If you want to resize several album artworks at once, you can use the Batch Resize Artwork function.
Image Type: Choose the image type that the new resized image should be saved as.
JPEG Quality: This is used if the image type is Original and the original image is JPEG, or if the image type is JPEG. Higher quality results in better looking images but larger file sizes.
Image Dimensions: Allows you to enter new values for the width and height of the image. To resize the image by a percentage, choose "percent" form the pop-up menu.
Preserve Original Aspect Ratio: When this is checked, and the aspect ratio set in the width and height fields do not match the aspect ratio of the original image, Metadatics will alter the width or height to match the original aspect ratio. If this is not checked, the artwork will be resized to exactly the width and height that was entered.
Skip Tracks When Image Size Will Increase: If an artwork is smaller than than the entered width and height, that artwork will not be resized.