I am currently working on a computer vision project that involves analyzing video data of a person captured from a webcam. In this project, I need to compute the depth map or distance of a specific object (in my case, the nose of the person) from the camera. Unfortunately, I do not have access to any reference image with known depth or distance information for calibration purposes.
Considering the constraints of working with webcam-captured video data and the absence of reference images, are there any known or solved algorithms/methods that can help me achieve accurate depth estimation? I would greatly appreciate any insights, resources, or techniques that can be employed to estimate the depth or distance of the person from the webcam without the need for a reference image. Thank you for your assistance!