Incorrect decompression of iTXt compressed chunk

[hbs]

The included image contains an iTXt chunk with compressed text. The text as included in the image is below (between ---8<---), but the text reported by UPNG.js is truncated.

---8<--- 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---8<---

[photopea]

Hi, I fixed it, thanks for reporting :)

[hbs]

Hi, the fixed version works on the image provided with the issue but fails with this new image.

[photopea]

I fixed it again :)

[hbs]

I encountered yet another issue and fixed it by changing the 5 in 6! Any chance the unminified code lies somewhere? Does it come from pako?

[photopea]

The minified code is actually our library UZIP.js

The problem is, that when you see a compressed text of X bytes in "iTXt", it is not clear, how long is the decompressed text. Our decompressor, in order to be fast, tries to allocate a sufficiently long array just once, before the decompression.

Another method would be to start decompressing into an array of 1 Byte, and after each byte decoded, check, if we need to increase the size of an array.