QVZ: lossy compression of quality values

Motivation: Recent advancements in sequencing technology have led to a drastic reduction in the cost of sequencing a genome. This has generated an unprecedented amount of genomic data that must be stored, processed and transmitted. To facilitate this effort, we propose a new lossy compressor for the...

Full description

Bibliographic Details
Authors: Hernaez-Arrazola, M. (Mikel)|||/items/954a4ee7-b04c-4dc5-9bfc-7a48332c7e5a, Malysa, G. (Greg)|||/items/cf0737b3-3bb8-4468-911d-15ece013ca1a, Ochoa-Álvarez, I. (Idoia)|||/items/6326dacc-419f-4156-a9c3-9e79cfcc6a3c, Rao, M. (Milind)|||/items/60e2d226-680e-4810-a09a-5dc14f72fb4c, Ganesan, K. (Karthik)|||/items/04319347-2895-42d8-ac5b-870459537f1f, Weissman, T. (Tsachy)|||/items/a0d863e4-764e-4234-90c7-37fb482a34c5
Format: article
Publication Date:2015
Country:España
Institution:Universidad de Navarra
Repository:Dadun. Depósito Académico Digital de la Universidad de Navarra
Language:English
OAI Identifier:oai:dadun.unav.edu:10171/113610
Online Access:https://hdl.handle.net/10171/113610
Access Level:Open access
Keyword:QVZ
Lossy compression
Quality values
Description
Summary:Motivation: Recent advancements in sequencing technology have led to a drastic reduction in the cost of sequencing a genome. This has generated an unprecedented amount of genomic data that must be stored, processed and transmitted. To facilitate this effort, we propose a new lossy compressor for the quality values presented in genomic data files (e.g. FASTQ and SAM files), which comprise roughly half of the storage space (in the uncompressed domain). Lossy compression allows for compression of data beyond its lossless limit. Results: The proposed algorithm QVZ exhibits better rate-distortion performance than the previously proposed algorithms, for several distortion metrics and for the lossless case. Moreover, it allows the user to define any quasi-convex distortion function to be minimized, a feature not supported by the previous algorithms. Finally, we show that QVZ-compressed data exhibit better performance in the genotyping than data compressed with previously proposed algorithms, in the sense that for a similar rate, a genotyping closer to that achieved with the original quality values is obtained.