If the file is a PNG image file (see Portable_Network_Graphics) then a better technique is probably to actually parse the file to find the chunk of interest then simply extract the chunk. The Wikipedia article gives all the information you need to understand the file format and a little playing around with read, unpack and seek should give you the main tools you need to write the code.

Premature optimization is the root of all job security

In reply to Re: Weird file extraction problem by GrandFather
in thread Weird file extraction problem by knight.of.ni

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