Abstract: Based on the global motion of the scene caused by the movement of the camera focus, a method named MOF(Motion Of Focus) was established. As the camera moved freely, the compensation of the overall movement was needed for the strong parallax caused by the depth of field. From the perspective of the camera, analysis of the compensation was performed which emphasized on the movement relation between the moving camera and optical field, and a MOF Model was given to show the characterization of the overall movement of the scene. With the camera movement speculated by the overall movement, optical flow constraints were deduced to exclude the parallax false alarm by projective geometry from the perspective of the moving camera. At the end, experiments were performed based on actual image data. And the results compared with other algorithms show that this model is practical under the translation and rotation of camera.