Jung Jae-Hyun, Aloni Doron, Yitzhaky Yitzhak, Peli Eli
Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA.
Department of Electro-Optics Engineering, Ben-Gurion University of the Negev, Beer Sheva, Israel.
Vision Res. 2015 Jun;111(Pt B):182-96. doi: 10.1016/j.visres.2014.10.023. Epub 2014 Nov 3.
There are encouraging advances in prosthetic vision for the blind, including retinal and cortical implants, and other "sensory substitution devices" that use tactile or electrical stimulation. However, they all have low resolution, limited visual field, and can display only few gray levels (limited dynamic range), severely restricting their utility. To overcome these limitations, image processing or the imaging system could emphasize objects of interest and suppress the background clutter. We propose an active confocal imaging system based on light-field technology that will enable a blind user of any visual prosthesis to efficiently scan, focus on, and "see" only an object of interest while suppressing interference from background clutter. The system captures three-dimensional scene information using a light-field sensor and displays only an in-focused plane with objects in it. After capturing a confocal image, a de-cluttering process removes the clutter based on blur difference. In preliminary experiments we verified the positive impact of confocal-based background clutter removal on recognition of objects in low resolution and limited dynamic range simulated phosphene images. Using a custom-made multiple-camera system based on light-field imaging, we confirmed that the concept of a confocal de-cluttered image can be realized effectively.
针对盲人的假体视觉技术取得了令人鼓舞的进展，包括视网膜和皮层植入物，以及其他使用触觉或电刺激的“感官替代设备”。然而，它们都存在分辨率低、视野有限以及只能显示少数灰度级（动态范围有限）的问题，严重限制了它们的实用性。为了克服这些限制，图像处理或成像系统可以突出感兴趣的物体并抑制背景杂波。我们提出了一种基于光场技术的主动共焦成像系统，该系统将使任何视觉假体的盲人用户能够有效地扫描、聚焦并“看到”仅感兴趣的物体，同时抑制来自背景杂波的干扰。该系统使用光场传感器捕获三维场景信息，并仅显示其中包含物体的聚焦平面。在捕获共焦图像后，去杂波过程基于模糊差异去除杂波。在初步实验中，我们验证了基于共焦的背景杂波去除对低分辨率和有限动态范围模拟光幻视图像中物体识别的积极影响。使用基于光场成像的定制多相机系统，我们证实了共焦去杂波图像的概念可以有效地实现。
