Friday, 30 September 2016

I've seen the future and it will be.

Im planning to start a new blog. A lot of considerations have to be made and im heavily experimenting at the moment,
trying new techniques.
Here is something i came up with yesterday.



Thursday, 8 September 2016

Parallel Things

Stranger Things with a hint of Suicide Squad, when really im a Mr Robot guy.
All the way.

Currently doing research for a tutorial. Stay tuned !


Saturday, 2 July 2016

Manual Posterization


In todays tutorial im gonna show you how to posterize an image manually.
This technique has several usages that you can apply to a lot of projects.

One application is for making stencils. It gives you more control than using Contrast or Quantizing your image.

Another application is using the posterized image as a base that you can trace in Inkscape and then modify with node editing.

You can also use it to apply textures, like hatchings, to an image or create a pop art effect.


As with most projects, the image you use is crucial. Look for a sharp image that has good contrast and lighting, and not too small.
Desaturate it and if needed, add some Contrast or Brightness.

Im using an image of Marilyn Monroe from pixabay.com.
Its 1359x1920px.


1. Remove the background with any technique you like. I made a mask in Inkscape, because the Path (Bezier) Tool is very easy to use, so all i had to do is export the mask-image in the correct pixelsize and open it as a layer in Gimp.

You can download my mask here.

If you use a selection to render your image, just invert the selection and fill with white. Deselect, invert the image so that you get a negative and jump to step 3.

Also make sure you save that selection to a channel for future use !


You can use as many colors as you like for your posterization, but between two and five seems like a good value. The famous 'Obama Hope' poster by Shepard Fairey has five colors (actually four plus one additional tone that is achieved by mixing two colours).


2. Im going with five colors.

Preparing the mask

a) Add a layermask to your image.


b) Copy the mask layer and paste it into the layermask. A floating selection will appear. Anchor that layer, by clicking the little anchor symbol.


We want the background to be white, so i put a new white layer under the original image.


c) merge your original image with the layermask down, then invert the image (Colours → Invert).
This image will be our mask.



3. 
Set up the tone layers


To set up the layers, copy the final mask-layer image to the clipboard, and create a new (in my case, yellow) layer.
Add a layermask with a right-click and with the layermask selected, paste and anchor the copied mask-image.



In case you dont fully understand layermasks, here is a good short summary i picked up from Glyn Dewis youtubechannel:

"Black conceals and White reveals."

So a layermask acts like a filter, showing all the colour (in this case yellow) where there is white on the layermask, and blocking all the yellow where there is black on the mask. Shades of grey gives you transparent yellow.




4. Duplicate that layer as many times as you want colors, minus two.
Your first, lightest color, doesnt need a layermask and the background needs a different layermask.



5. Add a layermask to the darkest colour layer and copy/paste the mask you used to render your image, but invert it (click on layermask, then 'Colors → Invert').



6. Finally add all the inbetween colours, by drag and dropping them to your layers (or use the Bucket Tool).
Darkest colours on top, lightest to the bottom.


Here are the colours i used:



7.
Threshold the layers

Now its time for the creative fun part.
By manipulating the values of the layermask, we can control what the mask reveals or conceals.

Select the layermask and call up the Threshold Tool.
Move the slider to the right, until you have the amount of shadows you want. In my case im focusing on the eyes.



8. Repeat this for all the other tone-layers, from top to bottom (you can see the values i used in the layernames of the screenshot).

If you are unhappy with a particular layer of your finished result, you can re-paste the original mask and try again.

You can use this method to colorize an image and give it a pop-art effect.


In case you find this confusing or difficult, i uploaded an xcf file with the basic setup (color layers with layermask), you can use to just try out the thresholding step.
The original file is 12,3MB in size so i compressed it. Use a program like 7zip or Winrar to unzip.





Simplifying

If you want to simplifiy and clean up the thresholded mask you can blur it before you apply the thresholding.
In this example i used a value of 3px for the shadows to preserve detail and a value of 8px for the lighter shades.



Composite

What you can also do is make two images with the same colours but different levels of simplification and later composite them with a layermask.

For this image i used a version of the posterized image, where every layermask had a Blur of 20px applied before thresholding.


I used the strongly blurred mask version as the base and combined it with the detail of the eyes and lips of this tutorial's image by painting with a brush on the layermask.

open in new tab for bigger version

Using hatchings

Of course you can also use textures instead of colours. For a hatching effect i used a rotated grid.

That concludes this tutorial, hope you like it !


Monday, 9 May 2016

All you need is love

Reaction to a very busy forum.


https://youtu.be/QbCUJG68p-A

Filtered Triangles Background

In todays tutorial, im gonna show you how to make a cool triangle wallpaper type background, with Inkscape and Gimp.



1. Open Inkscape and set up your canvas under File → Document Properties.
Im going with a canvas of 800x800px.
Make sure 'Border on top of drawing' is ticked.

2. Call up the Star Tool and change the number of corners to 3.


3. With the Ctrl key pressed, draw a triangle. That way the tip will be perfectly straight.
My triangle has a height of 60px.

4. Align the triangle with the 'Align & Distribute Dialogue', so that the right tip is lined up with the left side of the canvas and at the same height with the top.


5. Convert the triangle into a path (CTRL + Shift + C). Because we used the star and not the polygon, our triangle has 6 nodes. This is important when we later edit the shape to get rid of rendering gaps.

6. Next call up the Tiled Clones Dialogue (Edit → Clone → Create Tiled Clones) and set the Rows and Columns so that the width and height is covered with clones.
In my example thats 14.
Also make sure the Shift X per Row is set to 50%, as in the screenshot.


7. Delete the clone that is on top of our original triangle.

Now select all the triangles outside the right side of the canvas with a rubberband selection and make sure your snapping has 'snap to cusp nodes' enabled.
Move the selected objects to the left side and make your pattern into a full square with the help of snapping.


8. Next select all your triangles, duplicate, unlink the clones to convert into paths (Shift + Alt + D) and change the color to something different (i used red).
Group them for a moment, flip horizontically and ungroup again.
This should fill in the triangular gaps.


9. Almost finished with the Inkscape part.
If we leave our triangles the way they are now, we would get rendering gaps after the export. Like this:


There is a simple fix, courtesy of Lazur URH, thanks to the power of clones.
What we want is an overlap so that there are no gaps between objects.
Select any of your yellow triangles and if its a clone (check the Status bar), press Shift + D.
That will select the original path.
With the Node Tool, move each node that divides the lines of the triangle in half, a bit outwards.
All clones will follow and all the gaps will be closed.


EDIT: an alternative, perhaps even easier method: just perform an outset to your triangle. Simple and elegant solution !

10. To finalize the pattern, select all triangles, unlink the remaining clones and give everything the same colour.
Go to Extensions → Color → Randomize…
Depending on the settings, you will get results like this:

 

11. Finally export your image, save the project and close Inkscape.



Its time for the filtering in Gimp !



12. Open your image in Gimp, and call up G'MIC.
Set the 'Output Mode' to 'New Layer', and the 'Output Message' to 'Verbose (layer name)'.
That way your original image will stay the same and you can always reproduce the results, because G'MIC displays all the value settings in the layername.


Try filters like Dream Smoothing, Colored Pencils, Graphic Novel or Graphic Boost and get results like this:

Colored Pencils
Dream Smoothing
Graphic Boost
Graphic Novel
Vintage Style
Cartesian Transform Desaturated and Colorized