In order to obtain the field flowmeter data that can not be transmitted as electrical signals automatically, the binarization is necessary. The current method can not eliminate the influence of the uneven illumination in processing the flowmeter data. Therefore, an improved weighted average algorithm combined with a rectangular box is put forward. The method of the summed-area table is used to calculate the sum of the gray values in each rectangular area of the flowmeter image, which reduces the running time effectively. Meanwhile, the method of the class space combined with the cohesion is applied to automatically adjust the parameters. With the C++ programming and the method, the image processing time is 1.6 ms. For the same image, the image processing time by the Wavelet Packet and the Niblack Method is 9.3 ms. Therefore, the image processing speed is significantly improved by the method. The experiments show that the binarization of the unevenly illuminated image is improved with the method and a better image is obtained from the flowmeter data. Hence, the accuracy of the flowmeter is improved.

uneven illumination image  /  adaptive weighted mean algorithm  /  two value processing