Re: Raw JPEG Data Size

>I have a raw stream of data, part of which contains a JPEG (possibly
> not in its entirity). I am attempting to extract (just extract, not
> interpret) the image. Currently I detect the JPEG (JFIF) signature,
> then walk through the image for as long as possible by detecting valid
> headers and their size. Unfortunately, once I reach the start of a
> scan (M_SOS) I am lost as to how to detect the correct/appropriate
> size. I could attempt to scan for M_EOI however, this is extremely
> unreliable as a) it may occur in data (?) and b) there is the
> possiblity it will not be there at all and my extraction will never
> end. I am not very versed in the ways of JPEG and any help on this
> matter will be great. I have looked over IJG's code on the subject and
> it seems rather advanced for what I am trying to do. Is there any
> simple calculations I can use to get the size of the scan or the
> distance from any unique marker to M_EOI?

no, just scan file for 0xFFE9

--
Andrey Kuznetsov
http://uio.imagero.com Unified I/O for Java
http://reader.imagero.com Java image reader
http://jgui.imagero.com Java GUI components and utilities


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