diff --git a/doc/ffmpeg-doc.texi b/doc/ffmpeg-doc.texi index d9d30ee7f4..470cfe3c10 100644 --- a/doc/ffmpeg-doc.texi +++ b/doc/ffmpeg-doc.texi @@ -50,6 +50,13 @@ ffmpeg -f x11grab -vd x11:0.0 /tmp/out.mpg 0.0 is display.screen number of your X11 server, same as the DISPLAY environment variable. +@example +ffmpeg -f x11grab -vd x11:0.0+10,20 /tmp/out.mpg +@end example + +0.0 is display.screen number of your X11 server, same as the DISPLAY environment +variable. 10 is the x-offset and 20 the y-offset for the grabbing. + @section Video and Audio file format conversion * FFmpeg can use any supported file format and protocol as input: diff --git a/libavformat/x11grab.c b/libavformat/x11grab.c index 4b237f6c26..48ef3d7256 100644 --- a/libavformat/x11grab.c +++ b/libavformat/x11grab.c @@ -94,20 +94,33 @@ x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap) int x_off = 0; int y_off = 0; int use_shm; - - dpy = XOpenDisplay(NULL); - if(!dpy) { - av_free(st); - return AVERROR_IO; - } + char *param, *offset; if (!ap->device) { av_log(s1, AV_LOG_ERROR, "AVParameters don't specify any device. Use -vd.\n"); return AVERROR_IO; } - sscanf(ap->device, "x11:%d,%d", &x_off, &y_off); - av_log(s1, AV_LOG_INFO, "device: %s -> x: %d y: %d width: %d height: %d\n", ap->device, x_off, y_off, ap->width, ap->height); + param = strchr(ap->device, ':'); + if (!param) { + av_free(st); + return AVERROR_IO; + } + + param = av_strdup(param); + offset = strchr(param, '+'); + if (offset) { + sscanf(offset, "%d,%d", &x_off, &y_off); + *offset= 0; + } + + av_log(s1, AV_LOG_INFO, "device: %s -> display: %s x: %d y: %d width: %d height: %d\n", ap->device, param, x_off, y_off, ap->width, ap->height); + + dpy = XOpenDisplay(param); + if(!dpy) { + av_log(s1, AV_LOG_ERROR, "Could not open X display.\n"); + return AVERROR_IO; + } if (!ap || ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) { av_log(s1, AV_LOG_ERROR, "AVParameters don't have any video size. Use -s.\n");