Robust stereo infrared camera calibration for 3D depth estimation and measurement

With increased use of light-weight materials with low factors of safety, non-destructive testing becomes increasingly important. Thanks to the advancement of infrared camera technology, pulse thermography is a cost efficient way to detect subsurface defects non-destructively. However, currently available evaluation algorithms have either a high computational cost or show poor performance if any geometry other than the most simple kind is surveyed. We present an extension of the thermographic signal reconstruction technique which can automatically segment and image defects from sound areas, while also estimating the defect depth, all with low computational cost. We verified our algorithm using real world measurements and compare our results to standard active thermography algorithms with similar computational complexity. We found that our algorithm can detect defects more accurately, especially when more complex geometries are examined.

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Corners positioning for binocular ultra-wide angle long-wave infrared camera calibration

Optik ◽

10.1016/j.ijleo.2019.163441 ◽

2020 ◽

Vol 206 ◽

pp. 163441

Author(s):

Ziang Wang ◽

Bingqi Liu ◽

Fuyu Huang ◽

Yichao Chen ◽

Shuai Zhang ◽

...

Keyword(s):

Camera Calibration ◽

Infrared Camera ◽

Wide Angle ◽

Long Wave ◽

Long Wave Infrared

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Depth estimation and camera calibration of a focused plenoptic camera for visual odometry

ISPRS Journal of Photogrammetry and Remote Sensing ◽

10.1016/j.isprsjprs.2016.04.010 ◽

2016 ◽

Vol 118 ◽

pp. 83-100 ◽

Cited By ~ 25

Author(s):

Niclas Zeller ◽

Franz Quint ◽

Uwe Stilla

Keyword(s):

Camera Calibration ◽

Depth Estimation ◽

Visual Odometry ◽

Plenoptic Camera

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Near-Infrared Camera Calibration for Optical Surgical Navigation

Journal of Medical Systems ◽

10.1007/s10916-015-0427-8 ◽

2016 ◽

Vol 40 (3) ◽

Cited By ~ 3

Author(s):

Ken Cai ◽

Rongqian Yang ◽

Qinyong Lin ◽

Sujuan Liu ◽

Huazhou Chen ◽

...

Keyword(s):

Camera Calibration ◽

Near Infrared ◽

Surgical Navigation ◽

Infrared Camera ◽

Optical Surgical Navigation

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Calibration Method for Stereovision Measurement of High-Temperature Components Using Two Infrared Cameras

International Journal of Automation Technology ◽

10.20965/ijat.2013.p0163 ◽

2013 ◽

Vol 7 (2) ◽

pp. 163-170

Author(s):

Le Song ◽

◽

Zi-Hui Zhang

Keyword(s):

High Temperature ◽

Camera Calibration ◽

Infrared Imaging ◽

Signal To Noise Ratio ◽

Infrared Camera ◽

Calibration Method ◽

Detection Algorithm ◽

Low Contrast ◽

Vision Measurement ◽

High Temperature Components

The infrared vision measurement method has some advantages over visible vision in the measurement of high-temperature components. Infrared imaging is based on different imaging principles, however, making it unreasonable to adopt a conventional visiblelight camera calibration method directly. The present study proposes a dual infrared-camera calibration program in which we use the infrared imaging principle to measure high-temperature components threedimensionally. We use two ceramic balls as calibration targets against the background of an external hightemperature radiation source. Multiple feature points are generated from the precise movement of these targets. In order to improve the accuracy of the calibration method, we took the following approaches: A highly accurate edge-detection algorithm is realized by using a fuzzy neural network that is self-learning, self-adaptive, and utilizes fuzzy processing. We thus achieve a low signal-to-noise ratio and low contrast in infrared images. The distance between these two ceramic targets is used as a calibration reference to further reduce the temperature effect and to improve calibration accuracy and efficiency. The calibration results we got are an average residual error of 6.4134 µm and a variance of 2.9205 µm.

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