Best File Format for Tranparency in Orphalese

[Greg the Yeti]

Having just spent quite some time ironing out problems with Transparent Decks I've created, I thought it would be a good idea to start a discussion about the best format to use.
GIF and PNG seem the most popular, but JPG is also possible.

I've now used three different file formats. All work but here are my observations.
I'm creating the cards in CorelDRAW, a Vector Format Program, and then exporting them with "Anti-Aliasing" turned OFF (Because it wrecks the effect!)

jpg) Yes it "works" by the creator using a solid colour for the border to the card, which is then made transparent. HOWEVER - I found that with a test with a very pure Red lettering on a perfectly pure background that exporting from my Vector Graphics Program to jpg resulted in inbetween colour tones near the edge. This must be a part and parcel of the jpg "compression" method? These inbetween tones, wreck the transparency, because Orphalese does not remove them! I won't use jpg for Transparency again!!

png) I've seen a few examples of this used for transparency and read people saying to use it. The format supports "Transparency" - but Orphalese does not require the files to support transparency. So it works - whether you use transparency or a solid colour for the border.
However I noticed that for a given file size the png's were of a lower image quality than either gif or jpg.
So, if file size is an issue then Don't use png!

gif) I've seen quite a few Transparent Decks that use this, and now have created a good few myself. Once again it works with Orphalese's transparency function - whether you use transparency within the files or not!
I've found that on the Decks where I tried this, that the gif file format produced the best image results for any given file size. (Or put that another way, for a given quality of image, the files are smaller) than either of the above two formats.
I'll ONLY be using gif format - unless someone can persuade me otherwise!

Please comment if you have experience of knowledge in this area. Other people might benefit as well as me!

Regards
Greg the Yeti

P.S. A further note about file formats - FILE CORRUPTION:-
And I'm not talking about "naughty" Decks!
I've noticed that jpg's seem to be particularly prone to File Corruption problems. Has anybody else noticed this? It appears as partial horizontal lines where the image is lost. Sometimes this results in the two parts of the image being staggered.
I've also seen File Corruption with both the other formats discussed here. The "style" of fault is different. They don't seem to share jpg's specific problem. Also they don't SEEM to be corrupted quite so often...

Any comments?

[Greg the Yeti]

With regard to that last comment about File Corruption:-

I have SO many of my own photos in jpg format (a good number of GB!) that I've taken to making sure that I have several backups so that if any are corrupted I hope that I have a copy that's good. I do the same with my Orphalese Decks!

What I would LIKE, if anybody here knows, is a utility that could automatically scan for Image file corruption. If it could attempt repairs, even better.

I did buy a utility that I thought would do this, but it turned out that it was for editing scratches and damage to real photos that you had scanned in and NOTHING to do with File Corruption. I returned the software under their terms of aggreement, for a full refund.

Greg the Yeti