First Principles' Imaging Performance Evaluation of CCD- and CMOS-based Digital Camera Systems

摘要

The new generation of digital still cameras (DSCs) is capable of capturing raw data that makes it possible to measure the fundamental metrics of the camera. Although CCDs are used in a majority of DSCs, the number of cameras with CMOS-based sensors is increasing. Using first principles, the performance of comparable CCD- and CMOS-based DSCs is measured. The performance metrics measured are electronic noise, signal-to-noise ratio, linearity, dynamic range, spatial resolution, and sensitivity. The dark noise and dark current are measured as a function of exposure time and ISO speed. The signal response and signal-to-noise response are measured as a function of intensity and ISO speed. The spatial resolution is measured in terms of the modulation transfer function (MTF) using both raw and rendered data. The spectral sensitivity is measured in terms of camera constants. Subjective image quality is also measured using scenes that exhibit limiting performance.