Free Lossless Image Format Publications • Hacker News Board

Re: Free Lossless Image Format Publications

#41

Post by jonsneyers » Tue, Oct 04, 2016, 1:10 PM UTC

faragon wrote: post #37

jonsneyers wrote: post #36

Earlier quoted context omitted.

Here are some results for a few black & white images from https://commons.wikimedia.org/wiki/Category:PD-ScottForesman : (I only compare to JBIG2, not Group 4, since JBIG2 is supposed to be the best of those two) JBIG2 FLIF PNG 11690 10903 27093 1971_San_Jose_Scale_Scales_on_Branch 10458 9761 23466 1971_San_Jose_Scale_Winged_Adult 44809 44301 105555 Accommodation_ladder 15966 14882 44073 Aconite 27031 25877 59353 Add…

Thank you! It looks amazing. So unless processing speed or memory requirements being a handicap, the FLIF could be a real generic graphics compression candidate :-)

Yes, that's the goal :)

Re: Free Lossless Image Format Publications

#42

Post by jonsneyers » Tue, Oct 04, 2016, 1:12 PM UTC

jonsneyers wrote: post #35

mark-r wrote: post #16

Earlier quoted context omitted.

Thanks, I missed that. Still it means that e.g. Photoshop will never support it, leading to the same conclusion.

I'm open to negotiation if Adobe would want to include the FLIF encoder in Photoshop. The other contributors have signed a CLA that allows me to change the licensing to anything more permissive than GPLv3. So if Adobe wants it, they can pay for a non-copyleft license (e.g. Apache 2.0). If that ever happens, I'll be happy to share the licensing fees with the other contributors and donate some of it to the FSF.

Also, Adobe Photoshop (or any other program) is of course free to dynamically link to the libflif library. The LGPL allows that.

Re: Free Lossless Image Format Publications

#43

Post by jandrese » Tue, Oct 04, 2016, 2:02 PM UTC

jaredcheeda wrote: post #28

jandrese wrote: post #20

Earlier quoted context omitted.

So it's lossy if you truncate the file? How does it compare to JPEG on a quality/size basis?

The truncated version is basically a lower resolution. So if you have a 5000x5000px image and you display it on your page as 100x100px, it only needs to download a small amount of data to show it at that lower resolution. Obviously being a lower resolution it won't match pixel-for-pixel identically to the original, but if you downloaded the whole file it would. FLIF does support a "lossy" encoding method too. The com…

Is it possible to tell the encoder to do that pixel twiddling or do you have to do it by hand still?

Re: Free Lossless Image Format Publications

#44

Post by jonsneyers » Tue, Oct 04, 2016, 5:57 PM UTC

jandrese wrote: post #43

jaredcheeda wrote: post #28

Earlier quoted context omitted.

The truncated version is basically a lower resolution. So if you have a 5000x5000px image and you display it on your page as 100x100px, it only needs to download a small amount of data to show it at that lower resolution. Obviously being a lower resolution it won't match pixel-for-pixel identically to the original, but if you downloaded the whole file it would. FLIF does support a "lossy" encoding method too. The com…

Is it possible to tell the encoder to do that pixel twiddling or do you have to do it by hand still?

The encoder option -Q (that's a capital Q, lowercase -q is used to decode a lower quality preview by only reading part of the file) can be used to do lossy encoding, where -Q100 is lossless and -Q0 is usually the most lossy you would want to go. But you can go lower if you want, using a negative number (e.g. -Q-50); there is not really any lower bound.

Re: Free Lossless Image Format Publications

#45

Post by h1d » Wed, Oct 05, 2016, 4:07 AM UTC

jonsneyers wrote: post #35

mark-r wrote: post #16

Earlier quoted context omitted.

Thanks, I missed that. Still it means that e.g. Photoshop will never support it, leading to the same conclusion.

I'm open to negotiation if Adobe would want to include the FLIF encoder in Photoshop. The other contributors have signed a CLA that allows me to change the licensing to anything more permissive than GPLv3. So if Adobe wants it, they can pay for a non-copyleft license (e.g. Apache 2.0). If that ever happens, I'll be happy to share the licensing fees with the other contributors and donate some of it to the FSF.

Why would they want to pay? Unless the format is widely spread and the fee is much cheaper than implementing their own what interest do they have to pay? I feel it's the opposite now.