In a computer this involves shifting right the bits and performing a logical operation on the sign bit. This is very inexpensive, as is assigning every bit to 0, in order to make the pointer null. It's easily extensible to m-valued arrays. In these types of arrays, each node's color is the average of the children's color. Whereas the CTC and the LQT do not support these representations, all we have to do for the autumnal quadtree is add an extra field for the color of each node.
Pointers are expensive from the storage viewpoint.
In the best case, each pointer requires two bytes of space and a color field requires one byte. The use of the autumnal quadtree is restricted to partial image manipulation. One would like to have one data structure to manipulate images. However, it seems that recently, space is at a lower premium than speed. Practical Introduction to Data Structures and Algorithm Analysis. .