Sorry if this is old news but WebP looks quite promising, haven’t had the time to fully check it but it looks promising.https://developers.google.com/speed/webp/docs/webp_lossless_alpha_study#results
Oh shiznitz, it appears to be 26% smaller than PNG in lossless formats and 25-34% smaller in lossy 
Interesting though surprised if its so good that we’ve not heard of it before or much since?
Its open-source, but a very quick browse didn’t reveal any actual license, so I don’t know if the license makes it unappealing to be integrated say into Unity. Certainly with such improvements in levels of compression and the fact it offers both lossless and lossy in a single format is appealing.
It’s not a new format. It’s about two years old actually.
Anyway, rather few people use it. I’ve seen maybe just two websites using webp images.
AFAIK the license isn’t the problem, but the lack of advertising on the product is. Can’t figure out why though.
Several things: 1) yes WebP is several years old, and 2) it’s not immediately applicable to realtime graphics. E.g. in Unity the game does not use PNG or JPG at runtime; the textures are stored in a GPU-friendly format instead (unless you’re “downloading pictures from the internet”).
Can you provide insight as to why it hasn’t over taken the PNG format, in web sites and other multimedia formats?
Chicken meets egg with Facebook, Chrome WebP support | Ars Technica pretty explanatory.
Ah, I see. Thanks everyone. Gonna mess around WebP a bit.
Yeah but the point is that as developers we could see a potential saving of 25% or more across all source images used for textures, which along with audio and video are the biggest files in any project.
Of course the problem is, as pointed out above, the uptake of the format appears low, so whilst you can get plugins for say Photoshop, Adobe haven’t (from a quick search) supported it be default. Then there is a question of how OS’s display thumbnails of these files, I assume the format needs support somewhere in the OS for this. All of this would make daily use of the format awkward and there would always be the worry that support would drop off, then you’ll left with assets in an incompatible format.
Still it might be nice if Unity could give developers the option of switching by adding support for importing for WebP. With the above savings I could see it being very useful for those working as groups via internet or cloud based systems to reduce overall bandwidth usage.
Regarding the question of why WebP hasn’t taken over PNG, if you look you’ll also find that JPEG2000 hasn’t taken over JPEG… yet it is a superior format and has been around for apparently at least 10 years. Some browsers are starting to support it.
What I think is, as networks and computers have gotten faster people use the throw more speed at it solution at it and don’t bother about efficiency or optimization as much as they used to. Harddrive are huge compared to what they were, CPU’s are hugely faster, there’s tonnes more ram, and networks are relatively super quick… it kind of undoes the underlying NEED for greater compression. In the past, the need to compress was born out of severe hardware limitations. To usurp the existing commonplace formats, any new format is going to have to be significantly better plus have widespread support.
Over the years Ive heard of JPEG2000 and figured it had just bee rolled into jpeg format 
Well WebP certainly fulfils the first criteria, up to 25% better compression on lossless is huge and up to 30% for lossy is pretty good too. However yeah support seems to be slow or none existent. I guess it would really take a big player like Adobe to integrate it as a native plugin to all their products before it has a chance of catching on.
Though I agree in terms of hardware we often have memory to spare, there are still benefits to reducing project sizes (specifically the source assets) as it means for larger projects they can be moved around quicker (e.g. transfer over network or onto usb stick), but perhaps more importantly over the internet. Sure broadband speeds are increasing all the time, but here in the UK at least download is normally many times faster than upload. So much so that 25-30% savings on the source textures used in a Unity project could definitely have a large impact on the time it takes to transfer those projects between non-local team members.
I’m guessing its not possible for a developer to write a WebP plugin for Unity, I don’t just mean a script to import the data, but for the plugin to seamless be integrated with Unity’s importers.