Self-synchronizing variable-length codes for image transmission

Variable-length codes are vulnerable to loss of synchronization if they are transmitted through a noisy channel. In order to achieve synchronization regardless of the preceding synchronization slippage, the concept of extended synchronizing codewords is introduced. An iterative algorithm is proposed to design extended synchronizing codewords efficiently. The extended synchronizing codewords are placed in fixed positions of an image to control error propagation due to synchronization slippage. However, the image can still be partially corrupted by channel noises. An error concealment method to further improve the image quality is discussed