Sound of Vision â 3D scene reconstruction from stereo vision in an ... Implemented in Python using. Csound ... Processing of the disparity map. Removal of ...
Sound of Vision – 3D scene reconstruction from stereo vision in an electronic travel aid for the visually impaired
M. Owczarek, P. Skulimowski, P. Strumillo Date: 14.7.2016
Sound of Vision project EU Horizon 2020 - prototype wearable electronic travel aid • Aim of the project: a wearable ETA for assisting blind persons by rendering the image of the environment through an auditory display • The prototype device captures a 3D image of the environment, processes it in realtime, and presents the relevant information to a blind user • New approaches to 3D scene reconstruction and segmentation
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Stereovision -> Disparity map
xL
d = |XL-XR| Page: 3
xR
UV-disparity representation of disparity map
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Proposed methods for 3D scene reconstruction • Direct sonification of the “U-disparity” • The concept of the simplified sound icons Stereovision camera
Disparity
Estimation of ground plane
(on CPU)
(based on disparity and depth maps)
Depth
Obstacle detection
“U-disparity”
(after ground plane and background removal)
(representation of the scene)
Obstacle blobs
“Obstacle map”
(image moments, mask, etc.)
(s cene segmented into ground and obstacles)
Point cloud (of extracted obstacles)
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Basic UV-disparity sonification What was done: Simple U-disparity image sonification Implemented in Python using Csound Moog Ladder synthesizer Pentatonic scale, 6-9th octave. Stereo panning Nonlinear distance scaling
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The concept of the simplified sound icons Raw disparity map
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Processing of the disparity map Removal of background, ground plane and all elements >2m above it
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The concept of the simplified sound icons Minimum-area bounding rotated rectangles outlining the detected obstacles
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The concept of the simplified sound icons Result segmentation map
Current and future work • Merging stereovision data with Structure Sensor data (for improved indor vision) • Detection and sonification of special object categories: • Walls • Stairs • Holes/dropoffs • Hanging face/torso level obstacles • Doors • Text • Persons
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Summary
• A simple and effective method of detecting obstacles and the ground plane has been developed • Obstacles can be detected even if the quality of the disparity map is low • Assumption: the ground plane occupies significant part of the image and is clearly visible • Weakness: only significantly large obstacles can be detected due to narrow base of the stereovision system
http://icchp2016.naviton.pl/
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Acknowledgment
This work received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 643636 ”Sound of Vision”.