Fig. 4From: Computer vision-based wood identification and its expansion and contribution potentials in wood science: A reviewGrayscale image expressed in a matrix of numbers that computers can process. a 8-bit grayscale stereogram of a cross section of Cinnamomum camphora. b Enlarged image of the yellow box in a, which contains a vessel. c Gray values of each pixel in b. Scale bar = 1 mmBack to article page