N on linear calibration and finding circle edge were introduced to measure the images acquired.

系统选用背光源照明，采用非线性校准及查找圆边的方法对采集到的图像进行测量。

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Spatial calibration and finding circle center are introduced to measure the images acquired from different angles, and the results are perfect.

采用空间校正及查找圆边的方法对同一零件旋转不同角度采集到的图像进行测量，从而得到被测参数的精确结果。

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By image calibration, median filtering and fast pattern matching processing algorithms, the system acquires the position information of the coordinates of the center of the circle of eccentric sprue.

经图像标定、中值滤波、快速图像匹配等处理算法，获得偏心加注口的圆心坐标位置信息。

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Before you can get started, though, you need to do a one-time calibration process, which involves following a circle moving around the screen.

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There's some calibration involved when moving from person to person, chasing a circle around the screen with your eyes.

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