This paper describes Slepian-Wolf codes based on overlapped quasi-arithmetic codes, where overlapping allows lossy compression of the source below its entropy. In the context of separate decoding, these codes are not uniquely decodable: the overlap introduces ambiguity in the decoding process leading to decoding errors. The presence of correlated side information at the decoder is used to remove this ambiguity and achieve a vanishing error probability. The state models and the automata of the overlapped quasi-arithmetic codes are described. The soft decoding algorithm with side information is then presented. The performance of these codes has been assessed first on theoretical sources and integrated in a distributed video coding platform.