305fda6e76e6e026261c9e3fadc85a6780a0c90a
[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
35 * @author Clemens Fruhwirth <clemens@endorphin.org>
36 * @author Edouard Gomez <ed.gomez@free.fr>
37 */
38
39 #include "config.h"
40 #include "libavformat/avformat.h"
41 #include "libavformat/internal.h"
42 #include "libavutil/log.h"
43 #include "libavutil/opt.h"
44 #include "libavutil/parseutils.h"
45 #include <time.h>
46 #include <X11/X.h>
47 #include <X11/Xlib.h>
48 #include <X11/Xlibint.h>
49 #include <X11/Xproto.h>
50 #include <X11/Xutil.h>
51 #include <sys/shm.h>
52 #include <X11/extensions/shape.h>
53 #include <X11/extensions/XShm.h>
54 #include <X11/extensions/Xfixes.h>
55
56 /**
57 * X11 Device Demuxer context
58 */
59 struct x11_grab
60 {
61 const AVClass *class; /**< Class for private options. */
62 int frame_size; /**< Size in bytes of a grabbed frame */
63 AVRational time_base; /**< Time base */
64 int64_t time_frame; /**< Current time */
65
66 char *video_size; /**< String describing video size, set by a private option. */
67 int height; /**< Height of the grab frame */
68 int width; /**< Width of the grab frame */
69 int x_off; /**< Horizontal top-left corner coordinate */
70 int y_off; /**< Vertical top-left corner coordinate */
71
72 Display *dpy; /**< X11 display from which x11grab grabs frames */
73 XImage *image; /**< X11 image holding the grab */
74 int use_shm; /**< !0 when using XShm extension */
75 XShmSegmentInfo shminfo; /**< When using XShm, keeps track of XShm infos */
76 int draw_mouse; /**< Set by a private option. */
77 int follow_mouse; /**< Set by a private option. */
78 int show_region; /**< set by a private option. */
79 char *framerate; /**< Set by a private option. */
80
81 Window region_win; /**< This is used by show_region option. */
82 };
83
84 #define REGION_WIN_BORDER 3
85 /**
86 * Draw grabbing region window
87 *
88 * @param s x11_grab context
89 */
90 static void
91 x11grab_draw_region_win(struct x11_grab *s)
92 {
93 Display *dpy = s->dpy;
94 int screen;
95 Window win = s->region_win;
96 GC gc;
97
98 screen = DefaultScreen(dpy);
99 gc = XCreateGC(dpy, win, 0, 0);
100 XSetForeground(dpy, gc, WhitePixel(dpy, screen));
101 XSetBackground(dpy, gc, BlackPixel(dpy, screen));
102 XSetLineAttributes(dpy, gc, REGION_WIN_BORDER, LineDoubleDash, 0, 0);
103 XDrawRectangle(dpy, win, gc,
104 1, 1,
105 (s->width + REGION_WIN_BORDER * 2) - 1 * 2 - 1,
106 (s->height + REGION_WIN_BORDER * 2) - 1 * 2 - 1);
107 XFreeGC(dpy, gc);
108 }
109
110 /**
111 * Initialize grabbing region window
112 *
113 * @param s x11_grab context
114 */
115 static void
116 x11grab_region_win_init(struct x11_grab *s)
117 {
118 Display *dpy = s->dpy;
119 int screen;
120 XSetWindowAttributes attribs;
121 XRectangle rect;
122
123 screen = DefaultScreen(dpy);
124 attribs.override_redirect = True;
125 s->region_win = XCreateWindow(dpy, RootWindow(dpy, screen),
126 s->x_off - REGION_WIN_BORDER,
127 s->y_off - REGION_WIN_BORDER,
128 s->width + REGION_WIN_BORDER * 2,
129 s->height + REGION_WIN_BORDER * 2,
130 0, CopyFromParent,
131 InputOutput, CopyFromParent,
132 CWOverrideRedirect, &attribs);
133 rect.x = 0;
134 rect.y = 0;
135 rect.width = s->width;
136 rect.height = s->height;
137 XShapeCombineRectangles(dpy, s->region_win,
138 ShapeBounding, REGION_WIN_BORDER, REGION_WIN_BORDER,
139 &rect, 1, ShapeSubtract, 0);
140 XMapWindow(dpy, s->region_win);
141 XSelectInput(dpy, s->region_win, ExposureMask | StructureNotifyMask);
142 x11grab_draw_region_win(s);
143 }
144
145 /**
146 * Initialize the x11 grab device demuxer (public device demuxer API).
147 *
148 * @param s1 Context from avformat core
149 * @return <ul>
150 * <li>AVERROR(ENOMEM) no memory left</li>
151 * <li>AVERROR(EIO) other failure case</li>
152 * <li>0 success</li>
153 * </ul>
154 */
155 static int
156 x11grab_read_header(AVFormatContext *s1)
157 {
158 struct x11_grab *x11grab = s1->priv_data;
159 Display *dpy;
160 AVStream *st = NULL;
161 enum PixelFormat input_pixfmt;
162 XImage *image;
163 int x_off = 0;
164 int y_off = 0;
165 int screen;
166 int use_shm;
167 char *param, *offset;
168 int ret = 0;
169 AVRational framerate;
170
171 param = av_strdup(s1->filename);
172 offset = strchr(param, '+');
173 if (offset) {
174 sscanf(offset, "%d,%d", &x_off, &y_off);
175 x11grab->draw_mouse = !strstr(offset, "nomouse");
176 *offset= 0;
177 }
178
179 if ((ret = av_parse_video_size(&x11grab->width, &x11grab->height, x11grab->video_size)) < 0) {
180 av_log(s1, AV_LOG_ERROR, "Couldn't parse video size.\n");
181 goto out;
182 }
183 if ((ret = av_parse_video_rate(&framerate, x11grab->framerate)) < 0) {
184 av_log(s1, AV_LOG_ERROR, "Could not parse framerate: %s.\n", x11grab->framerate);
185 goto out;
186 }
187 av_log(s1, AV_LOG_INFO, "device: %s -> display: %s x: %d y: %d width: %d height: %d\n",
188 s1->filename, param, x_off, y_off, x11grab->width, x11grab->height);
189
190 dpy = XOpenDisplay(param);
191 if(!dpy) {
192 av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
193 ret = AVERROR(EIO);
194 goto out;
195 }
196
197 st = avformat_new_stream(s1, NULL);
198 if (!st) {
199 ret = AVERROR(ENOMEM);
200 goto out;
201 }
202 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
203
204 screen = DefaultScreen(dpy);
205
206 if (x11grab->follow_mouse) {
207 int screen_w, screen_h;
208 Window w;
209
210 screen_w = DisplayWidth(dpy, screen);
211 screen_h = DisplayHeight(dpy, screen);
212 XQueryPointer(dpy, RootWindow(dpy, screen), &w, &w, &x_off, &y_off, &ret, &ret, &ret);
213 x_off -= x11grab->width / 2;
214 y_off -= x11grab->height / 2;
215 x_off = FFMIN(FFMAX(x_off, 0), screen_w - x11grab->width);
216 y_off = FFMIN(FFMAX(y_off, 0), screen_h - x11grab->height);
217 av_log(s1, AV_LOG_INFO, "followmouse is enabled, resetting grabbing region to x: %d y: %d\n", x_off, y_off);
218 }
219
220 use_shm = XShmQueryExtension(dpy);
221 av_log(s1, AV_LOG_INFO, "shared memory extension %s found\n", use_shm ? "" : "not");
222
223 if(use_shm) {
224 int scr = XDefaultScreen(dpy);
225 image = XShmCreateImage(dpy,
226 DefaultVisual(dpy, scr),
227 DefaultDepth(dpy, scr),
228 ZPixmap,
229 NULL,
230 &x11grab->shminfo,
231 x11grab->width, x11grab->height);
232 x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
233 image->bytes_per_line * image->height,
234 IPC_CREAT|0777);
235 if (x11grab->shminfo.shmid == -1) {
236 av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
237 ret = AVERROR(ENOMEM);
238 goto out;
239 }
240 x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
241 x11grab->shminfo.readOnly = False;
242
243 if (!XShmAttach(dpy, &x11grab->shminfo)) {
244 av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
245 /* needs some better error subroutine :) */
246 ret = AVERROR(EIO);
247 goto out;
248 }
249 } else {
250 image = XGetImage(dpy, RootWindow(dpy, screen),
251 x_off,y_off,
252 x11grab->width, x11grab->height,
253 AllPlanes, ZPixmap);
254 }
255
256 switch (image->bits_per_pixel) {
257 case 8:
258 av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
259 input_pixfmt = PIX_FMT_PAL8;
260 break;
261 case 16:
262 if ( image->red_mask == 0xf800 &&
263 image->green_mask == 0x07e0 &&
264 image->blue_mask == 0x001f ) {
265 av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
266 input_pixfmt = PIX_FMT_RGB565;
267 } else if (image->red_mask == 0x7c00 &&
268 image->green_mask == 0x03e0 &&
269 image->blue_mask == 0x001f ) {
270 av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
271 input_pixfmt = PIX_FMT_RGB555;
272 } else {
273 av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
274 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);
275 ret = AVERROR(EIO);
276 goto out;
277 }
278 break;
279 case 24:
280 if ( image->red_mask == 0xff0000 &&
281 image->green_mask == 0x00ff00 &&
282 image->blue_mask == 0x0000ff ) {
283 input_pixfmt = PIX_FMT_BGR24;
284 } else if ( image->red_mask == 0x0000ff &&
285 image->green_mask == 0x00ff00 &&
286 image->blue_mask == 0xff0000 ) {
287 input_pixfmt = PIX_FMT_RGB24;
288 } else {
289 av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
290 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);
291 ret = AVERROR(EIO);
292 goto out;
293 }
294 break;
295 case 32:
296 input_pixfmt = PIX_FMT_RGB32;
297 break;
298 default:
299 av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
300 ret = AVERROR(EINVAL);
301 goto out;
302 }
303
304 x11grab->frame_size = x11grab->width * x11grab->height * image->bits_per_pixel/8;
305 x11grab->dpy = dpy;
306 x11grab->time_base = (AVRational){framerate.den, framerate.num};
307 x11grab->time_frame = av_gettime() / av_q2d(x11grab->time_base);
308 x11grab->x_off = x_off;
309 x11grab->y_off = y_off;
310 x11grab->image = image;
311 x11grab->use_shm = use_shm;
312
313 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
314 st->codec->codec_id = CODEC_ID_RAWVIDEO;
315 st->codec->width = x11grab->width;
316 st->codec->height = x11grab->height;
317 st->codec->pix_fmt = input_pixfmt;
318 st->codec->time_base = x11grab->time_base;
319 st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(x11grab->time_base) * 8;
320
321 out:
322 return ret;
323 }
324
325 /**
326 * Paint a mouse pointer in an X11 image.
327 *
328 * @param image image to paint the mouse pointer to
329 * @param s context used to retrieve original grabbing rectangle
330 * coordinates
331 */
332 static void
333 paint_mouse_pointer(XImage *image, struct x11_grab *s)
334 {
335 int x_off = s->x_off;
336 int y_off = s->y_off;
337 int width = s->width;
338 int height = s->height;
339 Display *dpy = s->dpy;
340 XFixesCursorImage *xcim;
341 int x, y;
342 int line, column;
343 int to_line, to_column;
344 int pixstride = image->bits_per_pixel >> 3;
345 /* Warning: in its insanity, xlib provides unsigned image data through a
346 * char* pointer, so we have to make it uint8_t to make things not break.
347 * Anyone who performs further investigation of the xlib API likely risks
348 * permanent brain damage. */
349 uint8_t *pix = image->data;
350
351 /* Code doesn't currently support 16-bit or PAL8 */
352 if (image->bits_per_pixel != 24 && image->bits_per_pixel != 32)
353 return;
354
355 xcim = XFixesGetCursorImage(dpy);
356
357 x = xcim->x - xcim->xhot;
358 y = xcim->y - xcim->yhot;
359
360 to_line = FFMIN((y + xcim->height), (height + y_off));
361 to_column = FFMIN((x + xcim->width), (width + x_off));
362
363 for (line = FFMAX(y, y_off); line < to_line; line++) {
364 for (column = FFMAX(x, x_off); column < to_column; column++) {
365 int xcim_addr = (line - y) * xcim->width + column - x;
366 int image_addr = ((line - y_off) * width + column - x_off) * pixstride;
367 int r = (uint8_t)(xcim->pixels[xcim_addr] >> 0);
368 int g = (uint8_t)(xcim->pixels[xcim_addr] >> 8);
369 int b = (uint8_t)(xcim->pixels[xcim_addr] >> 16);
370 int a = (uint8_t)(xcim->pixels[xcim_addr] >> 24);
371
372 if (a == 255) {
373 pix[image_addr+0] = r;
374 pix[image_addr+1] = g;
375 pix[image_addr+2] = b;
376 } else if (a) {
377 /* pixel values from XFixesGetCursorImage come premultiplied by alpha */
378 pix[image_addr+0] = r + (pix[image_addr+0]*(255-a) + 255/2) / 255;
379 pix[image_addr+1] = g + (pix[image_addr+1]*(255-a) + 255/2) / 255;
380 pix[image_addr+2] = b + (pix[image_addr+2]*(255-a) + 255/2) / 255;
381 }
382 }
383 }
384
385 XFree(xcim);
386 xcim = NULL;
387 }
388
389
390 /**
391 * Read new data in the image structure.
392 *
393 * @param dpy X11 display to grab from
394 * @param d
395 * @param image Image where the grab will be put
396 * @param x Top-Left grabbing rectangle horizontal coordinate
397 * @param y Top-Left grabbing rectangle vertical coordinate
398 * @return 0 if error, !0 if successful
399 */
400 static int
401 xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
402 {
403 xGetImageReply rep;
404 xGetImageReq *req;
405 long nbytes;
406
407 if (!image) {
408 return 0;
409 }
410
411 LockDisplay(dpy);
412 GetReq(GetImage, req);
413
414 /* First set up the standard stuff in the request */
415 req->drawable = d;
416 req->x = x;
417 req->y = y;
418 req->width = image->width;
419 req->height = image->height;
420 req->planeMask = (unsigned int)AllPlanes;
421 req->format = ZPixmap;
422
423 if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
424 UnlockDisplay(dpy);
425 SyncHandle();
426 return 0;
427 }
428
429 nbytes = (long)rep.length << 2;
430 _XReadPad(dpy, image->data, nbytes);
431
432 UnlockDisplay(dpy);
433 SyncHandle();
434 return 1;
435 }
436
437 /**
438 * Grab a frame from x11 (public device demuxer API).
439 *
440 * @param s1 Context from avformat core
441 * @param pkt Packet holding the brabbed frame
442 * @return frame size in bytes
443 */
444 static int
445 x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
446 {
447 struct x11_grab *s = s1->priv_data;
448 Display *dpy = s->dpy;
449 XImage *image = s->image;
450 int x_off = s->x_off;
451 int y_off = s->y_off;
452
453 int screen;
454 Window root;
455 int follow_mouse = s->follow_mouse;
456
457 int64_t curtime, delay;
458 struct timespec ts;
459
460 /* Calculate the time of the next frame */
461 s->time_frame += INT64_C(1000000);
462
463 /* wait based on the frame rate */
464 for(;;) {
465 curtime = av_gettime();
466 delay = s->time_frame * av_q2d(s->time_base) - curtime;
467 if (delay <= 0) {
468 if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
469 s->time_frame += INT64_C(1000000);
470 }
471 break;
472 }
473 ts.tv_sec = delay / 1000000;
474 ts.tv_nsec = (delay % 1000000) * 1000;
475 nanosleep(&ts, NULL);
476 }
477
478 av_init_packet(pkt);
479 pkt->data = image->data;
480 pkt->size = s->frame_size;
481 pkt->pts = curtime;
482
483 screen = DefaultScreen(dpy);
484 root = RootWindow(dpy, screen);
485 if (follow_mouse) {
486 int screen_w, screen_h;
487 int pointer_x, pointer_y, _;
488 Window w;
489
490 screen_w = DisplayWidth(dpy, screen);
491 screen_h = DisplayHeight(dpy, screen);
492 XQueryPointer(dpy, root, &w, &w, &pointer_x, &pointer_y, &_, &_, &_);
493 if (follow_mouse == -1) {
494 // follow the mouse, put it at center of grabbing region
495 x_off += pointer_x - s->width / 2 - x_off;
496 y_off += pointer_y - s->height / 2 - y_off;
497 } else {
498 // follow the mouse, but only move the grabbing region when mouse
499 // reaches within certain pixels to the edge.
500 if (pointer_x > x_off + s->width - follow_mouse) {
501 x_off += pointer_x - (x_off + s->width - follow_mouse);
502 } else if (pointer_x < x_off + follow_mouse)
503 x_off -= (x_off + follow_mouse) - pointer_x;
504 if (pointer_y > y_off + s->height - follow_mouse) {
505 y_off += pointer_y - (y_off + s->height - follow_mouse);
506 } else if (pointer_y < y_off + follow_mouse)
507 y_off -= (y_off + follow_mouse) - pointer_y;
508 }
509 // adjust grabbing region position if it goes out of screen.
510 s->x_off = x_off = FFMIN(FFMAX(x_off, 0), screen_w - s->width);
511 s->y_off = y_off = FFMIN(FFMAX(y_off, 0), screen_h - s->height);
512
513 if (s->show_region && s->region_win)
514 XMoveWindow(dpy, s->region_win,
515 s->x_off - REGION_WIN_BORDER,
516 s->y_off - REGION_WIN_BORDER);
517 }
518
519 if (s->show_region) {
520 if (s->region_win) {
521 XEvent evt;
522 // clean up the events, and do the initinal draw or redraw.
523 for (evt.type = NoEventMask; XCheckMaskEvent(dpy, ExposureMask | StructureNotifyMask, &evt); );
524 if (evt.type)
525 x11grab_draw_region_win(s);
526 } else {
527 x11grab_region_win_init(s);
528 }
529 }
530
531 if(s->use_shm) {
532 if (!XShmGetImage(dpy, root, image, x_off, y_off, AllPlanes)) {
533 av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n");
534 }
535 } else {
536 if (!xget_zpixmap(dpy, root, image, x_off, y_off)) {
537 av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
538 }
539 }
540
541 if (s->draw_mouse) {
542 paint_mouse_pointer(image, s);
543 }
544
545 return s->frame_size;
546 }
547
548 /**
549 * Close x11 frame grabber (public device demuxer API).
550 *
551 * @param s1 Context from avformat core
552 * @return 0 success, !0 failure
553 */
554 static int
555 x11grab_read_close(AVFormatContext *s1)
556 {
557 struct x11_grab *x11grab = s1->priv_data;
558
559 /* Detach cleanly from shared mem */
560 if (x11grab->use_shm) {
561 XShmDetach(x11grab->dpy, &x11grab->shminfo);
562 shmdt(x11grab->shminfo.shmaddr);
563 shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
564 }
565
566 /* Destroy X11 image */
567 if (x11grab->image) {
568 XDestroyImage(x11grab->image);
569 x11grab->image = NULL;
570 }
571
572 if (x11grab->region_win) {
573 XDestroyWindow(x11grab->dpy, x11grab->region_win);
574 }
575
576 /* Free X11 display */
577 XCloseDisplay(x11grab->dpy);
578 return 0;
579 }
580
581 #define OFFSET(x) offsetof(struct x11_grab, x)
582 #define DEC AV_OPT_FLAG_DECODING_PARAM
583 static const AVOption options[] = {
584 { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = "vga"}, 0, 0, DEC },
585 { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "ntsc"}, 0, 0, DEC },
586 { "draw_mouse", "Draw the mouse pointer.", OFFSET(draw_mouse), AV_OPT_TYPE_INT, { 1 }, 0, 1, DEC },
587 { "follow_mouse", "Move the grabbing region when the mouse pointer reaches within specified amount of pixels to the edge of region.",
588 OFFSET(follow_mouse), AV_OPT_TYPE_INT, { 0 }, -1, INT_MAX, DEC, "follow_mouse" },
589 { "centered", "Keep the mouse pointer at the center of grabbing region when following.", 0, AV_OPT_TYPE_CONST, { -1 }, INT_MIN, INT_MAX, DEC, "follow_mouse" },
590 { "show_region", "Show the grabbing region.", OFFSET(show_region), AV_OPT_TYPE_INT, { 0 }, 0, 1, DEC },
591 { NULL },
592 };
593
594 static const AVClass x11_class = {
595 .class_name = "X11grab indev",
596 .item_name = av_default_item_name,
597 .option = options,
598 .version = LIBAVUTIL_VERSION_INT,
599 };
600
601 /** x11 grabber device demuxer declaration */
602 AVInputFormat ff_x11_grab_device_demuxer = {
603 .name = "x11grab",
604 .long_name = NULL_IF_CONFIG_SMALL("X11grab"),
605 .priv_data_size = sizeof(struct x11_grab),
606 .read_header = x11grab_read_header,
607 .read_packet = x11grab_read_packet,
608 .read_close = x11grab_read_close,
609 .flags = AVFMT_NOFILE,
610 .priv_class = &x11_class,
611 };