RPi Macro Camera: An Inexpensive and Handheld Camera Based on the Raspberry Pi Computer for Plant Phenotype Studies

Abstract. The technological and scientific advancement in the field of agriculture has opened a new era for design and development of modern devices for plant phenotype studies. To take advantage of recent advances in mobile technology, we built a low-cost point-and-shoot prototype camera called RPi Macro Camera, RMC, using for photographing macro images of plant. RMC consists of a Raspberry Pi computer equipped with adjustable CMOS camera modules easily to removed and replaced, as well as a lithium battery, and a 5-inch touchscreen liquid crystal display. The package size of the RMC measured about 130 x 100 x 100 mm3 and it weighed less than 600 grams. The total cost of the components was less than USD 150. The inexpensive camera, RMC, was tested on serial sections of wheat straw in different growth stages dyed with safranin O-fast green supported over microslides. Our prototype camera was direct photography with samples in conventional environment with power supplied from battery. The camera was able to obtain good-quality images for statistical analysis on red and green intensity associated with simple programming including image segmentation and color calibration. With modest improvements and further image processing algorithm, RMC is expected to be useful for a variety of plant phenotype studies