diff --git a/doc/ffmpeg.texi b/doc/ffmpeg.texi index 4dca5d8991..8d3968dbf2 100644 --- a/doc/ffmpeg.texi +++ b/doc/ffmpeg.texi @@ -900,8 +900,21 @@ the DISPLAY environment variable. ffmpeg -f x11grab -s cif -r 25 -i :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. +10 is the x-offset and 20 the y-offset for the grabbing. + +@example +ffmpeg -f x11grab -follow_mouse centered -s cif -r 25 -i :0.0 /tmp/out.mpg +@end example + +The grabbing region follows the mouse pointer, which stays at the center of +region. + +@example +ffmpeg -f x11grab -follow_mouse 100 -s cif -r 25 -i :0.0 /tmp/out.mpg +@end example + +Only follows when mouse pointer reaches within 100 pixels to the edge of +region. @section Video and Audio file format conversion diff --git a/doc/indevs.texi b/doc/indevs.texi index c5e04b029e..aa001cdb63 100644 --- a/doc/indevs.texi +++ b/doc/indevs.texi @@ -248,7 +248,27 @@ For example to grab from @file{:0.0} using @file{ffmpeg}: ffmpeg -f x11grab -r 25 -s cif -i :0.0 out.mpg # Grab at position 10,20. -ffmpeg -f x11grab -25 -s cif -i :0.0+10,20 out.mpg +ffmpeg -f x11grab -r 25 -s cif -i :0.0+10,20 out.mpg +@end example + +@subsection @var{follow_mouse} AVOption + +The syntax is: +@example +-follow_mouse centered|@var{PIXELS} +@end example + +When it is specified with "centered", the grabbing region follows the mouse +pointer and keeps the pointer at the center of region; otherwise, the region +follows only when the mouse pointer reaches within @var{PIXELS} (greater than +zero) to the edge of region. + +For example: +@example +ffmpeg -f x11grab -follow_mouse centered -r 25 -s cif -i :0.0 out.mpg + +# Follows only when the mouse pointer reaches within 100 pixels to edge +ffmpeg -f x11grab -follow_mouse 100 -r 25 -s cif -i :0.0 out.mpg @end example @c man end INPUT DEVICES diff --git a/libavdevice/x11grab.c b/libavdevice/x11grab.c index 80507abb05..0b865ad71e 100644 --- a/libavdevice/x11grab.c +++ b/libavdevice/x11grab.c @@ -71,6 +71,7 @@ struct x11_grab int use_shm; /**< !0 when using XShm extension */ XShmSegmentInfo shminfo; /**< When using XShm, keeps track of XShm infos */ int draw_mouse; /**< Set by a private option. */ + int follow_mouse; /**< Set by a private option. */ char *framerate; /**< Set by a private option. */ }; @@ -95,6 +96,7 @@ x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap) XImage *image; int x_off = 0; int y_off = 0; + int screen; int use_shm; char *param, *offset; int ret = 0; @@ -141,6 +143,22 @@ x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap) } av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */ + screen = DefaultScreen(dpy); + + if (x11grab->follow_mouse) { + int screen_w, screen_h; + Window w; + + screen_w = DisplayWidth(dpy, screen); + screen_h = DisplayHeight(dpy, screen); + XQueryPointer(dpy, RootWindow(dpy, screen), &w, &w, &x_off, &y_off, &ret, &ret, &ret); + x_off -= x11grab->width / 2; + y_off -= x11grab->height / 2; + x_off = FFMIN(FFMAX(x_off, 0), screen_w - x11grab->width); + y_off = FFMIN(FFMAX(y_off, 0), screen_h - x11grab->height); + av_log(s1, AV_LOG_INFO, "followmouse is enabled, resetting grabbing region to x: %d y: %d\n", x_off, y_off); + } + use_shm = XShmQueryExtension(dpy); av_log(s1, AV_LOG_INFO, "shared memory extension %s found\n", use_shm ? "" : "not"); @@ -171,7 +189,7 @@ x11grab_read_header(AVFormatContext *s1, AVFormatParameters *ap) goto out; } } else { - image = XGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)), + image = XGetImage(dpy, RootWindow(dpy, screen), x_off,y_off, x11grab->width, x11grab->height, AllPlanes, ZPixmap); @@ -374,6 +392,10 @@ x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt) int x_off = s->x_off; int y_off = s->y_off; + int screen; + Window root; + int follow_mouse = s->follow_mouse; + int64_t curtime, delay; struct timespec ts; @@ -400,12 +422,43 @@ x11grab_read_packet(AVFormatContext *s1, AVPacket *pkt) pkt->size = s->frame_size; pkt->pts = curtime; + screen = DefaultScreen(dpy); + root = RootWindow(dpy, screen); + if (follow_mouse) { + int screen_w, screen_h; + int pointer_x, pointer_y, _; + Window w; + + screen_w = DisplayWidth(dpy, screen); + screen_h = DisplayHeight(dpy, screen); + XQueryPointer(dpy, root, &w, &w, &pointer_x, &pointer_y, &_, &_, &_); + if (follow_mouse == -1) { + // follow the mouse, put it at center of grabbing region + x_off += pointer_x - s->width / 2 - x_off; + y_off += pointer_y - s->height / 2 - y_off; + } else { + // follow the mouse, but only move the grabbing region when mouse + // reaches within certain pixels to the edge. + if (pointer_x > x_off + s->width - follow_mouse) { + x_off += pointer_x - (x_off + s->width - follow_mouse); + } else if (pointer_x < x_off + follow_mouse) + x_off -= (x_off + follow_mouse) - pointer_x; + if (pointer_y > y_off + s->height - follow_mouse) { + y_off += pointer_y - (y_off + s->height - follow_mouse); + } else if (pointer_y < y_off + follow_mouse) + y_off -= (y_off + follow_mouse) - pointer_y; + } + // adjust grabbing region position if it goes out of screen. + s->x_off = x_off = FFMIN(FFMAX(x_off, 0), screen_w - s->width); + s->y_off = y_off = FFMIN(FFMAX(y_off, 0), screen_h - s->height); + } + if(s->use_shm) { - if (!XShmGetImage(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off, AllPlanes)) { + if (!XShmGetImage(dpy, root, image, x_off, y_off, AllPlanes)) { av_log (s1, AV_LOG_INFO, "XShmGetImage() failed\n"); } } else { - if (!xget_zpixmap(dpy, RootWindow(dpy, DefaultScreen(dpy)), image, x_off, y_off)) { + if (!xget_zpixmap(dpy, root, image, x_off, y_off)) { av_log (s1, AV_LOG_INFO, "XGetZPixmap() failed\n"); } } @@ -452,6 +505,9 @@ static const AVOption options[] = { { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), FF_OPT_TYPE_STRING, {.str = "vga"}, 0, 0, DEC }, { "framerate", "", OFFSET(framerate), FF_OPT_TYPE_STRING, {.str = "ntsc"}, 0, 0, DEC }, { "draw_mouse", "Draw the mouse pointer.", OFFSET(draw_mouse), FF_OPT_TYPE_INT, { 1 }, 0, 1, DEC }, + { "follow_mouse", "Move the grabbing region when the mouse pointer reaches within specified amount of pixels to the edge of region.", + OFFSET(follow_mouse), FF_OPT_TYPE_INT, { 0 }, -1, INT_MAX, DEC, "follow_mouse" }, + { "centered", "Keep the mouse pointer at the center of grabbing region when following.", 0, FF_OPT_TYPE_CONST, { -1 }, INT_MIN, INT_MAX, DEC, "follow_mouse" }, { NULL }, };