Bit error recovery in internet facsimile without retransmission

This paper proposes a bit error recovery method for Internet facsimile images compressed with Group 3, Extended 2 Dimensional MMR coding scheme. When an error occurs in an MMR coded bitstream, the bitstream cannot be correctly decoded after the error point. To prevent losing valid information after an error, we developed an error recovery system that detects bit errors and applies bit-inversion algorithms to correct the errors. In case the bit-inversion cannot correct the error, the system applies new algorithms that utilize syntactical structure information of the coded bitstream. Testing results show that around 95% of bit errors are corrected with our bit-inversion algorithms. The error recovery system also recovers nearly all the data for the remaining 5% of the images.