PNG and Web Design

[tdtaylor]

Does anyone know of any pitfalls for using PNG's on web pages? Also, how do they differ from the ever-popular GIF format? I know that both support transparency, and I know that both load faster than JPG. Also, I have been informed that PNG is recognized by all browsers, though the format isn't used as widely as GIF and JPG.

Any comments or suggestions?

[Rick Bull]

PNG is a great format. You can have alpha transparency (so proper shadows and the like, blending into whatever colour the background is (although IE doesn't support it )), gamma support (so it looks the right colour on other platforms like Mac), better interlacing (you see a "preview" of the image faster, and it updates more often), true colour and lossless. Probably some more that I can't remember right now. Browser support is pretty good too. NS 4.x supports it (although has some bugs with transparency). I use pretty much only PNG.

[jeffmott]

and I know that both load faster than JPG

You should not characterize this as a general rule. JPEG will better compress images with many changing colors (real life pictures, gradients, etc.). GIF and PNG are better at compressing images made of areas of solid colors. PNG is, however, most certainly a better format than GIF.

[tdtaylor]

Thanks, guys. Most helpful, indeed. I don't know that I will be dealing much with transparency if I don't have to, especially with .png. If I need transparency, I will most likely rely on .gif images to help me with that because I know I can trust it with the browsers.

However, I do believe I will try using .png for some backgrounds and other images that contain a large area of one color.

Again, thanks a bunch!

[Klyve1]

PNG will become a much better supported format now that GIF compression is no longer free.

[Rick Bull]

I thought that never happened, and it was just talk? Hopefully more browsers will support MNG too, so we can have animated PNGs. Currently I think Mozilla is the only browser that supports it natively.

[Klyve1]

I've not seen any MNG files but I was getting my info re GIFs from GNU related sites like http://www.gnu.org/philosophy/gif.html and http://lpf.ai.mit.edu/Patents/Gif/Gif.html

[Stefan]

Originally posted by tdtaylor
If I need transparency, I will most likely rely on .gif images to help me with that because I know I can trust it with the browsers.

GIF only support 1 bit transparency (transparent or not). 1-bit transparency works just fine crossbrowser also with PNG.

However PNG can allow you to use for advanced 8bit transparency, and this is what causes buggy IE to stumble and fall. Mozilla as well as Opera has supported 8-bit transparancy for years now.

In short, there is absolutely nothing to gain by sticking to GIF.

[bpm125]

Originally Posted by Klyve1

PNG will become a much better supported format now that GIF compression is no longer free.

What do you mean that .gif compression is now no longer free? Are we gonna have to pay extra to create .gif files now? Are .gif files no longer being used?

[Klyve1]

Originally Posted by bpm125

What do you mean that .gif compression is now no longer free? Are we gonna have to pay extra to create .gif files now? Are .gif files no longer being used?

No, the owners of the .gif format now charge software makers a licence fee to use it in their products.

As this topic is some 5 years old it obviously hasn't had any effect at all!