Robust still image coding using lapped transforms with block classification
نویسندگان
چکیده
Very efficient still image compression methods exist today, but most of them are not fit for transmission on error prone channels. One example of state-of-the-art robust image coding is the use of wavelet compression followed by forward error correction (FEC), as proposed by Sherwood and Zeger, that gives high coding efficiency but suffers from the incomplete decoding problem. An alternative to this is the joint source/channel coding scheme by Chen and Fischer, which overcomes this difficulty at the expense of a lower PSNR performance. In this paper we propose a joint source/channel coding scheme with increased coding efficiency based on lapped transforms with block classification. With an efficient bit allocation strategy and the high coding gain of Lapped Transforms, a significant increase, on the order of 2 dB, in the PSNR versus BER performance has been obtained over the classical joint source/channel scheme on binary symmetric channels.
منابع مشابه
Source/Channel Coding of Still Images Using Lapped Transforms and Block Classification
A novel scheme for joint source/channel coding of still images is proposed. By using efficient lapped transforms, channel-optimized robust quantizers and classification methods we show that significant improvements over traditional source/channel coding of images can be obtained while keeping the complexity low.
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