Measurement of fish eggs with a image processor

A new method of measuring fish eggs is introduced. By utilizing an image processor, both the number and the diameters of fish eggs can be recorded rapidly and simultaneously. The image processing system employed is composed of TV cameras, display monitors, a computer and a printer. The measurement procedure is summarized as follws: 1. Separation and cleaning of fish ova by an ultrasonic vibrator. 2. Image processings and measurement of fish eggs by means of the image processor. 3. Statistical calculation and print-out of the results. Samples, taken from ovaries of Japanese common mackerel, have different stages of maturity and contain known numbers of eggs. Countings are made ten times for each sample. The numbers recorded are all a little less than the actual numbers. The mean errors, however, do not exceed 2%, and a considerably high accuracy of measurement was realized. Also this method was 5 to 8 times more efficient than the microscopic one. The result suggests that the device is useful for the measurement of fish eggs and could be applied to measurements in fishery science which investigate the various characteristics of object images