针对现有基于ADV212压缩系统的ADV212控制器难以满足空间TDICCD相机的应用，提出了一种适于大视场空间TDICCD相机的高性能ADV212控制器。首先，分析了ADV212工作原理，结合CCD数据特点，提出了Custom-specific模式工作机制，在该机制下，使用乒乓操作的SDRAM构造图像帧，并以流水线作业的方式实现单片ADV212处理5通道CCD数据。最后，使用地面检测设备对ADV212控制器进行了试验验证。结果表明，ADV212控制器能快速稳定地工作，压缩一帧图像仅需7.68 ms。在压缩比指标2：1～32：1内，PSNR均在30 dB以上，在正常工作压缩比为1 bpp时平均PSNR提高了2.49 dB。该控制器满足了空间相机压缩系统的应用。%Because ordinary ADV212 controllers of compression scheme based on ADV212 cannot satisfy the demands of space camera, a high performance ADV212 controller for space camera is proposed in this paper. The working principle of ADV212 is first analyzed and then a working mechanism of custom-specific mode is presented. In the custom-specific mode, the frame is constructed by using the ping-pong operation of SDRAM and an ADV212 is applied to compress five-channel CCD data by pipelining. The interface among CCD, ADV212 and SDRAM is managed by interrupt handling strategy. Moreover, the three parameters which affect the quality of image compression are analyzed. The verification experiments to ADV212 compression system show that compression system works fast and stably. The time needed in compressing a frame image is only 7.68 ms, all PSNRs are more than 30 dB in the compression ratio of 2:1 to 32:1, and the average PSNR is increased by 2.49 dB in the lossy compression mode when the compression ratio is 1 bpp. The performances of the proposed controller effectively meet the requirement of applications of the large field of view TDICCD space camera.
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