Perception of detail and greyscale range in X-ray fluoroscopy images captured with a personal computer and frame-grabber

Grey scale texture analysis of endobronchial ultrasound mini probe images for prediction of benign or malignant aetiology

“…The 8‐bit greyscale images have numerical pixel values ranging from 0 (black) to 255 (white), which are used for greyscale texture analysis. The human eye can discern approximately 80 levels of grey …”

“…The human eye can discern approximately 80 levels of grey. 12 Tissue diagnosis via cytology of brushings or histology of biopsy samples or surgically resected lesions was taken as gold standard to define malignant or benign aetiology. In addition, benign aetiology was defined as stability or resolution of parenchymal changes on repeat CT scan at a greater than 12-month interval.…”

Optical Differentiation Between Malignant and Benign Lymphadenopathy by Grey Scale Texture Analysis of Endobronchial Ultrasound Convex Probe Images

“…The human eye can discern approximately 80 levels of gray. 18 Tissue diagnosis via cytology of TBNA samples or histology of surgically resected lymph nodes was taken as the gold standard to defi ne malignant or benign cause. In addition, benign cause was defi ned as stability or resolution of lymphadenopathy at a Ն 6-month repeat CT scan.…”

Grey value contrast sensitivity of dental practitioners in function of luminance and age

“…In the original experiment by Okkalides one of the squares of a four by four grid of squares was randomly selected and increased by one grey value level with respect to the 15 remaining squares. 12 In our test the increase in grey value levels was chosen between one and 50 to accommodate for the increased grey value depth of the present medical images and the increased display quality since Okkalides conducted his experiments (based on eight bit depth, allowing for 264 steps). In contrast to other studies the study by Okkalides explored all available background grey values and all 16 positions, clearly this can lead to fatigue of the observer.…”

“…Grey value perception has been explored in several studies. [12][13][14] In order to estimate the JND in a standardized way the experimental methodology described by Okkalides was modified to be used for a 12-bit grey value display. 12,15 Through this experiment patterns of grey level sensitivity are explored for several dental practitioners and the effect of age on eye sight.…”