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;
97 param = av_strdup(s1->filename);
98 offset = strchr(param, '+');
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, param, x_off, y_off, ap->width, ap->height);
107 dpy = XOpenDisplay(param);
109 av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
113 if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
114 av_log(s1, AV_LOG_ERROR, "AVParameters don't have video size and/or rate. Use -s and -r.\n");
118 st = av_new_stream(s1, 0);
120 return AVERROR(ENOMEM);
122 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
124 use_shm = XShmQueryExtension(dpy);
125 av_log(s1, AV_LOG_INFO, "shared memory extension %s found\n", use_shm ? "" : "not");
128 int scr = XDefaultScreen(dpy);
129 image = XShmCreateImage(dpy,
130 DefaultVisual(dpy, scr),
131 DefaultDepth(dpy, scr),
135 ap->width, ap->height);
136 x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
137 image->bytes_per_line * image->height,
139 if (x11grab->shminfo.shmid == -1) {
140 av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
141 return AVERROR(ENOMEM);
143 x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
144 x11grab->shminfo.readOnly = False;
146 if (!XShmAttach(dpy, &x11grab->shminfo)) {
147 av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
148 /* needs some better error subroutine :) */
152 image = XGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)),
154 ap->width,ap->height,
158 switch (image->bits_per_pixel) {
160 av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
161 input_pixfmt = PIX_FMT_PAL8;
164 if ( image->red_mask == 0xf800 &&
165 image->green_mask == 0x07e0 &&
166 image->blue_mask == 0x001f ) {
167 av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
168 input_pixfmt = PIX_FMT_RGB565;
169 } else if (image->red_mask == 0x7c00 &&
170 image->green_mask == 0x03e0 &&
171 image->blue_mask == 0x001f ) {
172 av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
173 input_pixfmt = PIX_FMT_RGB555;
175 av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
176 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);
181 if ( image->red_mask == 0xff0000 &&
182 image->green_mask == 0x00ff00 &&
183 image->blue_mask == 0x0000ff ) {
184 input_pixfmt = PIX_FMT_BGR24;
185 } else if ( image->red_mask == 0x0000ff &&
186 image->green_mask == 0x00ff00 &&
187 image->blue_mask == 0xff0000 ) {
188 input_pixfmt = PIX_FMT_RGB24;
190 av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
191 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);
197 GetColorInfo (image, &c_info);
198 if ( c_info.alpha_mask == 0xff000000 && image->green_mask == 0x0000ff00) {
199 /* byte order is relevant here, not endianness
200 * endianness is handled by avcodec, but atm no such thing
201 * as having ABGR, instead of ARGB in a word. Since we
202 * need this for Solaris/SPARC, but need to do the conversion
203 * for every frame we do it outside of this loop, cf. below
204 * this matches both ARGB32 and ABGR32 */
205 input_pixfmt = PIX_FMT_ARGB32;
207 av_log(s1, AV_LOG_ERROR,"image depth %i not supported ... aborting\n", image->bits_per_pixel);
211 input_pixfmt = PIX_FMT_RGB32;
214 av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
218 x11grab->frame_size = ap->width * ap->height * image->bits_per_pixel/8;
220 x11grab->width = ap->width;
221 x11grab->height = ap->height;
222 x11grab->time_base = ap->time_base;
223 x11grab->time_frame = av_gettime() / av_q2d(ap->time_base);
224 x11grab->x_off = x_off;
225 x11grab->y_off = y_off;
226 x11grab->image = image;
227 x11grab->use_shm = use_shm;
229 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
230 st->codec->codec_id = CODEC_ID_RAWVIDEO;
231 st->codec->width = ap->width;
232 st->codec->height = ap->height;
233 st->codec->pix_fmt = input_pixfmt;
234 st->codec->time_base = ap->time_base;
235 st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(ap->time_base) * 8;
241 * Paint a mouse pointer in an X11 image.
243 * @param image image to paint the mouse pointer to
244 * @param s context used to retrieve original grabbing rectangle
248 paint_mouse_pointer(XImage *image, struct x11_grab *s)
250 int x_off = s->x_off;
251 int y_off = s->y_off;
252 int width = s->width;
253 int height = s->height;
254 Display *dpy = s->dpy;
255 XFixesCursorImage *xcim;
258 int to_line, to_column;
259 int pixstride = image->bits_per_pixel >> 3;
260 /* Warning: in its insanity, xlib provides unsigned image data through a
261 * char* pointer, so we have to make it uint8_t to make things not break.
262 * Anyone who performs further investigation of the xlib API likely risks
263 * permanent brain damage. */
264 uint8_t *pix = image->data;
266 /* Code doesn't currently support 16-bit or PAL8 */
267 if (image->bits_per_pixel != 24 && image->bits_per_pixel != 32)
270 xcim = XFixesGetCursorImage(dpy);
272 x = xcim->x - xcim->xhot;
273 y = xcim->y - xcim->yhot;
275 to_line = FFMIN((y + xcim->height), (height + y_off));
276 to_column = FFMIN((x + xcim->width), (width + x_off));
278 for (line = FFMAX(y, y_off); line < to_line; line++) {
279 for (column = FFMAX(x, x_off); column < to_column; column++) {
280 int xcim_addr = (line - y) * xcim->width + column - x;
281 int image_addr = ((line - y_off) * width + column - x_off) * pixstride;
282 int r = (uint8_t)(xcim->pixels[xcim_addr] >> 0);
283 int g = (uint8_t)(xcim->pixels[xcim_addr] >> 8);
284 int b = (uint8_t)(xcim->pixels[xcim_addr] >> 16);
285 int a = (uint8_t)(xcim->pixels[xcim_addr] >> 24);
288 pix[image_addr+0] = r;
289 pix[image_addr+1] = g;
290 pix[image_addr+2] = b;
292 /* pixel values from XFixesGetCursorImage come premultiplied by alpha */
293 pix[image_addr+0] = r + (pix[image_addr+0]*(255-a) + 255/2) / 255;
294 pix[image_addr+1] = g + (pix[image_addr+1]*(255-a) + 255/2) / 255;
295 pix[image_addr+2] = b + (pix[image_addr+2]*(255-a) + 255/2) / 255;
306 * Read new data in the image structure.
308 * @param dpy X11 display to grab from
310 * @param image Image where the grab will be put
311 * @param x Top-Left grabbing rectangle horizontal coordinate
312 * @param y Top-Left grabbing rectangle vertical coordinate
313 * @return 0 if error, !0 if successful
316 xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
327 GetReq(GetImage, req);
329 /* First set up the standard stuff in the request */
333 req->width = image->width;
334 req->height = image->height;
335 req->planeMask = (unsigned int)AllPlanes;
336 req->format = ZPixmap;
338 if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
344 nbytes = (long)rep.length << 2;
345 _XReadPad(dpy, image->data, nbytes);
353 * Grab a frame from x11 (public device demuxer API).
355 * @param s1 Context from avformat core
356 * @param pkt Packet holding the brabbed frame
357 * @return frame size in bytes
360 x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
362 struct x11_grab *s = s1->priv_data;
363 Display *dpy = s->dpy;
364 XImage *image = s->image;
365 int x_off = s->x_off;
366 int y_off = s->y_off;
368 int64_t curtime, delay;
371 /* Calculate the time of the next frame */
372 s->time_frame += INT64_C(1000000);
374 /* wait based on the frame rate */
376 curtime = av_gettime();
377 delay = s->time_frame * av_q2d(s->time_base) - curtime;
379 if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
380 s->time_frame += INT64_C(1000000);
384 ts.tv_sec = delay / 1000000;
385 ts.tv_nsec = (delay % 1000000) * 1000;
386 nanosleep(&ts, NULL);
389 if (av_new_packet(pkt, s->frame_size) < 0) {
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);
410 /* XXX: avoid memcpy */
411 memcpy(pkt->data, image->data, s->frame_size);
412 return s->frame_size;
416 * Close x11 frame grabber (public device demuxer API).
418 * @param s1 Context from avformat core
419 * @return 0 success, !0 failure
422 x11grab_read_close(AVFormatContext *s1)
424 struct x11_grab *x11grab = s1->priv_data;
426 /* Detach cleanly from shared mem */
427 if (x11grab->use_shm) {
428 XShmDetach(x11grab->dpy, &x11grab->shminfo);
429 shmdt(x11grab->shminfo.shmaddr);
430 shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
433 /* Destroy X11 image */
434 if (x11grab->image) {
435 XDestroyImage(x11grab->image);
436 x11grab->image = NULL;
439 /* Free X11 display */
440 XCloseDisplay(x11grab->dpy);
444 /** x11 grabber device demuxer declaration */
445 AVInputFormat ff_x11_grab_device_demuxer =
448 NULL_IF_CONFIG_SMALL("X11grab"),
449 sizeof(struct x11_grab),
454 .flags = AVFMT_NOFILE,