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Rare Jon 'maddog' Hall video interview - and an even rarer maddog video speech excerp
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Xv(3) Library Functions Manual 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 independent 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 draw- able 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, according 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)
