TIFF and GIF files may contain more than one image. The FrameCount
property reflects the number of images found in the file. You can
select different images using the Frame
property.
Multi-frame TIFF images are generally used for one of two purposes.
Sometimes multiple copies of the same image are embedded at different
sizes to allow previews to be obtained quickly and easily. This
type of multi-frame image is generally created for print purposes.
Sometimes multiple pages of a document may be embedded in a TIFF.
This type of multi-frame image is generally created by document
scanning software or fax software.
Multi-frame GIF images are often called animated GIFs. Each image
represents a frame of the animation. Similarly Flash / SWF movies
are frame based and this property allows you to access the total
number of frames in the movie.
PostScript is a programming language. So a PostScript program may
output a different number of pages each time it is run. For this
reason it is not possible to reliably determine the number of pages
in a PostScript file until it is actually displayed. As a result
EPS and PS files always have a FrameCount of one no matter how many
pages they may display. However it is reasonably safe to assume
that EPS files only ever contain one page of content.
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