New Post: Detect best save format PNG or JPG

The image will be used for web viewing.

I was hoping the pure vector files and clip art could be saved as PNG, Photos as JPG.

If the user uploaded a SVG that has an embedded image then i guess JPG would be the best.

Just trying to work out if there is a way to detect the type and go from there.

Maybe counting the numbers of colors if that's possible...