So all of Photoshop buddies brag about how great the TinyPNG plugin is. I recently used their demo on the homepagee, and was amazed by how much it compressed my files. Anyway, I was wondering if you peeps know of an equivalent plugin for Gimp. I'd like to be able to automate the process on my website, Website Beaver, as it is a pain to have to manually do this for my designs.

Please let me know if there are any custom tools to help me out. I did a search, but couldn't find anything useful. Please don't recommend using the default png compression. Yes, .png is excellent for lossless compression, but I'm looking for a "pseudo-lossy" compression if that makes sense. I'm surprised that no one else has asked this before.

Your problem will be a 'universal' format so first sticking with png.

This is from the tinypng web page

and you can do that with Gimp manually or use the old Gimp save-for-web plugin
http://registry.gimp.org/node/33

save-for-web looks like this with some file sizes for comparison.
the original Lenna.png,
256 colour indexed png,
the number of colours reduced a little to 180.



Then of course there are much better new (and unpopular) formats such as better portable graphics (bpg) which beats indexed hands down for size and quality.
http://bellard.org/bpg/ and a gimp plugin that opens them. http://www.mikropunto.org/?p=71

And there is jpeg2000, gimp will open but not create. You could use something like XnView to make them.

I've actually never heard of .bpg, but just looked it up and it seems to be so much better than jpeg. I'm surprised why no browser supports it. I just followed your tutorial, which was excellent with the screenshots. While it did reduce the size my photos in png-8, there was something extra TinyPNG did to compress it much more. I think I read that they use something called pngquant to power their service.

I was going to mention XnConvert (by XnView).

In GIMP I always use save-for-web (Rich mentioned). The file size difference between PNG-24 & PNG-8 is impressive.
A few command line tools, optipng, advpng, pngcrush.

You can always try RIOT plugin too. Have had issues trying to get the new version to work with the GIMP though. The version that comes with Irfanview still works great fortunately.

http://luci.criosweb.ro/riot/

RIOT is good but be aware the installer contains Opencandy. Take care during the install.

I couldn't get it to work for GIMP like the older version. I now just depend on Irfanview when I actually need to use RIOT (RIOT comes with Irfanview when you install the plugins with it as well).

IMO indexed does not keep TRANSPARENCY, while png does, thus converting the image to indexed does not fullfilling the initial requirement

Yeah it's weird how the RIOT plug-in no longer works in GIMP. Just keeps loading the plug-in. Until it crashes with a message it cannot find the riot.dll file.

I downloaded the stand alone from here. Just unzip and double click the executable. Allow the installer to install into the 32 bit programs folder and it will give you options for further gimp plug-in directory searches for install.
http://luci.criosweb.ro/riot/thank-you- ... -installer

The stand alone works really well for me. I just downloaded the gimp plug-in version and installed everything then deleted the riot executable and dll file from the plug-ins folder.

Easy enough to open the image in RIOT through Rob A's glorious shellout filter i think.


Just make sure you re-name and save the new image on the desktop instead of the tmp folder.