RederScript ScriptIntrinsicConvolve3*3 sharpen is not working on api 28-29

[raghunandankavi2010]

The screens shots in your demo talk actually applies filters to the lena image you have in drawable resource.
However when i tried the same code with the same image on my pixle2xl the sharpen and the original looks same. Similarly the blur and original image looks same.
I have tried this with multiple images and it looks all the same.

Demo Video : https://drive.google.com/open?id=1kiMVmJ08D0sxREOGuHRBzpI__Ga_BWsx
Pixel2 emualtor.

I have also read blogs and talks by rebecca franks on renderscript which is available on youtube.
https://www.youtube.com/watch?v=hUHaJIXWc-k&ab_channel=GDGLviv.

Also is there any hint on how these filters values are got ie the matrix values. I know its available online. But would like to know more if you can point me to some resources.
Your talk is old but very relevant and helpful. Thanks.