Quantitative spot extraction of fluorescent antibodies from a fluorescence microscopy image. (a) Original image. Fluorescence micrograph of caveolin-1 molecules stained with the primary antibody and a secondary fluorescent antibody in normal fibroblasts. Scale bar: 10 μm. (b) The results of spot extraction using the proposed method. These spots were superimposed on the original image as red regions. (c) The histogram of the intensity as estimated from the extracted spots.