1. A method for processing an image of a retail shelf area, the method being implemented by one or more processors and comprising: receiving an image of the retail shelf area, the image depicting the retail shelf area at an angled and depthwise perspective in relation to a point of image capture; determining a portion of the image that depicts one or more shelves in the retail shelf area in an angled alignment with respect to a predefined horizontal reference frame, to reflect the angled and depthwise perspective; based on the determination of the portion of the image depicting the one or more shelves, modifying the image to depict the one or more shelves as being parallel to the predefined horizontal reference frame; based on the modified image, detecting one or more products in a remainder portion of the image, separate from the portion of the image determined to depict the one or more shelves; determining a discrepancy of at least one product depicted in the remainder portion of the image with respect to a planogram of the retail shelf area; and generating an output that identifies the determined discrepancy.