6 件 利用可能
Members of several working groups within the ISO Technical Committee 42 (photography) have begun addressing the important topic of providing guidance for which skin tones to use for image quality testing in various photographic applications.
Noise Equivalent Quanta (NEQ) is an objective Fourier metric which evaluates the performance of an imaging system by detailing the effective equivalent quanta of an exposure versus spatial frequency.
The latest transparent and objective mobile phone test scheme
Machine-vision systems rely on accurate sensor characterization, yet the EMVA 1288 standard's use of monochrome illumination raises important questions about real-world comparability. This study examines how different light sources influence key measurement results and shows that only quantum efficiency and related parameters are affected. Using broadband illumination can therefore offer more practical insight into application-specific performance.
Diffractive-optics-based geometric camera calibration has opened the door to highly compact, easy-to-use setups capable of capturing precise dot-grid patterns from virtual infinity. This paper explores the method's untapped potential, from extreme wide-FOV calibration to large entrance pupils and automotive distances, while addressing key limitations such as infinity-only measurement and chromatic constraints. Several practical solutions are presented to extend the technique beyond distortion measurement toward richer system characterization.
Noise reduction in digital cameras significantly affects image quality by reducing low-contrast details, often perceived as texture blur. This study compares different spatial frequency response (SFR) measurement methods, showing that adaptive filtering leads to varying results depending on the test target. The differences between methods are analyzed to better characterize how noise reduction impacts specific spatial frequency bands.