The Orientation filter is useful for finding vertical or horizontal images.
The horizontal image is an image where horizontal resolution is significantly greater than vertical resolution (Landscape mode):
A vertical image is an image captured what is commonly known as Portrait mode:
In order to determine the orientation of the image, the ImageRanger uses the Aspect ratio formula and compares the result with predefined values.
If the width and height resolution parameters of the image are close to each other (within a fixed tolerance of 20%), the image is considered Square: