1. A method for automatically determining an emotional content of a digital image using a dimensional space model with valence and arousal coordinates, the method comprising: receiving, by a processing device, the digital image from the memory of a device used to capture or store the digital image; extracting, by the processing device, visual information from the digital image; extracting, by the processing device, shape features in the image to compute computational constructs of visual properties including roundness and angularity and compute the computational constructs; and computing, by the processing device, information relating to the emotional content of the digital image using a dimensional space model of emotions with valence and arousal coordinates based upon the extracted shape features, the extracted visual information, or computed computational constructs of visual properties; and providing, to an output device in communication with the processing device, the computed information relating to the emotional content of the image, wherein the output device provides the computed information to a user, wherein the extracted visual information includes color or texture of the digital image; wherein the extracted shape features comprise one or more of line segments, continuous lines, angles, or curves; wherein the roundness in the image is automatically computed by fitting the shape features extracted from the image to a circle characterized by how closely the extracted shape features of the image approaches that of a circle, and wherein the angularity in the image is automatically computed by: fitting the shape features extracted from the image to ellipses and measuring an elongatedness of the fitted ellipses, and characterized by maximum elongatedness of the fitted ellipses, or a statistical measure of a distribution of angles computed between extracted intersecting line segments, the statistical measure being one of the minimum value, the maximum value, a percentile, the difference between percentiles, the difference between the maximum and minimum values, the total number of angles, the median angle, the mean angle, or a standard deviation of angles.