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>.
39 #include "libavformat/avformat.h"
43 #include <X11/Xlibint.h>
44 #include <X11/Xproto.h>
45 #include <X11/Xutil.h>
47 #include <X11/extensions/XShm.h>
48 #include <X11/extensions/Xfixes.h>
51 * X11 Device Demuxer context
55 int frame_size; /**< Size in bytes of a grabbed frame */
56 AVRational time_base; /**< Time base */
57 int64_t time_frame; /**< Current time */
59 int height; /**< Height of the grab frame */
60 int width; /**< Width of the grab frame */
61 int x_off; /**< Horizontal top-left corner coordinate */
62 int y_off; /**< Vertical top-left corner coordinate */
64 Display *dpy; /**< X11 display from which x11grab grabs frames */
65 XImage *image; /**< X11 image holding the grab */
66 int use_shm; /**< !0 when using XShm extension */
67 XShmSegmentInfo shminfo; /**< When using XShm, keeps track of XShm infos */
72 * Initialize the x11 grab device demuxer (public device demuxer API).
74 * @param s1 Context from avformat core
75 * @param ap Parameters from avformat core
77 * <li>AVERROR(ENOMEM) no memory left</li>
78 * <li>AVERROR(EIO) other failure case</li>
83 x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
85 struct x11_grab *x11grab = s1->priv_data;
88 enum PixelFormat input_pixfmt;
93 char *dpyname, *offset;
95 dpyname = av_strdup(s1->filename);
96 offset = strchr(dpyname, '+');
98 sscanf(offset, "%d,%d", &x_off, &y_off);
99 x11grab->nomouse= strstr(offset, "nomouse");
103 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);
105 dpy = XOpenDisplay(dpyname);
108 av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
112 if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
113 av_log(s1, AV_LOG_ERROR, "AVParameters don't have video size and/or rate. Use -s and -r.\n");
117 st = av_new_stream(s1, 0);
119 return AVERROR(ENOMEM);
121 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
123 use_shm = XShmQueryExtension(dpy);
124 av_log(s1, AV_LOG_INFO, "shared memory extension%s found\n", use_shm ? "" : " not");
127 int scr = XDefaultScreen(dpy);
128 image = XShmCreateImage(dpy,
129 DefaultVisual(dpy, scr),
130 DefaultDepth(dpy, scr),
134 ap->width, ap->height);
135 x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
136 image->bytes_per_line * image->height,
138 if (x11grab->shminfo.shmid == -1) {
139 av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
140 return AVERROR(ENOMEM);
142 x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
143 x11grab->shminfo.readOnly = False;
145 if (!XShmAttach(dpy, &x11grab->shminfo)) {
146 av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
147 /* needs some better error subroutine :) */
151 image = XGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)),
153 ap->width,ap->height,
157 switch (image->bits_per_pixel) {
159 av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
160 input_pixfmt = PIX_FMT_PAL8;
163 if ( image->red_mask == 0xf800 &&
164 image->green_mask == 0x07e0 &&
165 image->blue_mask == 0x001f ) {
166 av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
167 input_pixfmt = PIX_FMT_RGB565;
168 } else if (image->red_mask == 0x7c00 &&
169 image->green_mask == 0x03e0 &&
170 image->blue_mask == 0x001f ) {
171 av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
172 input_pixfmt = PIX_FMT_RGB555;
174 av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
175 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);
180 if ( image->red_mask == 0xff0000 &&
181 image->green_mask == 0x00ff00 &&
182 image->blue_mask == 0x0000ff ) {
183 input_pixfmt = PIX_FMT_BGR24;
184 } else if ( image->red_mask == 0x0000ff &&
185 image->green_mask == 0x00ff00 &&
186 image->blue_mask == 0xff0000 ) {
187 input_pixfmt = PIX_FMT_RGB24;
189 av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
190 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);
196 GetColorInfo (image, &c_info);
197 if ( c_info.alpha_mask == 0xff000000 && image->green_mask == 0x0000ff00) {
198 /* byte order is relevant here, not endianness
199 * endianness is handled by avcodec, but atm no such thing
200 * as having ABGR, instead of ARGB in a word. Since we
201 * need this for Solaris/SPARC, but need to do the conversion
202 * for every frame we do it outside of this loop, cf. below
203 * this matches both ARGB32 and ABGR32 */
204 input_pixfmt = PIX_FMT_ARGB32;
206 av_log(s1, AV_LOG_ERROR,"image depth %i not supported ... aborting\n", image->bits_per_pixel);
210 input_pixfmt = PIX_FMT_RGB32;
213 av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
217 x11grab->frame_size = ap->width * ap->height * image->bits_per_pixel/8;
219 x11grab->width = ap->width;
220 x11grab->height = ap->height;
221 x11grab->time_base = ap->time_base;
222 x11grab->time_frame = av_gettime() / av_q2d(ap->time_base);
223 x11grab->x_off = x_off;
224 x11grab->y_off = y_off;
225 x11grab->image = image;
226 x11grab->use_shm = use_shm;
228 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
229 st->codec->codec_id = CODEC_ID_RAWVIDEO;
230 st->codec->width = ap->width;
231 st->codec->height = ap->height;
232 st->codec->pix_fmt = input_pixfmt;
233 st->codec->time_base = ap->time_base;
234 st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(ap->time_base) * 8;
240 * Paint a mouse pointer in an X11 image.
242 * @param image image to paint the mouse pointer to
243 * @param s context used to retrieve original grabbing rectangle
247 paint_mouse_pointer(XImage *image, struct x11_grab *s)
249 int x_off = s->x_off;
250 int y_off = s->y_off;
251 int width = s->width;
252 int height = s->height;
253 Display *dpy = s->dpy;
254 XFixesCursorImage *xcim;
257 int to_line, to_column;
258 int pixstride = image->bits_per_pixel >> 3;
259 /* Warning: in its insanity, xlib provides unsigned image data through a
260 * char* pointer, so we have to make it uint8_t to make things not break.
261 * Anyone who performs further investigation of the xlib API likely risks
262 * permanent brain damage. */
263 uint8_t *pix = image->data;
265 /* Code doesn't currently support 16-bit or PAL8 */
266 if (image->bits_per_pixel != 24 && image->bits_per_pixel != 32)
269 xcim = XFixesGetCursorImage(dpy);
271 x = xcim->x - xcim->xhot;
272 y = xcim->y - xcim->yhot;
274 to_line = FFMIN((y + xcim->height), (height + y_off));
275 to_column = FFMIN((x + xcim->width), (width + x_off));
277 for (line = FFMAX(y, y_off); line < to_line; line++) {
278 for (column = FFMAX(x, x_off); column < to_column; column++) {
279 int xcim_addr = (line - y) * xcim->width + column - x;
280 int image_addr = ((line - y_off) * width + column - x_off) * pixstride;
281 int r = (uint8_t)(xcim->pixels[xcim_addr] >> 0);
282 int g = (uint8_t)(xcim->pixels[xcim_addr] >> 8);
283 int b = (uint8_t)(xcim->pixels[xcim_addr] >> 16);
284 int a = (uint8_t)(xcim->pixels[xcim_addr] >> 24);
287 pix[image_addr+0] = r;
288 pix[image_addr+1] = g;
289 pix[image_addr+2] = b;
291 /* pixel values from XFixesGetCursorImage come premultiplied by alpha */
292 pix[image_addr+0] = r + (pix[image_addr+0]*(255-a) + 255/2) / 255;
293 pix[image_addr+1] = g + (pix[image_addr+1]*(255-a) + 255/2) / 255;
294 pix[image_addr+2] = b + (pix[image_addr+2]*(255-a) + 255/2) / 255;
305 * Read new data in the image structure.
307 * @param dpy X11 display to grab from
309 * @param image Image where the grab will be put
310 * @param x Top-Left grabbing rectangle horizontal coordinate
311 * @param y Top-Left grabbing rectangle vertical coordinate
312 * @return 0 if error, !0 if successful
315 xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
326 GetReq(GetImage, req);
328 /* First set up the standard stuff in the request */
332 req->width = image->width;
333 req->height = image->height;
334 req->planeMask = (unsigned int)AllPlanes;
335 req->format = ZPixmap;
337 if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
343 nbytes = (long)rep.length << 2;
344 _XReadPad(dpy, image->data, nbytes);
352 * Grab a frame from x11 (public device demuxer API).
354 * @param s1 Context from avformat core
355 * @param pkt Packet holding the brabbed frame
356 * @return frame size in bytes
359 x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
361 struct x11_grab *s = s1->priv_data;
362 Display *dpy = s->dpy;
363 XImage *image = s->image;
364 int x_off = s->x_off;
365 int y_off = s->y_off;
367 int64_t curtime, delay;
370 /* Calculate the time of the next frame */
371 s->time_frame += INT64_C(1000000);
373 /* wait based on the frame rate */
375 curtime = av_gettime();
376 delay = s->time_frame * av_q2d(s->time_base) - curtime;
378 if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
379 s->time_frame += INT64_C(1000000);
383 ts.tv_sec = delay / 1000000;
384 ts.tv_nsec = (delay % 1000000) * 1000;
385 nanosleep(&ts, NULL);
389 pkt->data = image->data;
390 pkt->size = s->frame_size;
394 if (!XShmGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off, AllPlanes)) {
395 av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n");
398 if (!xget_zpixmap(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off)) {
399 av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
404 paint_mouse_pointer(image, s);
407 return s->frame_size;
411 * Close x11 frame grabber (public device demuxer API).
413 * @param s1 Context from avformat core
414 * @return 0 success, !0 failure
417 x11grab_read_close(AVFormatContext *s1)
419 struct x11_grab *x11grab = s1->priv_data;
421 /* Detach cleanly from shared mem */
422 if (x11grab->use_shm) {
423 XShmDetach(x11grab->dpy, &x11grab->shminfo);
424 shmdt(x11grab->shminfo.shmaddr);
425 shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
428 /* Destroy X11 image */
429 if (x11grab->image) {
430 XDestroyImage(x11grab->image);
431 x11grab->image = NULL;
434 /* Free X11 display */
435 XCloseDisplay(x11grab->dpy);
439 /** x11 grabber device demuxer declaration */
440 AVInputFormat ff_x11_grab_device_demuxer =
443 NULL_IF_CONFIG_SMALL("X11grab"),
444 sizeof(struct x11_grab),
449 .flags = AVFMT_NOFILE,