Image formats & metadata


Hope you don’t mind, but I’m responding to your post in “The case of the missing COMMENT” here, lest we incur the wrath of the admins for straying too far from the original topic.

I use PNG because it’s compressed but lossless, and I can (currently) upload 32-bit PNGs to my Google Photos account without having them count against my combined Google account free storage limit of 15 GB (reportedly, ALL image uploads to Google Photos after some date in June of this year will count against the free storage limit). I experimented with TIFF a bit some years ago, but didn’t see any way to save them with LZW or other compression from any of the tools I commonly use (mostly Corel PaintShop Pro and GIMP), and am not in a position to shell out for Photoshop or other “professional-level” applications. Also, as great as DOpus is, I can’t use it natively to convert to TIFF.

If you have any other suggestions, I’m open.

Here I am pretending I'm going to save a TIFF from within Irfanview.



Cool, thanks. I just recently started using IrfanView as a viewer.

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I see someone has pointed you to a program that can make LZW Tiffs and does not cost a fortune like Photoshop.

My understanding of LZW compression is that it was written in the mid 1970s and is owned by Unisys from whom software companies wanting to use it have to buy a licence.

It is apparently widely used processing PDFs and text based files, which apparently compress well with its algorithms. It is also lossless and supports transparency.

Reading this may update you on the current state of things regarding licensing. (Also, it was released in the 80s, not 70s.)

Wikiwand is a nicer-looking (in my opinion) mirror of Wikipedia. Here's the article on Wikipedia: