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Sensor noise informed representation of hyperspectral data, with benefits for image storage and processing
1Norwegian Defence Research Establishment (FFI), Kjeller, Norway. torbjorn.skauli@ffi.no
Optics Express
|July 13, 2011
Summary
This study introduces two new hyperspectral data representations to incorporate sensor noise into image processing. These methods, corrected raw data and variance-stabilized data, improve noise estimation and data compression for better analysis.
Area of Science:
- Remote Sensing
- Image Processing
- Sensor Physics
Background:
- Hyperspectral image processing often overlooks sensor noise information, despite its importance.
- Current radiance data representations can lead to suboptimal results in spectral analysis and compression ratio calculations.
Purpose of the Study:
- To define alternative hyperspectral data representations that make sensor noise accessible for image processing.
- To enable more accurate noise estimation, data compression, and algorithm reformulation.
Main Methods:
- Defined a "corrected raw data" representation, proportional to photoelectron count.
- Developed a variance-stabilized representation using a square-root transformation of the photodetector signal.
Main Results:
- Corrected raw data allows simpler noise estimation and more compact storage.
- Variance-stabilized data achieves signal-independent noise, reduces data volume by nearly half, and offers a better measure of uncompressed data size.
- Both representations facilitate the incorporation of sensor noise into hyperspectral processing algorithms.
Conclusions:
- Alternative data representations are crucial for leveraging sensor noise in hyperspectral imaging.
- These new representations can lead to more robust and efficient hyperspectral data analysis and processing.
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