1. A method comprising: receiving, by an image calibration system, data representative of an input camera image; detecting, by the image calibration system, a face of a person represented in the input camera image; determining, by the image calibration system, a predefined skin tone template that includes data indicating a tonal range and a tonal distribution for each of a plurality of skin tone regions of the face of the person, the tonal range and the tonal distribution collectively representing a preferred set of skin features of the person; modifying, by the image calibration system, the input camera image to change an appearance of the face of the person in the input camera image by changing the plurality of skin tone regions of the face of the person represented in the input camera image based on the data indicating the tonal range and the tonal distribution included in the predefined skin tone template; outputting, by the image calibration system, the modified camera image for display, the modified camera image comprising video content output in real time, the modified camera image being output for display as part of a mirror application running on a camera device; providing, by the mirror application, a user selectable option to toggle between the modified camera image and the input camera image; and overlaying, by the mirror application, a makeup guide template on the display of the modified camera image; wherein the makeup guide template provides a preferred makeup representation of at least one region of the face of the person in accordance with the predefined skin tone template, the makeup guide template providing a visual aid to guide the person in an actual application of makeup to the face of the person.