Xv(3) Xv(3)
Name
Xv - X Window System video extension
Description
The Xv extension provides support for video adaptors attached to an X
display. It takes the approach that a display may have one or more
video adaptors, each of which has one or more ports through which inde-
pendent video streams pass.
An adaptor may be able to display video in a drawable, capture video
from a drawable, or both. It translates between video encoding (NTSC,
PAL, SECAM, etc...) and drawable format (depth and visual-id pair). An
adaptor may support multiple video encodings and/or multiple drawable
formats.
Clients use Xv(3) to gain access and manage sharing of a display's
video resources. Typically, a client will use XvQueryExtension(3) to
determine the status of the extension, XvQueryAdaptors(3) to get a
description of what video adaptors exist, and XvQueryEncodings(3) to
get a description of what video encodings an adaptor supports.
Once a client has determined what video resources are available, it is
free to put video into a drawable or get video from a drawable, accord-
ing the capabilities supported. Clients can select to receive events
when video activity changes in a drawable and when port attributes have
changed.
Summary of Library Functions
The following is a summary of Xv library functions:
XvGetPortAttribute(3) - return current port attribute value
XvGetStill(3) - capture a single frame of video from a drawable
XvGetVideo(3) - capture video from a drawable
XvGrabPort(3) - lock port for exclusive use by client
XvPortNotify(3) - event generated when port attributes change
XvPutStill(3) - write a single frame of video to a drawable
XvPutVideo(3) - write video into a drawable
XvQueryAdaptors(3) - return adaptor information for a screen
XvQueryBestSize(3) - determine the optimum drawable region size
XvQueryEncodings(3) - return list of encodings for an adaptor
XvQueryExtension(3) - return version and revision of extension
XvSelectPortNotify(3) - enable or disable XvPortNotify events
XvSelectVideoNotify(3) - enable or disable XvVideoNotify events
XvSetPortAttribute(3) - set an attribute for a port
XvStopVideo(3) - stop active video
XvUngrabPort(3) - release a grabbed port
XvVideoNotify(3) - event generated for video processing
Each of these functions is described in its own Xv man page.
X Version 11 libXv 1.0.4 Xv(3)
Mac OS X 10.6 X11 - Generated Sun Mar 7 12:33:21 CST 2010