Economy and Image Formats . . .

[Colin Holgate]

On Nov 1, 2008, at 9:14 AM, Richmond Mathewson wrote:

> I have never had a problem with GIF images on Ubuntu, and so really  
> don't see why using PNG format would be a tremendous advantage.

GIFs are up to 256 colors, and you'll get a dither of colors if the  
original image uses more colors than that. PNG can be 8 bit or 24 bit.  
How much compression you get will depend on the size of large flat  
colored areas, it's not like JPEG where the quality of the image is  
lowered to get smaller sizes, with PNG it's going to be a particular  
size.

So, you would use PNGs if having the picture looking good is the most  
important thing, or if the image has alpha transparencies in it (not  
just transparent or not transparent as with GIF, but degrees of  
transparency).

Depending on the nature of the image, JPEG may well be a better option  
than either PNG or GIF.