Well TIFF has very poor compression leading to large file sizes compared even to PNG. And thus no one uses it on the web.

FLIF has very good compression, it will only download the minimum amount of data required to display the image at it's current resolution. It supports 32-Bit images/animations/transparency. It does animation playback in realtime while it's downloading the file. So as it plays the resolution just increases, you aren't waiting for the next frame to load, only improve. FLIF can also handle the incredibly high resolution images that TIFF is usually used for, and can even do tiled rendering, where it only loads the chunks of the image you are zoomed in at into memory at that resolution. Meaning it takes less time to render those chunks on gigantic images and it uses less memory to do so.

FLIF is an incredibly powerful format that offers a lot. It has archival, scientific, and web purposes. It likely won't be useful to those in 3D or Gaming as files like TGA are better suited for faster reading/loading where as FLIF is a little slower to decompress than PNG. But then again, game devs have been optimizing resource usage for a long time giving models that are further away lower poly counts and lower quality bitmaps/textures. So having one flif image to work at any distant may be of use for them, where they truncate the file at different lengths depending on distance from the camera.

There is a lot to be explored with this format, and it isn't even finalized yet.

TIFF can do tiled images too and there is nothing stopping someone from adding a TIFF extension for better compression or anything else imaginable.

TIFF compression is rubbish. If you just want a lossless image, PNG is everywhere now. The main (possibly only?) reason to use FLIF over PNG is the better compression.

Because isn't open source, and is a proprietary format from Adobe ?

While not Open Source TIFF has age advantages in that close to anything related to it is unencumbered by patents, or will soon cease to be if any do remain. Also TIFF is an open container like MKV and can be used for far more than just simple pictures.

>Also TIFF is an open container like MKV and can be used for far more than just simple pictures.

I see this commonly in different business and medical applications where information may need to be accessible for years or decades after creation. There is a pretty even mix of TIFF and PDF/A in these environments and because of the legal liabilities I don't see them being displaced.

Not to mention TIFF supports layers. From a skim of the homepage, this doesn't.

FLIF allows for animation, and it is very possible to interpret each frame of the animation as it's own layer. This would year the same lossless quality as a TIFF at a much smaller file size. Though FLIF isn't intended to be used for this purpose, neither was PNG, and that didn't stop Fireworks from abusing that format and adding layering. The same could be done by someone who wants to add a little meta data to the file to let layered flif opening applications know that the frame are to be interpreted in that manner.

This format isn't complete yet, if layering is important to you, you should join the gitter.im/FLIF-hub/FLIF chat room.

A bigger question here is why not build FLIF as a document format using an established container? Why not use something established, mainstream and non controversial like TIFF as the container and FLIF as the codec. I'm kind of sick of this "new file format and file extension for no good reason" crap. MKV as a container and I dont care about codec because FFMPEG/VLC/etc support all the codecs is great, it hides all the complexity and enables codec experimentation without hassle. FLIF is an image encoding/decoding scheme that would be completely compatible inside a TIFF image if implemented correctly.

Why do I care about having a "dot flif" file when the new codec is the important improvement?

Is '*.flif' actually a good thing?

Personally I don't think so, mainly because without a mechanism to drive adoption in browsers, the format offers very little value to anyone over existing formats. TIFF would be a decent solution to that problem. ... And the fact that FireFox has marked TIFF support as WONTFIX is actually pretty indicative of how unlikely they are to support a new format such as FLIF. Sad but true. From what I already see of the FireFox support thread for FLIF, its not going to happen any time soon.