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libavdevice/x11grab.c

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00001 /*
00002  * X11 video grab interface
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg integration:
00007  * Copyright (C) 2006 Clemens Fruhwirth <clemens@endorphin.org>
00008  *                    Edouard Gomez <ed.gomez@free.fr>
00009  *
00010  * This file contains code from grab.c:
00011  * Copyright (c) 2000-2001 Fabrice Bellard
00012  *
00013  * This file contains code from the xvidcap project:
00014  * Copyright (C) 1997-1998 Rasca, Berlin
00015  *               2003-2004 Karl H. Beckers, Frankfurt
00016  *
00017  * FFmpeg is free software; you can redistribute it and/or modify
00018  * it under the terms of the GNU General Public License as published by
00019  * the Free Software Foundation; either version 2 of the License, or
00020  * (at your option) any later version.
00021  *
00022  * FFmpeg is distributed in the hope that it will be useful,
00023  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00024  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00025  * GNU General Public License for more details.
00026  *
00027  * You should have received a copy of the GNU General Public License
00028  * along with FFmpeg; if not, write to the Free Software
00029  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00030  */
00031 
00038 #define _XOPEN_SOURCE 600
00039 
00040 #include "config.h"
00041 #include "libavformat/avformat.h"
00042 #include <time.h>
00043 #include <X11/X.h>
00044 #include <X11/Xlib.h>
00045 #include <X11/Xlibint.h>
00046 #include <X11/Xproto.h>
00047 #include <X11/Xutil.h>
00048 #include <sys/shm.h>
00049 #include <X11/extensions/XShm.h>
00050 #include <X11/extensions/Xfixes.h>
00051 
00055 struct x11_grab
00056 {
00057     int frame_size;          
00058     AVRational time_base;    
00059     int64_t time_frame;      
00061     int height;              
00062     int width;               
00063     int x_off;               
00064     int y_off;               
00066     Display *dpy;            
00067     XImage *image;           
00068     int use_shm;             
00069     XShmSegmentInfo shminfo; 
00070     int nomouse;
00071 };
00072 
00084 static int
00085 x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
00086 {
00087     struct x11_grab *x11grab = s1->priv_data;
00088     Display *dpy;
00089     AVStream *st = NULL;
00090     enum PixelFormat input_pixfmt;
00091     XImage *image;
00092     int x_off = 0;
00093     int y_off = 0;
00094     int use_shm;
00095     char *param, *offset;
00096 
00097     param = av_strdup(s1->filename);
00098     offset = strchr(param, '+');
00099     if (offset) {
00100         sscanf(offset, "%d,%d", &x_off, &y_off);
00101         x11grab->nomouse= strstr(offset, "nomouse");
00102         *offset= 0;
00103     }
00104 
00105     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);
00106 
00107     dpy = XOpenDisplay(param);
00108     if(!dpy) {
00109         av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
00110         return AVERROR(EIO);
00111     }
00112 
00113     if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
00114         av_log(s1, AV_LOG_ERROR, "AVParameters don't have video size and/or rate. Use -s and -r.\n");
00115         return AVERROR(EIO);
00116     }
00117 
00118     st = av_new_stream(s1, 0);
00119     if (!st) {
00120         return AVERROR(ENOMEM);
00121     }
00122     av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
00123 
00124     use_shm = XShmQueryExtension(dpy);
00125     av_log(s1, AV_LOG_INFO, "shared memory extension %s found\n", use_shm ? "" : "not");
00126 
00127     if(use_shm) {
00128         int scr = XDefaultScreen(dpy);
00129         image = XShmCreateImage(dpy,
00130                                 DefaultVisual(dpy, scr),
00131                                 DefaultDepth(dpy, scr),
00132                                 ZPixmap,
00133                                 NULL,
00134                                 &x11grab->shminfo,
00135                                 ap->width, ap->height);
00136         x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
00137                                         image->bytes_per_line * image->height,
00138                                         IPC_CREAT|0777);
00139         if (x11grab->shminfo.shmid == -1) {
00140             av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
00141             return AVERROR(ENOMEM);
00142         }
00143         x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
00144         x11grab->shminfo.readOnly = False;
00145 
00146         if (!XShmAttach(dpy, &x11grab->shminfo)) {
00147             av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
00148             /* needs some better error subroutine :) */
00149             return AVERROR(EIO);
00150         }
00151     } else {
00152         image = XGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)),
00153                           x_off,y_off,
00154                           ap->width,ap->height,
00155                           AllPlanes, ZPixmap);
00156     }
00157 
00158     switch (image->bits_per_pixel) {
00159     case 8:
00160         av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
00161         input_pixfmt = PIX_FMT_PAL8;
00162         break;
00163     case 16:
00164         if (       image->red_mask   == 0xf800 &&
00165                    image->green_mask == 0x07e0 &&
00166                    image->blue_mask  == 0x001f ) {
00167             av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
00168             input_pixfmt = PIX_FMT_RGB565;
00169         } else if (image->red_mask   == 0x7c00 &&
00170                    image->green_mask == 0x03e0 &&
00171                    image->blue_mask  == 0x001f ) {
00172             av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
00173             input_pixfmt = PIX_FMT_RGB555;
00174         } else {
00175             av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
00176             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);
00177             return AVERROR(EIO);
00178         }
00179         break;
00180     case 24:
00181         if (        image->red_mask   == 0xff0000 &&
00182                     image->green_mask == 0x00ff00 &&
00183                     image->blue_mask  == 0x0000ff ) {
00184             input_pixfmt = PIX_FMT_BGR24;
00185         } else if ( image->red_mask   == 0x0000ff &&
00186                     image->green_mask == 0x00ff00 &&
00187                     image->blue_mask  == 0xff0000 ) {
00188             input_pixfmt = PIX_FMT_RGB24;
00189         } else {
00190             av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
00191             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);
00192             return AVERROR(EIO);
00193         }
00194         break;
00195     case 32:
00196 #if 0
00197         GetColorInfo (image, &c_info);
00198         if ( c_info.alpha_mask == 0xff000000 && image->green_mask == 0x0000ff00) {
00199             /* byte order is relevant here, not endianness
00200              * endianness is handled by avcodec, but atm no such thing
00201              * as having ABGR, instead of ARGB in a word. Since we
00202              * need this for Solaris/SPARC, but need to do the conversion
00203              * for every frame we do it outside of this loop, cf. below
00204              * this matches both ARGB32 and ABGR32 */
00205             input_pixfmt = PIX_FMT_ARGB32;
00206         }  else {
00207             av_log(s1, AV_LOG_ERROR,"image depth %i not supported ... aborting\n", image->bits_per_pixel);
00208             return AVERROR(EIO);
00209         }
00210 #endif
00211         input_pixfmt = PIX_FMT_RGB32;
00212         break;
00213     default:
00214         av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
00215         return -1;
00216     }
00217 
00218     x11grab->frame_size = ap->width * ap->height * image->bits_per_pixel/8;
00219     x11grab->dpy = dpy;
00220     x11grab->width = ap->width;
00221     x11grab->height = ap->height;
00222     x11grab->time_base  = ap->time_base;
00223     x11grab->time_frame = av_gettime() / av_q2d(ap->time_base);
00224     x11grab->x_off = x_off;
00225     x11grab->y_off = y_off;
00226     x11grab->image = image;
00227     x11grab->use_shm = use_shm;
00228 
00229     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00230     st->codec->codec_id = CODEC_ID_RAWVIDEO;
00231     st->codec->width = ap->width;
00232     st->codec->height = ap->height;
00233     st->codec->pix_fmt = input_pixfmt;
00234     st->codec->time_base = ap->time_base;
00235     st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(ap->time_base) * 8;
00236 
00237     return 0;
00238 }
00239 
00249 static void
00250 paint_mouse_pointer(XImage *image, struct x11_grab *s)
00251 {
00252     int x_off = s->x_off;
00253     int y_off = s->y_off;
00254     int width = s->width;
00255     int height = s->height;
00256     Display *dpy = s->dpy;
00257     XFixesCursorImage *xcim;
00258     int x, y;
00259     int line, column;
00260     int to_line, to_column;
00261     int image_addr, xcim_addr;
00262 
00263     xcim = XFixesGetCursorImage(dpy);;
00264 
00265     x = xcim->x - xcim->xhot;
00266     y = xcim->y - xcim->yhot;
00267 
00268     to_line = FFMIN((y + xcim->height), (height + y_off));
00269     to_column = FFMIN((x + xcim->width), (width + x_off));
00270 
00271     for (line = FFMAX(y, y_off); line < to_line; line++) {
00272         for (column = FFMAX(x, x_off); column < to_column; column++) {
00273             xcim_addr = (line - y) * xcim->width + column - x;
00274 
00275             if ((unsigned char)(xcim->pixels[xcim_addr] >> 24) != 0) { // skip fully transparent pixel
00276                 image_addr = ((line - y_off) * width + column - x_off) * 4;
00277 
00278                 image->data[image_addr] = (unsigned char)(xcim->pixels[xcim_addr] >> 0);
00279                 image->data[image_addr+1] = (unsigned char)(xcim->pixels[xcim_addr] >> 8);
00280                 image->data[image_addr+2] = (unsigned char)(xcim->pixels[xcim_addr] >> 16);
00281             }
00282         }
00283     }
00284 
00285     XFree(xcim);
00286     xcim = NULL;
00287 }
00288 
00289 
00300 static int
00301 xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
00302 {
00303     xGetImageReply rep;
00304     xGetImageReq *req;
00305     long nbytes;
00306 
00307     if (!image) {
00308         return 0;
00309     }
00310 
00311     LockDisplay(dpy);
00312     GetReq(GetImage, req);
00313 
00314     /* First set up the standard stuff in the request */
00315     req->drawable = d;
00316     req->x = x;
00317     req->y = y;
00318     req->width = image->width;
00319     req->height = image->height;
00320     req->planeMask = (unsigned int)AllPlanes;
00321     req->format = ZPixmap;
00322 
00323     if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
00324         UnlockDisplay(dpy);
00325         SyncHandle();
00326         return 0;
00327     }
00328 
00329     nbytes = (long)rep.length << 2;
00330     _XReadPad(dpy, image->data, nbytes);
00331 
00332     UnlockDisplay(dpy);
00333     SyncHandle();
00334     return 1;
00335 }
00336 
00344 static int
00345 x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
00346 {
00347     struct x11_grab *s = s1->priv_data;
00348     Display *dpy = s->dpy;
00349     XImage *image = s->image;
00350     int x_off = s->x_off;
00351     int y_off = s->y_off;
00352 
00353     int64_t curtime, delay;
00354     struct timespec ts;
00355 
00356     /* Calculate the time of the next frame */
00357     s->time_frame += INT64_C(1000000);
00358 
00359     /* wait based on the frame rate */
00360     for(;;) {
00361         curtime = av_gettime();
00362         delay = s->time_frame * av_q2d(s->time_base) - curtime;
00363         if (delay <= 0) {
00364             if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
00365                 s->time_frame += INT64_C(1000000);
00366             }
00367             break;
00368         }
00369         ts.tv_sec = delay / 1000000;
00370         ts.tv_nsec = (delay % 1000000) * 1000;
00371         nanosleep(&ts, NULL);
00372     }
00373 
00374     if (av_new_packet(pkt, s->frame_size) < 0) {
00375         return AVERROR(EIO);
00376     }
00377 
00378     pkt->pts = curtime;
00379 
00380     if(s->use_shm) {
00381         if (!XShmGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off, AllPlanes)) {
00382             av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n");
00383         }
00384     } else {
00385         if (!xget_zpixmap(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off)) {
00386             av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
00387         }
00388     }
00389 
00390     if(!s->nomouse){
00391         paint_mouse_pointer(image, s);
00392     }
00393 
00394 
00395     /* XXX: avoid memcpy */
00396     memcpy(pkt->data, image->data, s->frame_size);
00397     return s->frame_size;
00398 }
00399 
00406 static int
00407 x11grab_read_close(AVFormatContext *s1)
00408 {
00409     struct x11_grab *x11grab = s1->priv_data;
00410 
00411     /* Detach cleanly from shared mem */
00412     if (x11grab->use_shm) {
00413         XShmDetach(x11grab->dpy, &x11grab->shminfo);
00414         shmdt(x11grab->shminfo.shmaddr);
00415         shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
00416     }
00417 
00418     /* Destroy X11 image */
00419     if (x11grab->image) {
00420         XDestroyImage(x11grab->image);
00421         x11grab->image = NULL;
00422     }
00423 
00424     /* Free X11 display */
00425     XCloseDisplay(x11grab->dpy);
00426     return 0;
00427 }
00428 
00430 AVInputFormat x11_grab_device_demuxer =
00431 {
00432     "x11grab",
00433     NULL_IF_CONFIG_SMALL("X11grab"),
00434     sizeof(struct x11_grab),
00435     NULL,
00436     x11grab_read_header,
00437     x11grab_read_packet,
00438     x11grab_read_close,
00439     .flags = AVFMT_NOFILE,
00440 };

Generated on Fri Sep 16 2011 17:17:47 for FFmpeg by  doxygen 1.7.1