ImageGlue supports movie as well as image formats. By default
movie processing is disabled because the load placed on a web
server may be rather higher than that for image processing. You can
enable movie handling using IGSettings.
ImageGlue supports most of the standard QuickTime movie formats.
These include Movie (MOV), AVI, Flash 4.0 (SWF) and SMIL. SMIL is a
particularly convenient store because as XML it can be simply
generated and then used for compositing operations saved out via
ImageGlue.
Movies are handled almost exactly the same way as any other
image media. You can use standard calls like Canvas.DrawFile or
Graphic.SetData to assign movies in exactly the same way you would
any still image media.
The concept of images is not very useful when processing movies.
Movies often contain multiple tracks playing at different frame
rates or tracks playing at a variable frame rate. If you want to
draw an image from the middle of a movie you should use the Time
rather than the Image parameter.
When drawing images from movies you can specify a URL rather
than a file path. This allows you to capture images from internet
based or streaming video. ImageGlue supports HTTP, FTP and RTSP
URLs. Note that this feature is not suitable for high load
servers.
Because of the size of movies it is not a good idea to draw them
direct from memory. ImageGlue copies all in-memory movies to disk
before decoding the required image. This means that if you need to
process in-memory movies using calls like Canvas.DrawData, the
internet user - IUSR - will require full access to the temp
directory. If the security permissions are not available ImageGlue
may return a file related error.
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