminfo.shmaddr);
570 shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
571 }
572
573 /* Destroy X11 image */
574 if (x11grab->image) {
575 XDestroyImage(x11grab->image);
576 x11grab->image = NULL;
577 }
578
579 if (x11grab->region_win) {
580 XDestroyWindow(x11grab->dpy, x11grab->region_win);
581 }
582
583 /* Free X11 display */
584 XCloseDisplay(x11grab->dpy);
585 return 0;
586 }
587
588 #define OFFSET(x) offsetof(struct x11_grab, x)
589 #define DEC AV_OPT_FLAG_DECODING_PARAM
590 static const AVOption options[] = {
591 { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), FF_OPT_TYPE_STRING, {.str = "vga"}, 0, 0, DEC },
592 { "framerate", "", OFFSET(framerate), FF_OPT_TYPE_STRING, {.str = "ntsc"}, 0, 0, DEC },
593 { "draw_mouse", "Draw the mouse pointer.", OFFSET(draw_mouse), FF_OPT_TYPE_INT, { 1 }, 0, 1, DEC },
594 { "follow_mouse", "Move the grabbing region when the mouse pointer reaches within specified amount of pixels to the edge of region.",
595 OFFSET(follow_mouse), FF_OPT_TYPE_INT, { 0 }, -1, INT_MAX, DEC, "follow_mouse" },
596 { "centered", "Keep the mouse pointer at the center of grabbing region when following.", 0, FF_OPT_TYPE_CONST, { -1 }, INT_MIN, INT_MAX, DEC, "follow_mouse" },
597 { "show_region", "Show the grabbing region.", OFFSET(show_region), FF_OPT_TYPE_INT, { 0 }, 0, 1, DEC },
598 { NULL },
599 };
600
601 static const AVClass x11_class = {
602 .class_name = "X11grab indev",
603 .item_name = av_default_item_name,
604 .option = options,
605 .version = LIBAVUTIL_VERSION_INT,
606 };
607
608 /** x11 grabber device demuxer declaration */
609 AVInputFormat ff_x11_grab_device_demuxer =
610 {
611 "x11grab",
612 NULL_IF_CONFIG_SMALL("X11grab"),
613 sizeof(struct x11_grab),
614 NULL,
615 x11grab_read_header,
616 x11grab_read_packet,
617 x11grab_read_close,
618 .flags = AVFMT_NOFILE,
619 .priv_class = &x11_class,
620 };