Visual Field – Raspberry Pi Eye

17May 2017 by pi-eye-admin

Visual Field Construction – Heal Plot

Starting with this earlier post we have been discussing the construction of a stable visual field using techniques that use key-point matching and motion sensing. In both cases we attempt to map input from a three-dimensional scan onto an easily viewed two-dimensional surface. But any notion that we have a hi-def flat screen in our head or visual system is surely misguided. The world we live in is inherently a three dimensional space and we should be looking at how to properly represent a 3D world into a 3D data structure. Fortunately, this same problem came up in an earlier and completely different context. NASA launched satellites to study the cosmic microwave background (CMB) anisotropy (cosmic radiation in the universe) and needed software that met certain criteria for mapping radiation…

17May 2017 by pi-eye-admin

Visual Field Construction – Sensors

Open CV, Visual Field

In our previous post on visual field construction we discussed motion and how motion feed-forward may be used to create a stable visual field. Our body has such sensors in the head and their is no question that they play an important part in visual processing. From the Wikipedia article on the Inner Ear: "The vestibular system of the inner ear is responsible for the sensations of balance and motion. It uses the same kinds of fluids and detection cells (hair cells) as the cochlea uses, and sends information to the brain about the attitude, rotation, and linear motion of the head. The type of motion or attitude detected by a hair cell depends on its associated mechanical structures, such as the curved tube of a semicircular canal or the…

17May 2017 by pi-eye-admin

Visual Field Construction – Motion Feed Forward

Open CV, Visual Field

The first post in this series on visual field construction discussed eye motion and the problem of creating a stable visual field. A solution using photo-stitching was presented and shown to yield visually pleasing results. Stitching, however, is an after-the-fact remedy, a post-processing of visual input deriving results when the image in question might have already come and gone. This post proposes a second method of stabilization relying on "motion feed forward". When our brain decides to move our body a complex series of neuronal messages goes out to all parts, to the feet, the torso, the head and elsewhere to effect that move. It would make sense for the visual system to siphon off some of these commands and prep the visual field for an incoming adjustment, e.g. the…

17May 2017 by pi-eye-admin

Visual Field Construction – Stitching

Open CV, Visual Field

The study of visual perception has engaged philosophers and scientists for centuries if not millennia. And the problem is still not well understood, despite new results using machine learning and technologies such as convolutional deep neural networks. How photons impinging on the retina convert into visual perceptions in the mind has been the center of volumes and volumes of scholarly articles and debate. We won't solve this problem here, but I do wish to explore one area of this discussion which concerns eye movements and construction of the visual field. So much visual research starts with a simple static image (ImageNet now has over 14 million such classified images) and tries to derive a response from the image. The computer is presented with an image of a bowl of fruit…