Image size/ratio question Options

[CharlesEF]

Hi All,

I'm looking for advise on how to handle the next phase of my project. I'm working with images (lets say country flags) and I have 1 main image, about 180 x 100. Not all flags are the same size and some flags have a different ratio when compared to other flags (some are wider, some are higher).

1. If I want to display a smaller version of a flag must I generate an image with the size I want OR can I just write the <img> tag with the size I want?
2. How can I know what size the original image is so I can write the <img> tag in a size that maintains the flag ratio? Is there some way to read this information off the server or do I have to maintain a list of each image size?

I will be using .png when I can otherwise I will use .gif format. Or, am I totally off base with my idea? Can anyone suggest a better way?


Thanks for any ideas,

Charles