Corrupt PNG files after unzipping

I downloaded 7-zip for Windows to extract .png files from .deb archives, but they turn out corrupted, showing a black background instead. Is there an alternative, working program for unzipping .deb archives for Windows or perhaps a way around this?

Thx

Solution 1:

Debian packages contains tarballs that are optionally compressed with gzip, bzip2, lzma or xz.

7-Zip handles all of these formats just fine. Anyway, if only the background of the PNG changed, it is very unlikely that the file archiver is at fault. The problem probably lies somewhere else, possibly in the program you're viewing the PNG file with.

If you want to try another file archiver anyway, you don't have a lot to chose from. I found AnyToISO with Google, but I haven't tried it.

Solution 2:

Since your image appears to be correct except for the background color, the image most likely not corrupted.

A black background in the transparent regions of a PNG are most often caused by the viewing application you use, or by the application used to export the image to disk. The application is apparently not capable of displaying the transparency correctly.

As PNG pixels consists of four color values (Red, Green, Blue and Alpha, RGBA), any viewer or editing application that ignores the alpha component will just display the remaining color components. If those RGB components are all set to 0, the resulting color is black.