Robust decoding of a 3D-ESCOT bitstream transmitted over a noisy channel

Abstract

In this paper, we propose a joint source-channel (JSC) decoding scheme for 3D ESCOT-based video coders, such as Vidwav. The embedded bitstream generated by such coders is very sensitive to transmission errors unavoidable on wireless channels. The proposed JSC decoder employs the residual redundancy left in the bitstream by the source coder combined with bit reliability information provided by the channel or channel decoder to correct transmission errors. When considering an AWGN channel, the performance gains are in average 4 dB in terms of PSNR of the reconstructed frames, and 0.7 dB in terms of channel SNR. When considering individual frames, the obtained gain is up to 15 dB in PSNR.

Joint source-channel coding/decoding of 3D-ESCOT bitstreams

“…Preliminary results have been obtained recently [22] for state-of-art DWTbased video coders such as Vidwav [4]. Recent entropy coders such as 3D-ESCOT [23] used in Vidwav leave only very little redundancy in the bitstream.…”

“…Finally, the robustness to transmission errors provided by the JSCD of the layered bitstream generated by the Vidwav coder is illustrated in Section IV. The performance improvements compared to a single-layer JSCD bitstream (see [22]) and to a classically decoded bitstream are illustrated in Section IV.…”

“…Trellis-based decoding technique such as that used in [24] cannot be applied here, since 3D-ESCOT cannot be easily represented by an automaton (from which the trellis is derived) with a manageable number of states. Thus, a sequential decoding approach [25] exploiting some coarse synchronization markers already present in the bitstream generated by the 3D-ESCOT has been used in [22]. Some improvements of the robustness to transmission errors of a single-layer version of the Vidwav coder have been observed.…”