Friday 15th July 2022
So more colour theory and putting our plane in nuke. Gaussian filter or normal function. Lanczos filter. It's similar to Gaussian but notice the negative lobes. Look at PowerPoint for examples of filters. Use for filters: Box - computationally fast and gives a "boxy" look. Gauss - Gaussian lacks in sharpness but is good with ringing and aliasing. Bicubic - similar to bilinear but smoother interpolation. Sinc - keeps small details when scaling down with good aliasing. Ringing problems make it a questionable choice for scaling up. Has negative lobes. Lanczos - similar to Sinc filter but with less sharpness and ringing. Mitchell - a good balance between sharpness and ringing, so a good choice for scaling up. This is also know as a high quality Catmull-Rom filter triangle - also called tent - not highest quality but fine for displaying a scaled image on your screen. Convultion kernals. Convultion is the process of adding the local neighbors of a pixel together to form a new pixel value. Based on the weight of said neighbors in the form of a convultion kernal/matrix.
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