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We present a single-shot image processing method to reduce speckle noise mitigating undesired blurring effects in both amplitude and phase reconstructed images. The implementation is based on the average of multiple median filtered images with different kernel size. This approach provides final reconstructed amplitude and phase images with reduced speckle contrast and without penalizing the spatial resolution.
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Combined speckle- and propagation-based single shot two-dimensional phase retrieval method
Single-shot two-dimensional (2D) phase retrieval (PR) can recover the phase shift distribution within an object from a single 2D x-ray phase contrast image (XPCI). Two competing XPCI imaging modalities often used for single-shot 2D PR to recover material properties critical for predictive performance capabilities are: speckle-based (SP-XPCI) and propagation-based (PB-XPCI) XPCI imaging. However, PR from SP-XPCI and PB-XPCI images are, respectively, limited to reconstructing accurately slowly and rapidly varying features due to noise and differences in their contrast mechanisms. Herein, we consider a combined speckle- and propagation-based XPCI (SPB-XPCI) image by introducing a mask to generate a reference pattern and imaging in the near-to-holographic regime to induce intensity modulations in the image. We develop a single-shot 2D PR method for SPB-XPCI images of pure phase objects without imposing restrictions such as object support constraints. It is compared against PR methods inspired by those developed for SP-XPCI and PB-XPCI on simulated and experimental images of a thin glass shell before and during shockwave compression. Reconstructed phase maps show improvements in quantitative scores of root-mean-square error and structural similarity index measure using our proposed method.
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- PAR ID:
- 10559697
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 32
- Issue:
- 26
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 46939
- Size(s):
- Article No. 46939
- Sponsoring Org:
- National Science Foundation
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