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Title: Extracting flat-field images from scene-based image sequences using phase correlation

Abstract

Flat-field image processing is an essential step in producing high-quality and radiometrically calibrated images. Flat-fielding corrects for variations in the gain of focal plane array electronics and unequal illumination from the system optics. Typically, a flat-field image is captured by imaging a radiometrically uniform surface. The flat-field image is normalized and removed from the images. There are circumstances, such as with remote sensing, where a flat-field image cannot be acquired in this manner. For these cases, we developed a phase-correlation method that allows the extraction of an effective flat-field image from a sequence of scene-based displaced images. The method uses sub-pixel phase correlation image registration to align the sequence to estimate the static scene. The scene is removed from sequence producing a sequence of misaligned flat-field images. An average flat-field image is derived from the realigned flat-field sequence.

Authors:
 [1];  [2];  [3]
  1. Research Support Instruments, 4325-B Forbes Boulevard, Lanham, Maryland 20706 (United States)
  2. Naval Research Laboratory, Code 7231, 4555 Overlook Avenue, SW, Washington, DC 20375 (United States)
  3. Naval Research Laboratory, Code 8231, 4555 Overlook Avenue, SW, Washington, DC 20375 (United States)
Publication Date:
OSTI Identifier:
22597912
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 87; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CAPTURE; CORRELATIONS; EXTRACTION; GAIN; ILLUMINANCE; IMAGE PROCESSING; IMAGES; OPTICS; REMOTE SENSING; SURFACES; VARIATIONS

Citation Formats

Caron, James N., E-mail: Caron@RSImd.com, Montes, Marcos J., and Obermark, Jerome L. Extracting flat-field images from scene-based image sequences using phase correlation. United States: N. p., 2016. Web. doi:10.1063/1.4954730.
Caron, James N., E-mail: Caron@RSImd.com, Montes, Marcos J., & Obermark, Jerome L. Extracting flat-field images from scene-based image sequences using phase correlation. United States. doi:10.1063/1.4954730.
Caron, James N., E-mail: Caron@RSImd.com, Montes, Marcos J., and Obermark, Jerome L. 2016. "Extracting flat-field images from scene-based image sequences using phase correlation". United States. doi:10.1063/1.4954730.
@article{osti_22597912,
title = {Extracting flat-field images from scene-based image sequences using phase correlation},
author = {Caron, James N., E-mail: Caron@RSImd.com and Montes, Marcos J. and Obermark, Jerome L.},
abstractNote = {Flat-field image processing is an essential step in producing high-quality and radiometrically calibrated images. Flat-fielding corrects for variations in the gain of focal plane array electronics and unequal illumination from the system optics. Typically, a flat-field image is captured by imaging a radiometrically uniform surface. The flat-field image is normalized and removed from the images. There are circumstances, such as with remote sensing, where a flat-field image cannot be acquired in this manner. For these cases, we developed a phase-correlation method that allows the extraction of an effective flat-field image from a sequence of scene-based displaced images. The method uses sub-pixel phase correlation image registration to align the sequence to estimate the static scene. The scene is removed from sequence producing a sequence of misaligned flat-field images. An average flat-field image is derived from the realigned flat-field sequence.},
doi = {10.1063/1.4954730},
journal = {Review of Scientific Instruments},
number = 6,
volume = 87,
place = {United States},
year = 2016,
month = 6
}
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