Xv(3)Xv(3)NameXv - 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)
