Methods and apparatuses for calculating building heights from mono imagery

A computing system comprising:

• at least one processor;
• and
• at least one memory storing instructions that, when executed by the processor, cause the computing system to perform a process comprising:
• receiving, from a camera, an image of terrain with one or more structures;
• orthorectifying the image to remove effects of terrain distortion from the image;
• identifying edges of the one or more structures in the image, wherein the edges provide a rooftop vector on the one or more structures;
• identifying a footprint vector of the one or more structures in the image;
• calculating a structure height of the one or more structures based on a camera angle, a distance from the camera to the one or more structures, and a pixel offset from the footprint vector to the rooftop vector;
• creating a shadow mask for the one or more structures using the footprint vector as a reference;
• measuring a shadow structure height of the one or more structures based on the camera angle, the distance from the camera to the one or more structures, and a sun angle;
• and
• comparing the shadow structure height to the calculated structure height from the pixel offset from the footprint vector to the rooftop vector.

An apparatus comprising:

• a memory;
• one or more processors electronically coupled to the memory and configured for:
• receiving, from a camera, an image of terrain with one or more structures;
• orthorectifying the image to remove effects of terrain distortion from the image;
• identifying edges of the one or more structures in the image, wherein the edges provide a rooftop vector on the one or more structures;
• identifying a footprint vector of the one or more structures in the image;
• calculating a structure height of the one or more structures based on a camera angle, a distance from the camera to the one or more structures, and a pixel offset from the footprint vector to the rooftop vector;
• creating a shadow mask for the one or more structures using the footprint vector as a reference;
• measuring a shadow structure height of the one or more structures based on the camera angle, the distance from the camera to the one or more structures, and a sun angle;
• and
• comparing the shadow structure height to the calculated structure height from the pixel offset from the footprint vector to the rooftop vector.