multi-view 3d video acquisition using hybrid cameras with beam splitter

8/3/2019 Multi-View 3d Video Acquisition Using Hybrid Cameras With Beam Splitter

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BY

JASEEM ROSHAN.B

ROLL NO 22

MULTI-VIEW 3D VIDEO ACQUISITION USING

HYBRID CAMERAS WITH BEAM SPLITTER

1 College of engineering chengannur



CONTENTS

College of engineering chengannur2

y What is 3D?

y Multi-view 3D video acquisition system

y Camera system setup

y Multi view video system setupy Captured video processing

y Conclusion

y References



What is 3D?


y 3D means three-dimensional , i.e. something that has width,

height and depth (length). Our physical environment is three-

dimensional and we move around in 3D every day.

y

Humans are able to perceive the spatial relationship betweenobjects just by looking at them because we have 3D perception,

also known as depth perception.



Multi-view 3D video acquisition system


Depth acquisition

Passive approach Active approach

Image-based

disparity estimation

Time-of-flight (TOF)

camera



Multi-view 3D video acquisition system




Camera System Setup


y The proposed hybrid camera system consists of three-color

cameras and one time of flight (TOF) camera.

y A beam splitter is used between the color camera of the

center view and the TOF camera to minimize the FOVdifference between two cameras.

y Capture three-view color and one-view depth videos



Camera System Setup




Multi-view Video Capture System Setup


y Use two capture servers with RAID HDD system, a

synchronization signal generator, and video capturing software

y With a software, its able to capture three-view color videos and

one-view depth videos with hardware synchronization

y There are three kinds of images that can be captured from the TOF

camera.

1. A depth image that is quantized gray image with 256 levels

2. An intensity image that represents a gray level image of the

scene.

3. An amplitude image that reflects the signal strength of the

active illumination.



Captured Video Processing


y In order to obtain better quality of depth for multi-view 3D

video.We first calibrate each camera in order to estimating

extrinsic and intrinsic parameters

y

For camera calibration MATLAB toolbox is used



Color Video Processing


y Color correction

y It analyze the differences between corresponding patches,

and calculate the correction curve using non-linear

regression.





Captured color chart for color correction





Example of rectified multi-view images



Depth Calibration


y The depth values in the depth video from the TOF depth

camera are very sensitive to noises.

y Compute the depth of the planar checker pattern within the

limited space by increasing the distance from the checkerpattern to the depth camera using our system



Depth Image Filtering


y For the removal of salt noise.

y Salt noise is unusually very large compared to the depth

values of correct neighboring depth pixels.

y

These unexpected depth pixels should be removed and besubstituted by new depth values.

y Averaging filter together with median filter is used



Depth Image Filtering


(a) Original (b) After filtering



3D Warping of Depth


y Its then generate the initial depth images for high-resolution

multi-view images by performing 3D warping of the depth

values to the obtained from the TOF depth camera.

y

Project pixels of the depth images into the 3D worldcoordinate using the obtained depth values

(a) Color image (b) 3D warped depth



Stereo Matching with Warped Initial

Depth


y Utilize the warped depth values as initial depth values for the

stereo matching.

y Thus can overcome the mismatching problem in the texture

less regionsy To reduce mismatched depth values along object boundaries,

detect moving objects using color difference between frames.



Advantages


y It has a limited bandwidth increase compared to 2D so that it

can be used in existing distribution infrastructures.

y Offers flexibility and compatibility with existing production

equipment and compression tools.



Disadvantages


y It is not compatible with existing 2D or 3D-Ready displays.

y 2d-plus-Depth cannot handle transparency.



REFERENCES


y MULTI-VIEW 3D VIDEO ACQUISITION USING HYBRID

CAMERAS WITH BEAM SPLITTER

Gi-Mun Um1, Taeone Kim1,Gun Bang1, Namho Hur1, Eun-Kyung

Lee,Jae-Il Jung,Yun-Suk Kang,G yo-Yoon Lee, and Yo-Sung Ho.

y J. Zhu, L.Wang, R. Yang, and J. Davis, ́ Fusion of Timeof- Flight

Depth and Stereo for High Accuracy Depth Maps,µ P roc. IEEE

Conference on Computer Vision and P attern Recognition (CV P R) 2008, pp.

1-8, June 2008.

y 3D Interface Specifications White Paper Philips 3D Solutions

multi-view 3d video acquisition using hybrid cameras with beam splitter

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