* the direction of the last pixel in the first column from the
* first pixel in that column.
* Anatomical direction is designated by the capital
* letters: A (anterior), P (posterior), R (right),L (left),
* H (head), F (foot).
* the direction of the last pixel in the first column from the
* first pixel in that column.
* Anatomical direction is designated by the capital
* letters: A (anterior), P (posterior), R (right),L (left),
* H (head), F (foot).