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Read zTXt chunk of a PNG.

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How would I go about this? I already got code which gets the data as an ArrayBuffer and a Uint8Array.

I can read all the bytes fine, until I get up to the compressed data in which I just don't know what to do.

How would I go about decompressing this data so I can actually read it?

***This should be done using client-side javascript code, I don't want my server to have to do anything to read the chunk from the file.

EDIT: This is a link to info about the zTXt chunk I need to decompress.

http://www.w3.org/TR/PNG/#11zTXt

It seems to mention I need to use zLib deflate compression to handle the file, but I can't find anything on how that works.

I have found libs that handle this, but i'd rather not use a pre-made lib for this purpose, I want to understand how the compression works and be able to do it myself, but nothing seems to mention how zlib deflation works.


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