[BUG] Flash file JPEG decoding

Tim Olson tim at jump.net
Tue Jun 12 13:00:45 UTC 2001

I've debugged this problem a little more.  Ignoring the extraneous EOI, 
SOI on the front, it appears to be a valid JFIF image.  However, the 
FlashJPEGDecoder (a subclass of JPEGReadWriter) is performing the Flash 
tag 21 "ProcessDefineBitsJPEG2", which reads a JFIF header, parsing the 
JFIF markers while looking for an EOI marker (i.e. it seems to be 
expecting just a JFIF header with no JPEG image data following it).

I'm not sure what the real purpose of ProcessDefineBitsJPEG2 is, as after 
it reads the JFIF header and an expected EOI, it then performs 
decodeNextImageFrom:, which would then process an entire JFIF image 
(including parsing all the header data from the stream again, in effect 
discarding the header data previously read).

I think Andreas Raab was the person who implemented the Flash support -- 
Andreas, do you have any insights into what is going on in this case?

     -- tim

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