Algorithm and Architecture Design of Image Inpainting Engine for Video Error Concealment Applications

Error concealment techniques can improve subjective video quality in a decoder when the video bitstream is corrupted during transmission. In this paper, to achieve perceptually pleasant results, an image inpainting technique in which structure information generated from edge information is adopted as the spatial error concealment method. In addition, a modified boundary matching algorithm for temporal error concealment is proposed for temporal frames. To maintain low hardware costs as regards the error concealment engine, the processing iteration number of each macroblock is limited to four based on the proposed inpainting algorithm. Block-based pipeline scheduling is also proposed to reduce the number of processing cycles and the on-chip memory size. Moreover, a cache-based data reuse scheme is developed to reduce the processing cycles and external bandwidth. Moreover, the two concealment modes share the same computational core to reduce hardware costs. A prototype chip is implemented by using the UMC 90 nm process. The total gate count is approximately 121 k at 200 MHz. The maximum processing capability can support 244.8 k macroblocks per second or 1920 × 1080 4:2:0 30 Hz video. The core size is 1.30 × 1.30 mm². The average power dissipation is 131.4 mW at 200 MHz. Compared to other error concealment methods, the proposed design can achieve better perceptual quality at an acceptable additional hardware cost.