An imaging sensor’s spatial quality can be expressed by the system’s point spread function (PSF). The PSF of a pushbroom Charge-Coupled Device (CCD) satellite sensor was numerically modeled including contributions from optic, detector, sensor motion, and electronic components. Synthetic edge and pulse targets with various intensity levels were developed and then convolved with the generic senso...

In most typical digital cameras, even high-end digital single lens reflex ones (dslr), the acquired images are sampled at rates below the Nyquist critical rate, causing aliasing effects. In this work we describe a new algorithm for the estimation of the point spread function (psf) of a digital camera from aliased photographs, that achieves subpixel accuracy. The procedure is based on taking two...

Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear receptor that plays a major regulatory role in metabolic function. It is overexpressed in many types of cancer cells, suggesting that regulation of PPARγ may also affect carcinogenesis. Our previous study suggested that PTB-associated splicing factor (PSF) is a PPARγ-interacting protein and growth regulator of colon cancer ce...

With the development of computational photography, single-lens camera combined with corresponding image deblurring algorithm is gradually becoming a new research direction, replacing complex modern optical imaging system such as single lens reflex (SLR) camera. For camera, Point Spread Function (PSF) estimation accuracy will directly affect restoration effect. In this paper, we designed simple-...

Institute of Biophysics and Biomedical Engineering, Faculty of Sciences, University of Lisbon, Lisbon, Portugal Hybrid MR-PET scans enable acquisition of both types of images within a session. Despite consistent subject positioning, image alignment can still be challenging. Functional MR images rely on echo-planar imaging (EPI) and present geometric distortions due to static B0 field inhomogene...

The nonuniformity of the spatial response to surface radiation is a fundamental characteristic of all airborne and spaceborne sensors that inevitably introduces uncertainty into the estimation of object proportions by the spectral unmixing of mixed pixels. Simulated data of the surface radiation distribution and a TM (thematic mapper) response matrix were developed and utilized to imitate the g...

ABSTRACT The point spread function (PSF) reflects states of a telescope and plays an important role in the development data-processing methods, such as PSF-based astrometry, photometry, image restoration. However, for wide field small aperture telescopes (WFSATs), estimating PSF any position whole view is hard, because aberrations induced by optical system are quite complex signal-to-noise rati...

We perform an analysis of the TRACE telescope blur from EUV images. The blur pattern is discussed in terms of the telescope point spread function (PSF) for the 171 Å filter. The analysis performed consists of two steps. First an initial shape for the PSF core is determined directly from TRACE EUV images. Second, the blind deconvolution approach is used for obtaining the final PSF shape. The PSF...

Developing therapeutic approaches are necessary for treating hormone-refractory prostate cancer. Activation of androgen receptor (AR) and its variants' expression along with the downstream signals are mostly important for disease progression. However, the mechanism for marked increases of AR signals and its expression is still unclear. Here, we revealed that various spliceosome genes are aberra...

All lenses have optical aberrations which reduce image sharpness. These aberrations can be reduced by deconvolving an image using the lens point spread function (PSF). However, fully measuring a PSF is laborious and prohibitive. Alternatively, one can simulate the PSF if the lens model is known. However, due to manufacturing tolerances lenses differ subtly from their models, so often a simulate...