PNG - why we use it more?

[lau3]

I am interested in starting a thread on your experiences with PNG and why we spend so much time talking about JPG and GIF if PNG is so superior. I would like to hear postivie and horror stories particularly with output to the web.

I know about the older browser limitation, but that should be as much an issue anymore. Is there significant use of Netscape and IE 3 anymore that we need to stay with older image formats?

Milt

[lau3]

I am interested in starting a thread on your experiences with PNG and why we spend so much time talking about JPG and GIF if PNG is so superior. I would like to hear postivie and horror stories particularly with output to the web.

I know about the older browser limitation, but that should be as much an issue anymore. Is there significant use of Netscape and IE 3 anymore that we need to stay with older image formats?

Milt

[gwpriester]

Milt

I find that PNG files are generally a lot larger in terms of file size, so I usually stick to GIFs for flat graphics and JPEG for photos or images with lots of subtle blends and bevels, shadows and stuff.

Gary

Gary Priester

Moderator Person

<a href="http://home.earthlink.net/~garypriester">
he tub mob relieves</a>

[Mickie]

I just recently had to prepare some graphics - gradient fills no bitmaps involved - and export for three different formats.

The gif was 4.19k (transparent)
The jpg was 4.3k
The Png was 3.6k (transparent)

Like everything else, it probably depends on whats involved in the graphic, but I was pleasantly surprised at the png.

Mickie

[pduggan]

For a run-down on what's wrong with GIFs, see http://www.burnallgifs.org. PNGs tend to be smaller for 'flat' graphics, but animations may still be a problem (so where's the support for MNGs?). True colour PNGs look very clean but can't compete with JPEGs for file size, so JPEGs still rule for web work with photos etc. Transparent PNGs don't seem to display transparency in Netscape 4.x, but not much works properly with that browser anyway! My site contains as few GIFs as possible (mostly just animations), with PNGs preferred for both file size and on principle.

Peter</p>

Peat Stack or Pete's Tack?</p>

[This message was edited by Peter Duggan on August 24, 2001 at 11:46.]

[Oystein]

Macromedia Fireworks use by default png-fils as projectfiles, but when exporting to web - the solution is jpeg/gif, they suggest jpeg/gif because of support and filesizes. They say in their manual that "The PNG-format is best for creating complex live transparency, high color graphics, and better compressed low-color graphics".

[Erik Heyninck]

True Oystein,

but Fireworks uses its own "PNG" if I'm not mistaken.


Peter: sorry, but there is something I do not understand. Does it mean that, even if you have used a prog that has a licence for GIF, you, as user will have to pay too? [img]/infopop/emoticons/icon_confused.gif[/img]

If you don't work against time, time often works for you.

[gwpriester]

<BLOCKQUOTE><font size="-1">quote:</font><HR> but Fireworks uses its own "PNG" if I'm not mistaken. <HR></BLOCKQUOTE>

Yeah. Everything that is saved in Fireworks is saved with the PNG extension and yet the elements are all editable. So it make one wonder if perhaps it is not a PNG at all but the Fireworks native file format?

Gary

Gary Priester

Moderator Person

<a href="http://home.earthlink.net/~garypriester">
he tub mob relieves</a>

[Oystein]

I just opened a Fireworks PNG file in Xara, and this happend - see graphics. When I opened he same file in Paint Shop Pro, the last version came up (not transparent)http://www.hesbynett.no/oystange/png.jpg .

[Sean Sedwards]

I usually find that PNGs are more compact than all but the simplest and smallest GIFs (buttons and bullets etc.). JPEG is still the best for photographic images, but PNG can give it a run for its money in mixed or complicated graphics, depending on the content and quality required.

The key advantages of PNG over GIF, from a user's point of view, are its greater colour depth, alpha transparency, gamma correction (not used much yet) and the flexibility to adapt to new requirements. From a programmers point if view, it's more complicated to implement than GIF but the compression technology is free, allowing anybody to write interpreters and creators. The LZW compression algorithm used in GIF is owned by Unisys and they charge $2000 up front plus a percentage for each download ... for freeware! Anybody that is offering free GIF viewers is probably doing so illegally or is very generous.

The flexibility of the PNG format allows Fireworks to add custom blocks of vector information and for the file format to remain valid for all other interpreters. Strictly speaking, this is contrary to the spirit of the PNG specification which discourages any one company from hijacking the format. The idea behind PNG is that it is universal and free for all web users and any permanent additions or changes will be for the benefit of all.

Regards - Sean