Project Proposal:

Determining depth based on Time of Flight Principle




Neeraj Kumar

October 15, 2007


1. Introduction


Range imaging is a critical part of computer vision. Many different technologies are used to determine the range image including structured light, laser scanners and Shuttered Light Pulse. Among all these technologies, Shuttered Light Pulse can provide high resolution range images at video frame rates which makes it interesting.


SLP is based on the fact that the speed of light is finite. Light from an object, closer to the imager, returns before the light from an object farther away. SLP recovers the depth by emitting and shuttering a short pulse of light.


2. Overview of the system

The experiments will be carried out on a Z-mini camera. The Z-mini provides a real-time Color and Depth information (RGBD) video stream. The depth data is available for all objects within the Field Of View (FOV) and within the maximum range selected by the operator and segmentation of a scene using just one camera. The range and resolution of the depth data is controllable by the user.

The control & communication unit of the camera sends out a signal to the fast gating & timing unit to start flooding the scene with pulses of infrared light. The fast gating & timing unit shapes characteristics of the pulses such as pulse duration, the number of photons per pulse and signal rise/drop-off time.

The pulses get contoured and reflected by the objects in the scene. The depth sensor then measures the accumulation of photons to determine the exact distance of each pixel in the scene. The signal then travels to the control & communication unit, which performs the calculations essential for object tracking, interpolations and noise reduction.


Pulsed light and Reflected light


3. Experiments

The initial set of experiments will be to collecting image data using the Zmini camera. The next set of task is yet to be decided.



4. References


3. Manual for the Z-mini camera


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