Wednesday, January 23, 2013

Walk Cycle in GIMP

It is almost Chinese New Year. I had an idea for animating a character. The one that came to mind was the one for person. It even looks like a man. What would I need to make it move though? I drew the 2 strokes first. But that is still a static interpretation.
The Paths Tool in GIMP was something I had not tried yet. It lets me draw the path and paint the strokes. In time, I almost matched the shape of the strokes I made from scratch.
This gave me a skeleton to work with. It was a something that could be manipulated as desired.
Use the Stroke Path dialog box to choose a brush type to paint the strokes. I chose Ink. Make sure beforehand the brush size is what you want.
Add a new layer and change the shape of the path. Deform it. And then I created the radical symbol for person.
Lastly, after repeating the steps to deform the strokes, the walk cycle is complete.

Wednesday, January 16, 2013


It's that moment when you realize you didn't have to use a diffuser to take these photos. I have been taking advantage of the acrylic surface and the six-sided nature of the aquarium. The light bounces off this material differently than on glass tanks. The flash usually reflects on the front of the surface. That's why I have to aim it on the trim or some other object directly in line of sight. In these, digital zoom, as shown in the upper right, and the two lower ones, keeps the flash point out of range. I always rhought it was the water surface that was absorbing the reflected light. Now I see that the back of the aquarium has a lot of bounce back too.

Saturday, January 5, 2013

Recreating a Stamp - Color to Alpha in GIMP

I want to go through a process of how I got...
from here...
to there.
It all started when I read an article of how to create a watermark in GIMP. For that, I used the text editor and created variations of @xindilini. I hadn't even figured out how to save the resultant paintbrush at the time. Then I remembered my chop. It is a customized stamp with my Chinese name carved in stone. The one I had in mind was the one that would produce a negative image of the characters.

I took a picture of the imprint with a webcam and started playing with the image in GIMP. After loading the image file, I created a new layer of the specific area so I could rotate it arbitrarily. Autocrop Layer. Autocrop Image.

Tried a few options from the Colors > Auto and settled for Stretch HSV. This would stretch the image contrast to cover the maximum possible range.
Now we are ready to use Color to Alpha. You can select this from the Layer > Transparency menu or directly from the Colors menu. Both will do the same thing. Other than the red inky parts are transparent because the default colour is white. If you want to change it you can click on the rectangle as shown in the following image.
I put it through one more pass to get the red to pop out some more. That is the by using Maximum RGB from the Colors menu. This will reduce the image to pure red, green, and blue. For this purpose, make sure the option "Hold the maximal channels" is selected.
You can now save the layer for later use. I took it one step further by combining it with calligraphy of my name. Since I am a bit out of practice, I traced it out by hand. Converting the image mode from RGB to Greyscale, I could use it for a watermark on dark or light images alike.
I really liked playing around with Color to Alpha. Can't wait to try it with other stamps or cutouts.