▲ Triangle

Triangle is a tool to create image arts using the delaunay triangulation technique. It takes an image as input and it converts to abstract image composed of tiles of triangles.

The technique

• First the image is blured out to smothen the sharp pixel edges. The more blured an image is the more diffused the generated output will be.
• Second the resulted image is converted to grayscale mode.
• Then a sobel filter operator is applied on the grayscaled image to obtain the image edges. An optional threshold value is applied to filter out the representative pixels of the resulting image.
• Lastly we apply the delaunay algorithm on the pixels obtained from the previous step.

blur = tri.Stackblur(img, uint32(width), uint32(height), uint32(*blurRadius))
gray = tri.Grayscale(blur)
sobel = tri.SobelFilter(gray, float64(*sobelThreshold))
points = tri.GetEdgePoints(sobel, *pointsThreshold, *maxPoints)

triangles = delaunay.Init(width, height).Insert(points).GetTriangles()

Installation and usage

$ go get github.com/esimov/triangle/cmd/triangle
$ go install

Supported commands

$ triangle --help

The following flags are supported:

Flag	Default	Description
in	n/a	Input file
out	n/a	Output file
blur	4	Blur radius
max	2500	Maximum number of points
noise	0	Noise factor
points	20	Points threshold
sobel	10	Sobel filter threshold
solid	false	Solid line color
wireframe	0	Wireframe mode (without,with,both)
width	1	Wireframe line width
gray	false	Convert to grayscale

Setting a lower points value, the resulted image will be more like a cubic painting. You can even add a noise factor, giving a more artistic, despeckle like result for the final image.

In case the gray filter is set as true the resulting triangulated image will be converted to grayscale mode.

Here are some examples you can experiment with:

$ triangle -in samples/clown_4.jpg -out output.png -wireframe=0 -max=3500 -width=2 -blur=2
$ triangle -in samples/clown_4.jpg -out output.png -wireframe=2 -max=5500 -width=1 -blur=10

Below are some of the generated images:

License

This project is under the MIT License. See the LICENSE file for the full license text.