Power spectrum curve compensation method for image quality enhancement in high-throughput gene sequencing.

Abstract

In high-throughput gene sequencing, the quality of sequencing images is critical for the accuracy of subsequent base calling. However, during practical sequencing processes, the time delay integration (TDI) camera's push-scan imaging often leads to significant degradation of image quality along the push-scan direction. Addressing the current limitations in TDI image restoration research for gene sequencing, this study establishes an imaging spectrum model of sequencing images based on MGI's ultra-high-throughput sequencer. We systematically analyze the causes and intrinsic mechanisms of image quality degradation, with a focus on elucidating the specific impacts of TDI push-scanning on image quality. To enhance TDI sequencing image quality, we compare the differences in power spectral projection curves between stare-mode imaging and TDI push-scan imaging and propose a power spectrum curve compensation (PSCC)-based quality optimization method alongside a novel evaluation framework for sequencing image quality. Experimental results demonstrate that compared to original H-channel images from cycle 1 to 50, the energy concentration (1/σ) of the optimized images increases by 9.13% in the TDI direction and 4.64% in the direction perpendicular to TDI. Signal-to-noise ratio (SNR) increases by 6.90% for base A and 4.99% for base C, while base calling accuracy (Q30) improves by 1.67%.