Design of Image Stabilization System for Space Remote Sensor Based on DaVinci Technology

摘要

Many factors affect space remote sensor imaging, causing image degradation of contrast and resolution decreasing, which cannot be solved neither by improving resolution of imaging components nor processing of images. In order to meet the imaging requirement of space remote sensor, image stabilization system should be included. In this paper, with a combining method of micro-mechanical and digital image stabilization, an image stabilization system based on DaVinci technology is designed, including imaging and sensing unit, operating and controlling unit and fast steering mirror unit, using TI TMS320DM6446 as the main processor of the image stabilization system, which performs the function of focal plane controlling, image acquisition, motion vector estimating, digital image stabilization operating, fast steering mirror controlling and image outputting. The workflow is as followings: first, through optical system, ground scene is imaged by imaging focal planes. Short exposure images acquired by imaging focal plane are transferred as series to the unit of computing and controlling. Then, inter-frame motion vector is computed from images according to gray projection algorithm, and employed as inputs with image series to do iterative back projection. In this way the final picture is obtained. Meanwhile, the control value obtained from the inter-frame motion vector is sent to the fast steering mirror unit, making compensation to damp vibrations. The results of experiments demonstrate that the image stabilization system improves the imaging performance of space remote sensor.