The influence of the microscope lamp filament colour temperature on the process of digital images of histological slides acquisition standardization

Abstract

BackgroundThe aim of this study is to compare the digital images of the tissue biopsy captured with optical microscope using bright field technique under various light conditions. The range of colour's variation in immunohistochemically stained with 3,3'-Diaminobenzidine and Haematoxylin tissue samples is immense and coming from various sources. One of them is inadequate setting of camera's white balance to microscope's light colour temperature. Although this type of error can be easily handled during the stage of image acquisition, it can be eliminated with use of colour adjustment algorithms. The examination of the dependence of colour variation from microscope's light temperature and settings of the camera is done as an introductory research to the process of automatic colour standardization.MethodsSix fields of view with empty space among the tissue samples have been selected for analysis. Each field of view has been acquired 225 times with various microscope light temperature and camera white balance settings. The fourteen randomly chosen images have been corrected and compared, with the reference image, by the following methods: Mean Square Error, Structural SIMilarity and visual assessment of viewer.ResultsFor two types of backgrounds and two types of objects, the statistical image descriptors: range, median, mean and its standard deviation of chromaticity on a and b channels from CIELab colour space, and luminance L, and local colour variability for objects' specific area have been calculated. The results have been averaged for 6 images acquired in the same light conditions and camera settings for each sample.ConclusionsThe analysis of the results leads to the following conclusions: (1) the images collected with white balance setting adjusted to light colour temperature clusters in certain area of chromatic space, (2) the process of white balance correction for images collected with white balance camera settings not matched to the light temperature moves image descriptors into proper chromatic space but simultaneously the value of luminance changes. So the process of the image unification in a sense of colour fidelity can be solved in separate introductory stage before the automatic image analysis.

PATMA: parser of archival tissue microarray

“…Relocation of punches often happens during many steps of the TMA slide formation (Korzynska et al, 2014; Yaziji & Barry, 2006). It is impossible to predict if the punches will form askew line or will be randomly relocated.…”

Peer Review #1 of "PATMA: parser of archival tissue microarray (v0.1)"

“…One of the major problem we encountered are heavily skewed rows of TMA. Relocation of punches often happens during many steps of the TMA slide formation [35,36]. It is impossible to predict if the punches will form askew line or will be randomly relocated.…”

Survey: interpolation methods for whole slide image processing

“…Zooming and scaling are not to be confused (Sellaro et al ., ), because zooming does not need image resampling. That is why the role of image interpolation is so vital while evaluating whole slide images (WSI) (Korzynska et al ., ; Slodkowska et al ., ; Neuman et al ., ) of histological (Bueno et al ., ; Korzynska et al ., ; Lopez et al ., ) and cytological (Markiewicz et al ., ; Rojo et al ., ; Callau et al ., ) samples. Since those are images enormous in size, it is often necessary to lower their resolution or rescale them.…”