Tuesday, March 12, 2013

Linux Has Hundreds of New Filters!

G'Mic Mirror Array Effect

If you like playing around with Digital Photo Filters, have I got something for you! Although it's been around for awhile, it has just had a major upgrade, adding hundreds of new filter effects. It's called G'mic, which is short for "Grey-C's Magic for Image Computing". Strange name I know, but appropriate, as it can take you into a wonderfully strange world with your images. It is developed under the Opensource license (Linux), which means it can be had for free, and is in fact, normally installed as a single plug-in for GIMP, which you should know by now, is fully platformed for Linux, Windows and Mac Operating Systems. I have frequently mentioned GIMP as an Opensource alternative for Photoshop, and now, with the full extended package of GIMP and G'MIC combined, it's even more compelling.

GIMP is capable of doing most of the things you've learned to do in Photoshop, breaking your images down into Layers and Channels, along with hundreds of special effects. G'MIC just added hundreds more, to truly bring out the artist in you. Now since I've declared that I am not a Photographer, but rather an "Enthusiast for Photographs, not Photography", I dare to say that I like my photographs to look like photographs, and not something else, and herein lies my contempt for the High Dynamic Range technique, as the end result, unless applied with great subtlety, does not come out looking like a photograph. However, I've found in GIMP and G'MIC some fun and creative ways to play around with your digital photos, and still retain your integrity as a photographer, instead of blowing your integrity all to hell using HDR. This is a short little demo of some things I like about G'MIC's latest toys.

First, a source image:

Out My Front Door, Canon T3i with Industar 50-2 Lens

I've frequently shot this scene, as it's one that I can do with sock-feet. All I need to do is open my front door and shoot across the street. It's nothing more than a straight from camera JPEG test shot, so let's see what G'MIC can do with it, shall we? The picture at the top is done with a filter called "Array > Mirrored". Here's another one which might be the most important of all, although it's value is not apparent when viewed on a screen - this is for photographers who do B&W printing:

Psuedo Gray Black and White

A discussion on the importance of this is found here. Psuedo Gray is a means of converting a colour image to black and white which actually makes use of digital colour values that are "almost grey". Normally, a Black and White Conversion makes use of 256 values of Luminance. A Psuedo Gray conversion is able to add thousands more values, as needed, to make a much smoother tone transition within the picture. It is difficult to see any difference on a computer screen, but it should make a terrific difference when doing B&W prints. I should also mention that the current version of GIMP is only 8-bit, and to get more than 256 values, a 16-bit platform is required. The really good news is that the 16-bit GIMP will be coming very soon, and this will really open up a new world for B&W printing using Opensource software.

Now, let's get away from the technical stuff and have some good old "filter fun":

Tiled Normalization on the Saturation Channel


Old Photo

I'm sticking to the extremely conservative here, because like I said, I like my photographs to look like photographs. But G'MIC offers plenty of really wild stuff, if you're so inclined.






I could go on, but why not see for yourself? GIMP is very easy to install, and the newest version 2.8.4 comes with G'MIC and all it's latest enhancements. To verify that all is well, open a picture in GIMP, then go to Filters > G'MIC... > then you should see a large list of categories, starting with "Arrays and Frames, Artistic, Black and White, Colors" .... etc. I should also mention that each individual effect has it's own Slider box that opens in a separate pane which allows endless degrees and modifications to each effect.

G'MIC is like Instagram on mega-steroids!


  1. Thanks Dave, I've shared this blog entry on the G'MIC Google+ page : https://plus.google.com/u/0/b/117441237982283011318/117441237982283011318/posts

  2. Not Just Linux it runs under windows and MAC too.

  3. Yeah I know - I always like drawing attention to Linux as much as possible. Thanks!


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