Depth perception in single rgb camera system using lens aperture and object size: a geometrical approach for depth estimation

Abstract

In recent years, with increase in concern about public safety and security, human movements or action sequences are highly valued when dealing with suspicious and criminal activities. In order to estimate the position and orientation related to human movements, depth information is needed. This is obtained by fusing data obtained from multiple cameras at different viewpoints. In practice, whenever occlusion occurs in a surveillance environment, there may be a pixel-to-pixel correspondence between two images captured from two cameras and, as a result, depth information may not be accurate. Moreover use of more than one camera exclusively adds burden to the surveillance infrastructure. In this study, we present a mathematical model for acquiring object depth information using single camera by capturing the in focused portion of an object from a single image. When camera is in-focus, with the reference to camera lens center, for a fixed focal length for each aperture setting, the object distance is varied. For each aperture reading, for the corresponding distance, the object distance (or depth) is estimated by relating the three parameters namely lens aperture radius, object distance and object size in image plane. The results show that the distance computed from the relationship approximates actual with a standard error estimate of 2.39 to 2.54, when tested on Nikon and Cannon versions with an accuracy of 98.1% at 95% confidence level.

Effect of Lens Aperture for Analysis of Bubble Image Size Microbubble Generator Aeration System

“…Camera with highperformance imaging through a combination of micro camera and aperture image [40]. The camera focus is on the lens aperture setting [27,41]. The lens aperture speed of 1/125f at an airflow rate of 0.5 Lpm produces a maximum bubble of 77.5 μm, at 1.5 Lpm of 90.3 and 2.5 Lpm of 90 μm.…”

“…It is affected by the distance of the image object. According to Alphonse and Sriharsha [27], changes in aperture lens and object distance will affect the image results. Quantification of the effect output of the lens aperture increases the lens aperture lower can reduce image quality due to optical diffraction [44].…”

“…However, the use of high-speed cameras and lens aperture speeds still produce bubbles above standard. Alphonse and Sriharsha [27] use a camera to measure objects should pay attention to the object's distance, image field, and lens aperture.…”