android programmatically blur imageview drawable

Question

I want to programmatically blur and unblur images in Android.

I hear that android flag \"blur\" is no longer supported after API 14 , but I wanted to use Java method

Answer 1

For blurring an imageView or bitmap, renderScript is used in conjunction with Picasso library.

public class Blur implements Transformation {
    protected static final int UP_LIMIT = 25;
    protected static final int LOW_LIMIT = 1;
    protected final Context context;
    protected final int blurRadius;


    public Blur(Context context, int radius) {
        this.context = context;

        if(radiusUP_LIMIT){
            this.blurRadius = UP_LIMIT;
        }else
            this.blurRadius = radius;
    }

    @Override
    public Bitmap transform(Bitmap source) {
        Bitmap sourceBitmap = source;

        Bitmap blurredBitmap;
        blurredBitmap = Bitmap.createBitmap(sourceBitmap);

        RenderScript renderScript = RenderScript.create(context);

        Allocation input = Allocation.createFromBitmap(renderScript, 
                sourceBitmap, 
                Allocation.MipmapControl.MIPMAP_FULL, 
                Allocation.USAGE_SCRIPT);



        Allocation output = Allocation.createTyped(renderScript, input.getType());

        ScriptIntrinsicBlur script = ScriptIntrinsicBlur.create(renderScript, 
                                    Element.U8_4(renderScript));

        script.setInput(input);
        script.setRadius(blurRadius);

        script.forEach(output);
        output.copyTo(blurredBitmap);

        source.recycle();
        return blurredBitmap;
    }

    @Override
    public String key() {
        return "blurred";
    }
}

Once you have added this class use the Picasso to blur the imageview or any bitmap

Picasso.with(context).load("load-from-whatever-source").transform(new Blur(context, 20)).into("wherever");

I found this answer in this blog.