2 * X11 video grab interface
4 * This file is part of FFmpeg.
7 * Copyright (C) 2006 Clemens Fruhwirth <clemens@endorphin.org>
8 * Edouard Gomez <ed.gomez@free.fr>
10 * This file contains code from grab.c:
11 * Copyright (c) 2000-2001 Fabrice Bellard
13 * This file contains code from the xvidcap project:
14 * Copyright (C) 1997-1998 Rasca, Berlin
15 * 2003-2004 Karl H. Beckers, Frankfurt
17 * FFmpeg 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.
22 * FFmpeg 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.
27 * You should have received a copy of the GNU General Public License
28 * along with FFmpeg; if not, write to the Free Software
29 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
34 * X11 frame device demuxer by Clemens Fruhwirth <clemens@endorphin.org>
35 * and Edouard Gomez <ed.gomez@free.fr>.
38 #define _XOPEN_SOURCE 600
41 #include "libavformat/avformat.h"
45 #include <X11/Xlibint.h>
46 #include <X11/Xproto.h>
47 #include <X11/Xutil.h>
49 #include <X11/extensions/XShm.h>
50 #include <X11/extensions/Xfixes.h>
53 * X11 Device Demuxer context
57 int frame_size; /**< Size in bytes of a grabbed frame */
58 AVRational time_base; /**< Time base */
59 int64_t time_frame; /**< Current time */
61 int height; /**< Height of the grab frame */
62 int width; /**< Width of the grab frame */
63 int x_off; /**< Horizontal top-left corner coordinate */
64 int y_off; /**< Vertical top-left corner coordinate */
66 Display *dpy; /**< X11 display from which x11grab grabs frames */
67 XImage *image; /**< X11 image holding the grab */
68 int use_shm; /**< !0 when using XShm extension */
69 XShmSegmentInfo shminfo; /**< When using XShm, keeps track of XShm infos */
74 * Initialize the x11 grab device demuxer (public device demuxer API).
76 * @param s1 Context from avformat core
77 * @param ap Parameters from avformat core
79 * <li>AVERROR(ENOMEM) no memory left</li>
80 * <li>AVERROR(EIO) other failure case</li>
85 x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
87 struct x11_grab *x11grab = s1->priv_data;
90 enum PixelFormat input_pixfmt;
95 char *dpyname, *offset;
97 dpyname = av_strdup(s1->filename);
98 offset = strchr(dpyname, '+');
100 sscanf(offset, "%d,%d", &x_off, &y_off);
101 x11grab->nomouse= strstr(offset, "nomouse");
105 av_log(s1, AV_LOG_INFO, "device: %s -> display: %s x: %d y: %d width: %d height: %d\n", s1->filename, dpyname, x_off, y_off, ap->width, ap->height);
107 dpy = XOpenDisplay(dpyname);
110 av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
114 if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
115 av_log(s1, AV_LOG_ERROR, "AVParameters don't have video size and/or rate. Use -s and -r.\n");
119 st = av_new_stream(s1, 0);
121 return AVERROR(ENOMEM);
123 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
125 use_shm = XShmQueryExtension(dpy);
126 av_log(s1, AV_LOG_INFO, "shared memory extension%s found\n", use_shm ? "" : " not");
129 int scr = XDefaultScreen(dpy);
130 image = XShmCreateImage(dpy,
131 DefaultVisual(dpy, scr),
132 DefaultDepth(dpy, scr),
136 ap->width, ap->height);
137 x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
138 image->bytes_per_line * image->height,
140 if (x11grab->shminfo.shmid == -1) {
141 av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
142 return AVERROR(ENOMEM);
144 x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
145 x11grab->shminfo.readOnly = False;
147 if (!XShmAttach(dpy, &x11grab->shminfo)) {
148 av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
149 /* needs some better error subroutine :) */
153 image = XGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)),
155 ap->width,ap->height,
159 switch (image->bits_per_pixel) {
161 av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
162 input_pixfmt = PIX_FMT_PAL8;
165 if ( image->red_mask == 0xf800 &&
166 image->green_mask == 0x07e0 &&
167 image->blue_mask == 0x001f ) {
168 av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
169 input_pixfmt = PIX_FMT_RGB565;
170 } else if (image->red_mask == 0x7c00 &&
171 image->green_mask == 0x03e0 &&
172 image->blue_mask == 0x001f ) {
173 av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
174 input_pixfmt = PIX_FMT_RGB555;
176 av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
177 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);
182 if ( image->red_mask == 0xff0000 &&
183 image->green_mask == 0x00ff00 &&
184 image->blue_mask == 0x0000ff ) {
185 input_pixfmt = PIX_FMT_BGR24;
186 } else if ( image->red_mask == 0x0000ff &&
187 image->green_mask == 0x00ff00 &&
188 image->blue_mask == 0xff0000 ) {
189 input_pixfmt = PIX_FMT_RGB24;
191 av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
192 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);
198 GetColorInfo (image, &c_info);
199 if ( c_info.alpha_mask == 0xff000000 && image->green_mask == 0x0000ff00) {
200 /* byte order is relevant here, not endianness
201 * endianness is handled by avcodec, but atm no such thing
202 * as having ABGR, instead of ARGB in a word. Since we
203 * need this for Solaris/SPARC, but need to do the conversion
204 * for every frame we do it outside of this loop, cf. below
205 * this matches both ARGB32 and ABGR32 */
206 input_pixfmt = PIX_FMT_ARGB32;
208 av_log(s1, AV_LOG_ERROR,"image depth %i not supported ... aborting\n", image->bits_per_pixel);
212 input_pixfmt = PIX_FMT_RGB32;
215 av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
219 x11grab->frame_size = ap->width * ap->height * image->bits_per_pixel/8;
221 x11grab->width = ap->width;
222 x11grab->height = ap->height;
223 x11grab->time_base = ap->time_base;
224 x11grab->time_frame = av_gettime() / av_q2d(ap->time_base);
225 x11grab->x_off = x_off;
226 x11grab->y_off = y_off;
227 x11grab->image = image;
228 x11grab->use_shm = use_shm;
230 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
231 st->codec->codec_id = CODEC_ID_RAWVIDEO;
232 st->codec->width = ap->width;
233 st->codec->height = ap->height;
234 st->codec->pix_fmt = input_pixfmt;
235 st->codec->time_base = ap->time_base;
236 st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(ap->time_base) * 8;
242 * Paint a mouse pointer in an X11 image.
244 * @param image image to paint the mouse pointer to
245 * @param s context used to retrieve original grabbing rectangle
249 paint_mouse_pointer(XImage *image, struct x11_grab *s)
251 int x_off = s->x_off;
252 int y_off = s->y_off;
253 int width = s->width;
254 int height = s->height;
255 Display *dpy = s->dpy;
256 XFixesCursorImage *xcim;
259 int to_line, to_column;
260 int pixstride = image->bits_per_pixel >> 3;
261 /* Warning: in its insanity, xlib provides unsigned image data through a
262 * char* pointer, so we have to make it uint8_t to make things not break.
263 * Anyone who performs further investigation of the xlib API likely risks
264 * permanent brain damage. */
265 uint8_t *pix = image->data;
267 /* Code doesn't currently support 16-bit or PAL8 */
268 if (image->bits_per_pixel != 24 && image->bits_per_pixel != 32)
271 xcim = XFixesGetCursorImage(dpy);
273 x = xcim->x - xcim->xhot;
274 y = xcim->y - xcim->yhot;
276 to_line = FFMIN((y + xcim->height), (height + y_off));
277 to_column = FFMIN((x + xcim->width), (width + x_off));
279 for (line = FFMAX(y, y_off); line < to_line; line++) {
280 for (column = FFMAX(x, x_off); column < to_column; column++) {
281 int xcim_addr = (line - y) * xcim->width + column - x;
282 int image_addr = ((line - y_off) * width + column - x_off) * pixstride;
283 int r = (uint8_t)(xcim->pixels[xcim_addr] >> 0);
284 int g = (uint8_t)(xcim->pixels[xcim_addr] >> 8);
285 int b = (uint8_t)(xcim->pixels[xcim_addr] >> 16);
286 int a = (uint8_t)(xcim->pixels[xcim_addr] >> 24);
289 pix[image_addr+0] = r;
290 pix[image_addr+1] = g;
291 pix[image_addr+2] = b;
293 /* pixel values from XFixesGetCursorImage come premultiplied by alpha */
294 pix[image_addr+0] = r + (pix[image_addr+0]*(255-a) + 255/2) / 255;
295 pix[image_addr+1] = g + (pix[image_addr+1]*(255-a) + 255/2) / 255;
296 pix[image_addr+2] = b + (pix[image_addr+2]*(255-a) + 255/2) / 255;
307 * Read new data in the image structure.
309 * @param dpy X11 display to grab from
311 * @param image Image where the grab will be put
312 * @param x Top-Left grabbing rectangle horizontal coordinate
313 * @param y Top-Left grabbing rectangle vertical coordinate
314 * @return 0 if error, !0 if successful
317 xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
328 GetReq(GetImage, req);
330 /* First set up the standard stuff in the request */
334 req->width = image->width;
335 req->height = image->height;
336 req->planeMask = (unsigned int)AllPlanes;
337 req->format = ZPixmap;
339 if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
345 nbytes = (long)rep.length << 2;
346 _XReadPad(dpy, image->data, nbytes);
354 * Grab a frame from x11 (public device demuxer API).
356 * @param s1 Context from avformat core
357 * @param pkt Packet holding the brabbed frame
358 * @return frame size in bytes
361 x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
363 struct x11_grab *s = s1->priv_data;
364 Display *dpy = s->dpy;
365 XImage *image = s->image;
366 int x_off = s->x_off;
367 int y_off = s->y_off;
369 int64_t curtime, delay;
372 /* Calculate the time of the next frame */
373 s->time_frame += INT64_C(1000000);
375 /* wait based on the frame rate */
377 curtime = av_gettime();
378 delay = s->time_frame * av_q2d(s->time_base) - curtime;
380 if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
381 s->time_frame += INT64_C(1000000);
385 ts.tv_sec = delay / 1000000;
386 ts.tv_nsec = (delay % 1000000) * 1000;
387 nanosleep(&ts, NULL);
391 pkt->data = image->data;
392 pkt->size = s->frame_size;
396 if (!XShmGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off, AllPlanes)) {
397 av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n");
400 if (!xget_zpixmap(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off)) {
401 av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
406 paint_mouse_pointer(image, s);
409 return s->frame_size;
413 * Close x11 frame grabber (public device demuxer API).
415 * @param s1 Context from avformat core
416 * @return 0 success, !0 failure
419 x11grab_read_close(AVFormatContext *s1)
421 struct x11_grab *x11grab = s1->priv_data;
423 /* Detach cleanly from shared mem */
424 if (x11grab->use_shm) {
425 XShmDetach(x11grab->dpy, &x11grab->shminfo);
426 shmdt(x11grab->shminfo.shmaddr);
427 shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
430 /* Destroy X11 image */
431 if (x11grab->image) {
432 XDestroyImage(x11grab->image);
433 x11grab->image = NULL;
436 /* Free X11 display */
437 XCloseDisplay(x11grab->dpy);
441 /** x11 grabber device demuxer declaration */
442 AVInputFormat ff_x11_grab_device_demuxer =
445 NULL_IF_CONFIG_SMALL("X11grab"),
446 sizeof(struct x11_grab),
451 .flags = AVFMT_NOFILE,