Region-of-interest processing for electronic visual prostheses

SPV studies suggest that one benefit of image processing may be to provide an importance mapping that can aid scene understanding by enhancing certain image features or regions of interest at the expense of discarding less important or distracting information.

“SPV studies suggest that one benefit of image processing may be to provide an importance mapping that can aid scene understanding; that is, to enhance certain image features or regions of interest, at the expense of discarding less important or distracting information (Boyle et al., 2008; Al-Atabany et al., 2010; Horne et al., 2016; Sanchez-Garcia et al., 2019).”

The first saliency extraction approach encountered in the review proposes constructing saliency maps by aggregating various visual features (distance, contrast, object size).

“The first saliency extraction approach encountered in our review proposes constructing saliency maps by aggregating various visual features (distance, contrast, object size).72”

The authors proposed an adaptive design by applying weights on each feature depending on the scene context.

“The authors proposed an adaptive design by applying weights on each feature depending on the scene context.”

The validation of phosphene maps was performed in normally sighted individuals, who were presented with saliency-enhanced phosphene maps computed from the original images.

“The validation of phosphene maps was performed in normally sighted individuals, who were presented with saliency-enhanced phosphene maps computed from the original images.”

The quality of the saliency maps was evaluated by asking participants to assess their preference for the advanced or a more basic approach, with phosphenes modelled as simple image pixels.

“The quality of the saliency maps was evaluated by asking the participants to assess their preference for the advanced or a more basic approach, with phosphenes being modelled as simple image pixels.”

The realism of simulated prosthetic vision models is frequently limited by an overall neglect of phosphene models, which are often confused with electrical stimulation protocols, or by using unrealistic simulation settings.

“However, the realism of these models is frequently limited by an overall neglect of phosphene models, which are often confused with electrical stimulation protocols,72 or by using unrealistic simulation settings.76,88”