What is disclosed is a system and method for processing a video acquired using a 2D monocular video camera system to assess respiratory function of a subject of interest. In various embodiments hereof, respiration-related video signals are obtained from a temporal sequence of 3D surface maps that have been reconstructed based on an amount of distortion detected in a pattern placed over the subject's thoracic region (chest area) during video acquisition relative to known spatial characteristics of an undistorted reference pattern. Volume data and frequency information are obtained from the processed video signals to estimate chest volume and respiration rate. Other respiratory function estimations of the subject in the video can also be derived. The obtained estimations are communicated to a medical professional for assessment. The teachings hereof find their uses in settings where it is desirable to assess patient respiratory function in a non-contact, remote sensing environment.