Corners

You can easily add corners to your image at Image Magick in a few simple steps.

First I took this image to Image Magick Studio.

Click on Transform. In the box enter the parameters for half of the width and half of the height, preceded by plus signs. This image is 200x200, so I entered +100+100. Click roll and transform.

Next click on Draw. Under Primitive, choose circle. In the parameter box enter 100,100,70,70 (center of image and width -30, height -30 pixels for width and height, even if image is not square), enter fill and stroke color (I used green) click draw. Click on Draw again and enter 100,100,80,80, (20 pixels smaller), red for the color and click draw.

Go back to transform and roll again at the same parameters as before. The result is below.

You can draw a rectangle instead. I used 70,70,130,130 for the parameters for the green, and then made 2 more squares 10 pixels smaller for the white and red.

You can also roll and composite an image over the center and roll back to get the corners. The image should be symmetrical. Here I used this snowflake.

which produced this image.

Here I drew a red circle with green stroke color at 100,100,70,70, then drew a white square with green stroke color at70,70,130,130.