What does the filter parameter to createScaledBitmap do?

android scaling
clahey picture clahey · May 24, 2010 · Viewed 53.1k times · Source

The declaration of android.graphics.Bitmap.createScaledBitmap is

public static Bitmap createScaledBitmap
  (Bitmap src, int dstWidth, int dstHeight, boolean filter)

However, the documentation doesn't explain any of the parameters. All of them are pretty obvious except for boolean filter. Does anyone know what it does?

Answer

teedyay picture teedyay · Oct 5, 2010

To expand on Karan's answer: As a general rule you won't see any difference if you're scaling your image down, but you will if you're scaling it up.

Passing filter = false will result in a blocky, pixellated image.

Passing filter = true will give you smoother edges.

However, as EIYeante pointed out in the comments, you might still see a difference. This is their example image.

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