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resize-filter

The resize-filter parameter enables control over the resizing filter used to generate a new image with a higher or lower number of pixels.

Syntax

resize-filter={value}

Allowed values

ValueDescription
nearestUses the value of nearby translated pixel values.
bilinear (or linear)Uses an average of a 2x2 environment of pixels.
bicubic (or cubic)Uses an average of a 4x4 environment of pixels, weighing the innermost pixels higher.
lanczos2Uses the Lanczos filter to increase the ability to detect edges and linear features within an image and uses sinc resampling to provide the best possible reconstruction.
lanczos3( or lanczos)Lanczos3 uses a better approximation of the sinc resampling function. (Default)

Notes

  1. When making an image smaller, use bicubic, which has a natural sharpening effect.
  2. When making an image larger, use bilinear, which has a natural smoothing effect.
  3. When resizing pixel art, use nearest, which has a natural pixelation effect.
  4. When quality is the main concern, use lanczos, which typically renders the best results.

Examples

Click the links to view the transformed image using a demo Fastly IO service.

Example usageDescription
?resize-filter=bilinearDeliver an image that has been resized using the bilinear filter.