FFmpeg: libavdevice/x11grab.c Source File

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 #include "config.h"
00039 #include "libavformat/avformat.h"
00040 #include <unistd.h>
00041 #include <fcntl.h>
00042 #include <sys/ioctl.h>
00043 #include <sys/time.h>
00044 #define _LINUX_TIME_H 1
00045 #include <time.h>
00046 #include <X11/X.h>
00047 #include <X11/Xlib.h>
00048 #include <X11/Xlibint.h>
00049 #include <X11/Xproto.h>
00050 #include <X11/Xutil.h>
00051 #include <sys/ipc.h>
00052 #include <sys/shm.h>
00053 #include <X11/extensions/XShm.h>
00054 
00058 struct x11_grab
00059 {
00060     int frame_size;          
00061     AVRational time_base;    
00062     int64_t time_frame;      
00064     int height;              
00065     int width;               
00066     int x_off;               
00067     int y_off;               
00069     Display *dpy;            
00070     XImage *image;           
00071     int use_shm;             
00072     XShmSegmentInfo shminfo; 
00073     int mouse_warning_shown;
00074 };
00075 
00087 static int
00088 x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
00089 {
00090     struct x11_grab *x11grab = s1->priv_data;
00091     Display *dpy;
00092     AVStream *st = NULL;
00093     int input_pixfmt;
00094     XImage *image;
00095     int x_off = 0;
00096     int y_off = 0;
00097     int use_shm;
00098     char *param, *offset;
00099 
00100     param = av_strdup(s1->filename);
00101     offset = strchr(param, '+');
00102     if (offset) {
00103         sscanf(offset, "%d,%d", &x_off, &y_off);
00104         *offset= 0;
00105     }
00106 
00107     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);
00108 
00109     dpy = XOpenDisplay(param);
00110     if(!dpy) {
00111         av_log(s1, AV_LOG_ERROR, "Could not open X display.\n");
00112         return AVERROR(EIO);
00113     }
00114 
00115     if (!ap || ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
00116         av_log(s1, AV_LOG_ERROR, "AVParameters don't have video size and/or rate. Use -s and -r.\n");
00117         return AVERROR(EIO);
00118     }
00119 
00120     st = av_new_stream(s1, 0);
00121     if (!st) {
00122         return AVERROR(ENOMEM);
00123     }
00124     av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
00125 
00126     use_shm = XShmQueryExtension(dpy);
00127     av_log(s1, AV_LOG_INFO, "shared memory extension %s found\n", use_shm ? "" : "not");
00128 
00129     if(use_shm) {
00130         int scr = XDefaultScreen(dpy);
00131         image = XShmCreateImage(dpy,
00132                                 DefaultVisual(dpy, scr),
00133                                 DefaultDepth(dpy, scr),
00134                                 ZPixmap,
00135                                 NULL,
00136                                 &x11grab->shminfo,
00137                                 ap->width, ap->height);
00138         x11grab->shminfo.shmid = shmget(IPC_PRIVATE,
00139                                         image->bytes_per_line * image->height,
00140                                         IPC_CREAT|0777);
00141         if (x11grab->shminfo.shmid == -1) {
00142             av_log(s1, AV_LOG_ERROR, "Fatal: Can't get shared memory!\n");
00143             return AVERROR(ENOMEM);
00144         }
00145         x11grab->shminfo.shmaddr = image->data = shmat(x11grab->shminfo.shmid, 0, 0);
00146         x11grab->shminfo.readOnly = False;
00147 
00148         if (!XShmAttach(dpy, &x11grab->shminfo)) {
00149             av_log(s1, AV_LOG_ERROR, "Fatal: Failed to attach shared memory!\n");
00150             /* needs some better error subroutine :) */
00151             return AVERROR(EIO);
00152         }
00153     } else {
00154         image = XGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)),
00155                           x_off,y_off,
00156                           ap->width,ap->height,
00157                           AllPlanes, ZPixmap);
00158     }
00159 
00160     switch (image->bits_per_pixel) {
00161     case 8:
00162         av_log (s1, AV_LOG_DEBUG, "8 bit palette\n");
00163         input_pixfmt = PIX_FMT_PAL8;
00164         break;
00165     case 16:
00166         if (       image->red_mask   == 0xf800 &&
00167                    image->green_mask == 0x07e0 &&
00168                    image->blue_mask  == 0x001f ) {
00169             av_log (s1, AV_LOG_DEBUG, "16 bit RGB565\n");
00170             input_pixfmt = PIX_FMT_RGB565;
00171         } else if (image->red_mask   == 0x7c00 &&
00172                    image->green_mask == 0x03e0 &&
00173                    image->blue_mask  == 0x001f ) {
00174             av_log(s1, AV_LOG_DEBUG, "16 bit RGB555\n");
00175             input_pixfmt = PIX_FMT_RGB555;
00176         } else {
00177             av_log(s1, AV_LOG_ERROR, "RGB ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
00178             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);
00179             return AVERROR(EIO);
00180         }
00181         break;
00182     case 24:
00183         if (        image->red_mask   == 0xff0000 &&
00184                     image->green_mask == 0x00ff00 &&
00185                     image->blue_mask  == 0x0000ff ) {
00186             input_pixfmt = PIX_FMT_BGR24;
00187         } else if ( image->red_mask   == 0x0000ff &&
00188                     image->green_mask == 0x00ff00 &&
00189                     image->blue_mask  == 0xff0000 ) {
00190             input_pixfmt = PIX_FMT_RGB24;
00191         } else {
00192             av_log(s1, AV_LOG_ERROR,"rgb ordering at image depth %i not supported ... aborting\n", image->bits_per_pixel);
00193             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);
00194             return AVERROR(EIO);
00195         }
00196         break;
00197     case 32:
00198 #if 0
00199         GetColorInfo (image, &c_info);
00200         if ( c_info.alpha_mask == 0xff000000 && image->green_mask == 0x0000ff00) {
00201             /* byte order is relevant here, not endianness
00202              * endianness is handled by avcodec, but atm no such thing
00203              * as having ABGR, instead of ARGB in a word. Since we
00204              * need this for Solaris/SPARC, but need to do the conversion
00205              * for every frame we do it outside of this loop, cf. below
00206              * this matches both ARGB32 and ABGR32 */
00207             input_pixfmt = PIX_FMT_ARGB32;
00208         }  else {
00209             av_log(s1, AV_LOG_ERROR,"image depth %i not supported ... aborting\n", image->bits_per_pixel);
00210             return AVERROR(EIO);
00211         }
00212 #endif
00213         input_pixfmt = PIX_FMT_RGB32;
00214         break;
00215     default:
00216         av_log(s1, AV_LOG_ERROR, "image depth %i not supported ... aborting\n", image->bits_per_pixel);
00217         return -1;
00218     }
00219 
00220     x11grab->frame_size = ap->width * ap->height * image->bits_per_pixel/8;
00221     x11grab->dpy = dpy;
00222     x11grab->width = ap->width;
00223     x11grab->height = ap->height;
00224     x11grab->time_base  = ap->time_base;
00225     x11grab->time_frame = av_gettime() / av_q2d(ap->time_base);
00226     x11grab->x_off = x_off;
00227     x11grab->y_off = y_off;
00228     x11grab->image = image;
00229     x11grab->use_shm = use_shm;
00230     x11grab->mouse_warning_shown = 0;
00231 
00232     st->codec->codec_type = CODEC_TYPE_VIDEO;
00233     st->codec->codec_id = CODEC_ID_RAWVIDEO;
00234     st->codec->width = ap->width;
00235     st->codec->height = ap->height;
00236     st->codec->pix_fmt = input_pixfmt;
00237     st->codec->time_base = ap->time_base;
00238     st->codec->bit_rate = x11grab->frame_size * 1/av_q2d(ap->time_base) * 8;
00239 
00240     return 0;
00241 }
00242 
00251 static void
00252 get_pointer_coordinates(int *x, int *y, Display *dpy, AVFormatContext *s1)
00253 {
00254     Window mrootwindow, childwindow;
00255     int dummy;
00256 
00257     mrootwindow = DefaultRootWindow(dpy);
00258 
00259     if (XQueryPointer(dpy, mrootwindow, &mrootwindow, &childwindow,
00260                       x, y, &dummy, &dummy, (unsigned int*)&dummy)) {
00261     } else {
00262         struct x11_grab *s = s1->priv_data;
00263         if (!s->mouse_warning_shown) {
00264             av_log(s1, AV_LOG_INFO, "couldn't find mouse pointer\n");
00265             s->mouse_warning_shown = 1;
00266         }
00267         *x = -1;
00268         *y = -1;
00269     }
00270 }
00271 
00283 static void inline
00284 apply_masks(uint8_t *dst, int and, int or, int bits_per_pixel)
00285 {
00286     switch (bits_per_pixel) {
00287     case 32:
00288         *(uint32_t*)dst = (*(uint32_t*)dst & and) | or;
00289         break;
00290     case 16:
00291         *(uint16_t*)dst = (*(uint16_t*)dst & and) | or;
00292         break;
00293     case 8:
00294         *dst = !!or;
00295         break;
00296     }
00297 }
00298 
00308 static void
00309 paint_mouse_pointer(XImage *image, struct x11_grab *s, int x, int y)
00310 {
00311     /* 16x20x1bpp bitmap for the black channel of the mouse pointer */
00312     static const uint16_t const mousePointerBlack[] =
00313         {
00314             0x0000, 0x0003, 0x0005, 0x0009, 0x0011,
00315             0x0021, 0x0041, 0x0081, 0x0101, 0x0201,
00316             0x03c1, 0x0049, 0x0095, 0x0093, 0x0120,
00317             0x0120, 0x0240, 0x0240, 0x0380, 0x0000
00318         };
00319 
00320     /* 16x20x1bpp bitmap for the white channel of the mouse pointer */
00321     static const uint16_t const mousePointerWhite[] =
00322         {
00323             0x0000, 0x0000, 0x0002, 0x0006, 0x000e,
00324             0x001e, 0x003e, 0x007e, 0x00fe, 0x01fe,
00325             0x003e, 0x0036, 0x0062, 0x0060, 0x00c0,
00326             0x00c0, 0x0180, 0x0180, 0x0000, 0x0000
00327         };
00328 
00329     int x_off = s->x_off;
00330     int y_off = s->y_off;
00331     int width = s->width;
00332     int height = s->height;
00333 
00334     if (   x - x_off >= 0 && x < width + x_off
00335         && y - y_off >= 0 && y < height + y_off) {
00336         uint8_t *im_data = (uint8_t*)image->data;
00337         int bytes_per_pixel;
00338         int line;
00339         int masks;
00340 
00341         /* Select correct masks and pixel size */
00342         if (image->bits_per_pixel == 8) {
00343             masks = 1;
00344         } else {
00345             masks = (image->red_mask|image->green_mask|image->blue_mask);
00346         }
00347         bytes_per_pixel = image->bits_per_pixel>>3;
00348 
00349         /* Shift to right line */
00350         im_data += image->bytes_per_line * (y - y_off);
00351         /* Shift to right pixel in the line */
00352         im_data += bytes_per_pixel * (x - x_off);
00353 
00354         /* Draw the cursor - proper loop */
00355         for (line = 0; line < FFMIN(20, (y_off + height) - y); line++) {
00356             uint8_t *cursor = im_data;
00357             int column;
00358             uint16_t bm_b;
00359             uint16_t bm_w;
00360 
00361             bm_b = mousePointerBlack[line];
00362             bm_w = mousePointerWhite[line];
00363 
00364             for (column = 0; column < FFMIN(16, (x_off + width) - x); column++) {
00365                 apply_masks(cursor, ~(masks*(bm_b&1)), masks*(bm_w&1),
00366                             image->bits_per_pixel);
00367                 cursor += bytes_per_pixel;
00368                 bm_b >>= 1;
00369                 bm_w >>= 1;
00370             }
00371             im_data += image->bytes_per_line;
00372         }
00373     }
00374 }
00375 
00376 
00387 static int
00388 xget_zpixmap(Display *dpy, Drawable d, XImage *image, int x, int y)
00389 {
00390     xGetImageReply rep;
00391     xGetImageReq *req;
00392     long nbytes;
00393 
00394     if (!image) {
00395         return 0;
00396     }
00397 
00398     LockDisplay(dpy);
00399     GetReq(GetImage, req);
00400 
00401     /* First set up the standard stuff in the request */
00402     req->drawable = d;
00403     req->x = x;
00404     req->y = y;
00405     req->width = image->width;
00406     req->height = image->height;
00407     req->planeMask = (unsigned int)AllPlanes;
00408     req->format = ZPixmap;
00409 
00410     if (!_XReply(dpy, (xReply *)&rep, 0, xFalse) || !rep.length) {
00411         UnlockDisplay(dpy);
00412         SyncHandle();
00413         return 0;
00414     }
00415 
00416     nbytes = (long)rep.length << 2;
00417     _XReadPad(dpy, image->data, nbytes);
00418 
00419     UnlockDisplay(dpy);
00420     SyncHandle();
00421     return 1;
00422 }
00423 
00431 static int
00432 x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt)
00433 {
00434     struct x11_grab *s = s1->priv_data;
00435     Display *dpy = s->dpy;
00436     XImage *image = s->image;
00437     int x_off = s->x_off;
00438     int y_off = s->y_off;
00439 
00440     int64_t curtime, delay;
00441     struct timespec ts;
00442 
00443     /* Calculate the time of the next frame */
00444     s->time_frame += INT64_C(1000000);
00445 
00446     /* wait based on the frame rate */
00447     for(;;) {
00448         curtime = av_gettime();
00449         delay = s->time_frame * av_q2d(s->time_base) - curtime;
00450         if (delay <= 0) {
00451             if (delay < INT64_C(-1000000) * av_q2d(s->time_base)) {
00452                 s->time_frame += INT64_C(1000000);
00453             }
00454             break;
00455         }
00456         ts.tv_sec = delay / 1000000;
00457         ts.tv_nsec = (delay % 1000000) * 1000;
00458         nanosleep(&ts, NULL);
00459     }
00460 
00461     if (av_new_packet(pkt, s->frame_size) < 0) {
00462         return AVERROR(EIO);
00463     }
00464 
00465     pkt->pts = curtime;
00466 
00467     if(s->use_shm) {
00468         if (!XShmGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off, AllPlanes)) {
00469             av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n");
00470         }
00471     } else {
00472         if (!xget_zpixmap(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off)) {
00473             av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n");
00474         }
00475     }
00476 
00477     {
00478         int pointer_x, pointer_y;
00479         get_pointer_coordinates(&pointer_x, &pointer_y, dpy, s1);
00480         paint_mouse_pointer(image, s, pointer_x, pointer_y);
00481     }
00482 
00483 
00484     /* XXX: avoid memcpy */
00485     memcpy(pkt->data, image->data, s->frame_size);
00486     return s->frame_size;
00487 }
00488 
00495 static int
00496 x11grab_read_close(AVFormatContext *s1)
00497 {
00498     struct x11_grab *x11grab = s1->priv_data;
00499 
00500     /* Detach cleanly from shared mem */
00501     if (x11grab->use_shm) {
00502         XShmDetach(x11grab->dpy, &x11grab->shminfo);
00503         shmdt(x11grab->shminfo.shmaddr);
00504         shmctl(x11grab->shminfo.shmid, IPC_RMID, NULL);
00505     }
00506 
00507     /* Destroy X11 image */
00508     if (x11grab->image) {
00509         XDestroyImage(x11grab->image);
00510         x11grab->image = NULL;
00511     }
00512 
00513     /* Free X11 display */
00514     XCloseDisplay(x11grab->dpy);
00515     return 0;
00516 }
00517 
00519 AVInputFormat x11_grab_device_demuxer =
00520 {
00521     "x11grab",
00522     NULL_IF_CONFIG_SMALL("X11grab"),
00523     sizeof(struct x11_grab),
00524     NULL,
00525     x11grab_read_header,
00526     x11grab_read_packet,
00527     x11grab_read_close,
00528     .flags = AVFMT_NOFILE,
00529 };