Image Processing

The fundamental goal of microarray image processing is to measure the intensity of the arrayed spots and quantify their expression values based on these intensities. In a complete approach, it will also assess the reliability of the quantified spots. Before these operations can be performed, the spots in the images must be identified.

The application uses a deformable grid scheme to locate any set of microarray data spots in the image. The grid’s spatial position is then used to segment out each individual spot. Then the spot signals intensity is determined along with their background levels to give a quantitative account of gene expression levels at every spot location on the image.

The above image illustrates some problems that might occur when quantifying gene expression image data. The blue circle indicates the valid signal and the small black ellipses mark contamination in both the signal and its background. Various image processing algorithms ensure that this and other types of contamination are removed from signal and background calculations.