xTalk JPEG parser?

[Stephen Quinn Barncard]

I've tried. I've downloaded the specs and tried to follow them but I 
couldn't get my code to reliably work on every JPEG. It's harder than 
it looks.

Basically the numbers are in jump tables after the beginning of the 
file, but there's a few things in the spec I couldn't figure out. 
There used to be an XCMD for that in HC days, and I know it's 
possible... I gave up after a while. Also there's new additions to 
the spec : EXIF which deals with camera info.

THere are some fixed bytes at the beginning of the file that point to 
the next header, then another jump, and another until the end of the 
headers.

Some attempts were based on simple PERL code examples I found on the 
net, but those didn't work well reliably. There's something missing 
in the info...


>Has anyone written parser in xTalk that will parse a JPEG file and 
>get things like the dimensions, EXIF info, etc.?
>
>Thanks,
>-- Frank