Why Do Downloaded Pics Change Formats?

[b4icu]

Confused yet? What I mean is to say that when I am downloading pictures from a website, on one visit they will be in Jpeg format. But on occasion, when I return to the same website, the next time the pictures will download to my computer in GIF format (which is less preferable due to their larger sizes). The kick in the pants is that if I return to the same website another day, and download the same pictures, they will be back to Jpeg format again!

So my question is this...do websites sometimes change the format of their pictures from time to time, or would this be the result of something gone haywire on my machine? And, has anyone else noticed this?

b4

ps. strange question for the general filesharing forum i know, but I share all of these pictures with the network, hehe.

[Mystikan]

I've never encoutered this phenomenon. Are you sure you're clicking on the same picture on the same page each time? The site might have the same picture in two places, for example as a link image in GIF and then the actual image in JPEG. If you are clicking the same one, I'd say it's a result of the webmaster changing the format, though I couldn't think why they'd do that. JPEG is generally used for pictures with many different colours, such as photographs, while GIF is usually used for low-colour pictures, such as Web buttons and company logos. Could you post a link to the site that's doing this, so I can have a looksee? If so, I'll see what I can find out.

[b4icu]

It has happened on a variety of sites such as DOMAI, playboy.espanol, http://googirl.com.ar/googirl/directory/TV.../International/ (http://googirl.com.ar/googirl/directory/TV_Stars/International/) , etc. But the frequency of occurance is so low (once a month or less) that it almost certainly wont happen if u check it out. It just happened yesterday though. Its really no big deal, as acdsee can mass convert the GIFs to Jpegs in short order, but really makes me curious why it happens in the first place.