Television images of ginned cotton sample surfaces are being digitized and captured in computers for trash content analysis. This technique is being incorporated into trashmeters which are being developed to automate particle counting and area measurement for use in cotton marketing. Area measurement accuracy is controlled by the accuracy of locating the edge of each particle in the recorded image. Since less than 5% of each frame is represented by trash. Particle edges are defined by the percent or amount of reflectance change from the background lint. This method is accurate for white cottons with small quantities of trash. However, its accuracy is reduced for off-color cottons and for samples containing lightly Colored trash particles. Video scan measurements are reported for several simulated reference samples (dots on panels) used in developing improved thresholding calibration methods.