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Scanner noise was small: Â☐.3% SD for the Epson and Â☐.2% for the Vidar. Overall, the Epson scanner showed a 10% smaller range of pixel value compared to the Vidar scanner. Film‐to‐film variations for corresponding doses were measured to be within Â☐.4% SD for both Epson scanner and Vidar scanners. For repeated scans of a single film, the measurements in each dose region were reproducible to within Â☐.3% standard deviation (SD) with both scanners. ImageJ and RIT software was used for analyzing the Epson and Vidar scans, respectively. Scanners were tested using films irradiated with eight separate 3Ã-3 cm2 fields to doses ranging from 0.115–5.119 Gy. Measurements were made of scan orientation effects, response uniformity, and scanner noise.

We evaluated the Epson Perfection V700 Photo flatbed scanner and the Vidar VXR Dosimetry Pro Advantage scanner as measurement devices for radiochromic EBT film. The purpose of this study was to quantify the performance and assess the utility of two different types of scanners for radiochromic EBT film dosimetry: a commercial flatbed document scanner and a widely used radiographic film scanner. However, since the analyzed methods are not able to determine the image origin in all cases, further investigations are necessary.Įvaluation of a commercial flatbed document scanner and radiographic film scanner for radiochromic EBT film dosimetry One can conclude from the results achieved so far that identifying flatbed scanners is possible. In additional tests, we simulated the influence of flatfielding and down scaling as examples for such particularities of flatbed scanners on digital camera identification. This was confirmed by extensive tests: Identification was possible to a certain degree, but less reliable than digital camera identification. However, there are particularities of flatbed scanners which we expect to influence the identification. As characterization of flatbed scanner noise, we considered array reference patterns and sensor line reference patterns. Since flatbed scanners and digital cameras use similar technologies, the utilization of image sensor noise for identifying the origin of scanned images seems to be possible. A current method for the identification of digital cameras takes advantage of image sensor noise, strictly speaking, the spatial noise. Within this article, we investigate possibilities for identifying the origin of images acquired with flatbed scanners.