Image enhancement of real-time television to benefit the visually impaired.
OBJECTIVE
To examine the use of real-time, generic edge detection, image processing techniques to enhance the television viewing of the visually impaired.


METHODS
Prospective, clinical experimental study.


METHODS
One hundred and two sequential visually impaired (average age 73.8 +/- 14.8 years; 59% female) in a single center optimized a dynamic television image with respect to edge detection filter (Prewitt, Sobel, or the two combined), color (red, green, blue, or white), and intensity (one to 15 times) of the overlaid edges. They then rated the original television footage compared with a black-and-white image displaying the edges detected and the original television image with the detected edges overlaid in the chosen color and at the intensity selected. Footage of news, an advertisement, and the end of program credits were subjectively assessed in a random order.


RESULTS
A Prewitt filter was preferred (44%) compared with the Sobel filter (27%) or a combination of the two (28%). Green and white were equally popular for displaying the detected edges (32%), with blue (22%) and red (14%) less so. The average preferred edge intensity was 3.5 +/- 1.7 times. The image-enhanced television was significantly preferred to the original (P < .001), which in turn was preferred to viewing the detected edges alone (P < .001) for each of the footage clips. Preference was not dependent on the condition causing visual impairment. Seventy percent were definitely willing to buy a set-top box that could achieve these effects for a reasonable price.


CONCLUSIONS
Simple generic edge detection image enhancement options can be performed on television in real-time and significantly enhance the viewing of the visually impaired.
Wolffsohn
James S
JS
Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham, United Kingdom. j.s.w.wolffsohn@aston.ac.uk
Mukhopadhyay
Ditipriya
D
Rubinstein
Martin
M
D000368:Aged; D003199:Computer Systems; D015350:Contrast Sensitivity; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008297:Male; D011446:Prospective Studies; D013690:Television; D014786:Vision Disorders / Q000534:rehabilitation*; D015348:Vision, Binocular; D014792:Visual Acuity; D019987:Persons with Visual Disabilities / Q000534:rehabilitation*