Images have been transformed into pixels and projected onto
a headset to help the visually impaired in everyday tasks such as navigation,
route-planning and object finding.
Developed using a video camera and mathematical algorithm,
the researchers from the University of Southern California hope the pixels can
provide more information and enhance the vision of patients already fitted with
Lead author of the paper, James Weiland, said: "Blind
people with retinal implants can detect motion and large objects and have
improved orientation when walking. In most cases, they can also read large
"At the moment, retinal implants are still
low-resolution. We believe that our algorithm will enhance retinal implants by
providing the user with more information when they are looking for a specific
How the study was
A total of 19 healthy subjects were involved in the study,
who each undertook training first to get used to the pixelated vision. During
the study, they were fitted with a Head Mounted Display (HMD) and took part in
three different experiments: walking an obstacle course; finding objects on an
otherwise empty table; and searching for a particular target in a cluttered
A video camera was mounted onto the HMD which collected
real-world information in the view of the subject. Mathematical algorithms
converted the real-world images into pixels, which were then displayed onto the
HMD's screen in front of the subject
The algorithms used intensity, saturation and edge-information
from the camera's images to pick out the five most important, or salient,
locations in the image. Blinking dots at the side of the display provided the
subjects with additional directional cues if needed.
All three of the experiments were performed with and without
cues. When subjects used the directional cues, their head movements, the time
to complete the task and the number of errors were all significantly reduced.
The subjects learnt to adapt to pixelated vision in all of
the tasks, suggesting that image processing algorithms can be used to provide
greater confidence to patients when performing tasks, especially in a new
It is possible that the device could be fitted with voice
description so that the subjects are provided with cues such as "the red
target is to the left".
"We are currently looking to take this a step further
with object recognition, so instead of telling subjects that 'the red object is
to the left', it will tell them that 'the soda can you want is to the left',"