Abstract: In muon imaging technology, when plastic scintillating optical fibers are employed for detection, multiple sets of analog-to-digital conversion systems are required to process data in parallel. This study compared two digitization methods: ADC (Analog-to-Digital Converter) and QDC (Charge-to-Digital Converter). It was found that there is a strong linear correlation between the pulse amplitude output by the ADC and the charge integration output by the QDC, with a correlation factor reaching 0.9946. Further analysis revealed that the integration method used by the QDC exhibits stronger resistance to electronic noise. In contrast, the amplitude measurement approach of the ADC demonstrates greater effectiveness in reducing after-pulse interference as well as dark count interference induced by temperature variations. Under electronic noise conditions, the QDC achieves a signal-to-noise ratio (SNR) of 283, while the ADC only reaches 52. However, with simple filtering, the SNR of the ADC can be improved to 108. When subjected to after-pulse interference, the QDC yields measurement results that are excessively high, with data affected by after-pulses all lying above the fitting line. Under temperature interference, the probability of the QDC being affected by dark counts is higher than that of the ADC, and as the temperature rises, the dark count rate increases, making this difference even more pronounced. Given that systems combining plastic scintillating optical fibers with silicon photomultipliers are prone to a high number of after-pulses and dark counts, the ADC digitization method enables higher energy resolution and superior imaging performance. Therefore, in muon imaging applications, the ADC holds a distinct advantage over the QDC.