A new technique to recover the information loss in a block-based image coding system is developed in this paper. Disk arrays organize multiple, independent disks into a large, high-performance logical disk. However, with more devices, reliability drops. A single disk failure in RAID level 5 will lead to the increase of the load of each surviving disk by 100% for data reconstruction. Each disk is loaded at less than 50% of its capacity in the fault-free state so that the surviving disks will not saturate when failure occurs. By image partitioning, decoder reconstructs DCT blocks in the sub-image and does not impose any significant load on the disk array. Our approach improves the quality of the compressed image by 2dB to 10dB and above and reduces the code overhead of the compressed image data by 2 percent to 10 percent and above for different images due to recovering main AC coefficients.