Name
XvGetStill - capture a single frame of video from a drawable
Syntax
include Xvlib.h
XvGetStill(_d_p_y_, _p_o_r_t_, _d_, _g_c_, _v_x_, _v_y_, _v_w_, _v_h_, _d_x_, _d_y_, _d_w_, _d_h)
register
Display
*dpy;
XvPortID
port;
Drawable
d;
GC
gc;
int
vx,
vy,
dx,
dy;
unsigned int
vw,
vh;
unsigned int
dw,
dh;
Arguments
-
_d_p_y
Specifies the display screen on which the
-
Xv Server is to accept requests from Xv clients. If the
display option is not specified, Xv uses the display screen
specified by your DISPLAY environment variable. The display
option has the format hostname:number. Using two colons
(::) instead of one (:) indicates that DECnet is to be used
for transport.
-
_p_o_r_t
Defines the port to which the still is output'd.
-
-
_d
Defines the drawable from which the still is to be captured.
-
Pixmaps are currently not supported.
-
_g_c
Defines the graphical context. GC components are:
-
subwindow-mode,
clip-x-origin,
clip-y-origin,
and
clip-mask.
-
_v_x_,_v_y_,_v_w_,_v_h
Define the location and size of the destination video region
-
into which the still is to be written. _v_x and _v_y define the
x and
y
coordinates of the upper-left corner of the video region;
vw and
vh
define the width and height, in pixels, of the video region.
-
_d_x_,_d_y_,_d_w_,_d_h
Define the location and size of the source drawable from which the
-
still image is to be captured.
dx and
dy
define the
x and
y
coordinates of the upper-left corner of the drawable region;
dw and
dh
define the width and height, in pixels, of the drawable region.
Description
captures a single frame of video from a drawable. The
position and size of the destination (video) rectangle is specified by _v_x_,
_v_y_, _v_w, and _v_h. The position and size of the
source (drawable) rectangle is
specified by _d_x_, _d_y_, _d_w, and _d_h.
Drawable data is clipped to the bounds of the drawable, scaled to the
requested video region size (or the closest size supported) and
clipped to the bounds of the video encoding. The contents of any region
not updated with drawable data is undefined.
If the port is grabbed
by another client, this request is ignored, and an XvVideoNotify event
with detail XvBusy is generated for the drawable.
Returned Values
-
[Success]
Returned if XvGetStill(3X) completed successfully.
-
-
[XvBadExtension]
Returned if the Xv extension is unavailable.
-
-
[XvBadAlloc]
Returned if XvGetStill(3X) failed to allocate memory to process
-
the request.
Diagnostics
-
[XvBadPort]
Generated if the requested port does not exist.
-
-
[BadDrawable]
Generated if the requested drawable does not exist.
-
-
[BadGC]
Generated if the requested graphics context does not exist.
-
-
[BadAlloc]
Generated if there were insufficient resources to process the request.
-
See Also
XvPutStill(3X), XvGetVideo(3X), XvPutVideo(3X), XvVideoNotify(3X)