If you choose to resize by pixels, enter the new height and width of the processed images. If you want to maintain the aspect ratio, enter 0 for either the height or width.
E.g. if the source image is 1200 pixels high and 800 pixels wide, and you enter the new height as 600 pixels and 0 for the new width, the image will be resized to 400 pixels high and 400 pixels wide.
You can also choose to resize the longest side to a specific size while maintaining the image's aspect ratio. The 'new size' value is applied to the longest side. This option is useful when you have a mix of both portrait and landscape orientated images, and you want the longest side to be of a specific size.
During the resizing process, you can also apply filters to control the quality of the resized images. Hermite, Bell, BSpline, Lanczos3, Mitchell, Nearest, Bilinear, and Bicubic filters produce good quality images, while Triangle, Linear, and FastLinear filters are fast.