HL-DNA: A Hybrid Lossy/Lossless Encoding Scheme to Enhance DNA Storage Density and Robustness for Images

With the storage's demand for high density and long-term preservation, Deoxyribonucleic Acid (DNA) has become a promising candidate to satisfy the requirement of archival storage for rapidly increased digital volume. However, due to the biochemical constraints, DNA storage faces critical issues of low practical capacity and robustness. In this paper, we target image applications and propose to apply approximation to DNA storage to improve the overall encoding density and robustness of DNA storage by using a hybrid lossy and lossless encoding scheme (called HL-DNA). Several lossy and lossless encoding schemes (lossy and lossless codes) are proposed and used to encode incoming binary sequences. These two types of codes are coordinated to balance the encoding density and errors. The lossless codes are used to limit the errors and the lossy codes are used to improve the encoding density. Moreover, the introduced approximation and newly proposed hybrid encoding schemes in one DNA strand can improve the robustness of DNA storage. Finally, the experimental results indicate that the proposed HL-DNA improves the encoding density of DNA storage and makes it much close to the ideal case. Also, HL-DNA achieves higher robustness to the injected errors than other DNA storage codes.