Estimation of coal particle size distribution by image segmentation ...
Two hundred images of coal piles comprised of coal sized above 3 mm were captured. Over 100 kg of coal were sampled and sieved manually into five size fractions: 36, 613, 1325, 2550, and 50100 mm. The size of the image was 1024 × 768 pixels and the imaged area was 18 × cm.