forcing a format when emitting a blob?

If I want to emit a GIF as a blob from an Image, it appears I need to set
image->magick to what I guess is an enumerated value. The example says
"GIF". I'm looking through the headers and not finding the enumeration,
and nothing in the docs. Pointers?

-bch

-- 
Brad Harder
Method Logic Digital Consulting
http://methodlogic.net/
http://twitter.com/bcharder


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