Motion sensing method of sub-pixel level precision

A method for sensing motion of an object with respect to a surface, comprising the steps of:

• step 1, acquiring a first frame of image, and setting the first frame of image as a reference frame;
• step 2, delaying a specific time and acquiring a second frame of image, and setting the second frame of image as a sample frame;
• step 3, subjecting the reference frame and the sample frame to interpolation respectively to obtain an interpolated reference frame and an interpolated sample frame;
• step 4, calculating correlation between the reference frame and the sample frame to obtain an initial motion vector;
• step 5, calculating correlation between the interpolated reference frame and the interpolated sample frame to obtain an interpolation motion vector;
• step 6, correcting and compensating the initial motion vector according to the interpolation motion vector and an interpolation parameter to obtain a first output motion vector;
• step 7, dividing the first motion vector by the interpolation parameter to obtain a second motion vector and send the second motion vector to a computer;
• and
• step 8, updating the reference frame or leaving the reference frame unchanged according to the first motion vector and a predetermined value.