Superimposing Dynamic Range

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Superimposing Dynamic Range is a process for increasing the contrast for digital and print media . This makes it possible to present high dynamic range content on low dynamic range displays or media.

General

A normal expression such as For example, a photo in natural light has a contrast ratio of around 100: 1. For the human eye this means around 130 perceptible gray levels . With digital monitors, especially with high-quality, medical monitors , a contrast of up to 400: 1 can be displayed, which corresponds to 200 perceptible gray levels. With this process, developed by the Bauhaus University Weimar , a contrast of up to 45,000: 1 (620 perceptible gray levels) can be achieved. Peak values ​​of up to 2750 cd / m² are therefore possible. The process is based on high dynamic range rendering. A camera automatically scans an image and registers it. A projector tailored to this camera throws this image back with a current accuracy of 0.33 mm. As a result, the color spaces and brightnesses are projected in such a way that, together with the color pigments of the printout, they achieve a contrast that equals or even exceeds that of X-ray films . The project, under the direction of Oliver Bimber , serves the cost-efficient and above all simple contrast intensification of paper printouts such as B. books, photos and radiological images. The use of electronic paper, the so-called e-paper , enables interactive purposes. The process has been patented since April 2008 and is being developed further together with Osaka University .

Use in radiology

Various media are used for documentation in radiology. One of them is the printout on paper, usually via DICOM print. These printouts are given to the patient or the respective referring physician, but they are used purely for documentation and not for diagnosis. The previous contrast ratio of these is limited due to the printing peripherals. With the help of SDR, a contrast is possible that is up to six times higher than that of a conventional X-ray film and provides a quality that is possible to diagnose.

Further possible areas of application

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