U.S. flag An official website of the United States government
  1. Home
  2. Medical Devices
  3. Science and Research | Medical Devices
  4. Method for Assessing Texture Reproduction of Camera-phone-based Medical Devices
  1. Science and Research | Medical Devices

Method for Assessing Texture Reproduction of Camera-phone-based Medical Devices

Catalog of Regulatory Science Tools to Help Assess New Medical Devices

Technical Description

This tool is a method that enables users and manufacturers to perform rapid and robust texture reproduction assessment of camera-phone-based medical devices (CPMDs). The assessment method needs a test target below. The exact design of the target might vary. The target has a central texture region (also called the DL region) that consists of a series of overlapping low-contrast discs. The discs have varying radii and uniformly distributed gray levels; giving an accurate stochastic occlusion model that mimics a natural scene. Images of the target will be captures by a CPMD and then averaged to remove noise. The averaged image will then be evaluated for texture loss compared with the target.

Camera-phone-based medical devices represent a major emerging platform for point-of-care diagnostic imaging of biological tissue. However, camera phones lack complex lens systems and large sensors used on digital single-lens-reflex cameras in order to minimize final system weight and manufacturing cost, while still achieving satisfactory performance for consumers. Hardware shortcomings are often compensated with extensive image modifications performed by an image signal processor. Consequently, images captured by a CPMD commonly contain residual noise and artifacts introduced in the image processing steps, which might cause texture loss and thus affect CPMD effectiveness.

Example of an image captured by a CPMD

Intended Purpose

The tool can be used to compare the amount of tissue texture details lost in images captured by a subject CPMD and predicate CPMD, thus enables, streamlines, or otherwise improves CPMD development.

While the tool was original designed for texture reproduction assessment of CPMDs. It can be extended to any optical imaging medical devices that do not have severe geometric distortion. The tool will be mainly used by an engineer who understand principles of signal processing.


Described in peer-reviewed publication:


The tool cannot be used for CPMDs with severe geometric distortion since such distortion will change the frequency-domain information in the dead-leaves target.

Supporting Documentation

Relevant publication:


Tool Reference

In addition to citing relevant publications please reference the use of this tool using DOI: 10.5281/zenodo.8229876

For more information:

Back to Top