question: public static void scaleFit ( Bitmap src , Bitmap dest , int clearColor ) { float ratio = Math . min ( dest . getWidth ( ) / ( float ) src . getWidth ( ) , dest . getHeight ( ) / ( float ) src . getHeight ( ) ) ; int newW = ( int ) ( src . getWidth ( ) * ratio ) ; int newH = ( int ) ( src . getHeight ( ) * ratio ) ; int paddingTop = ( dest . getHeight ( ) - ( int ) ( src . getHeight ( ) * ratio ) ) / 2 ; int paddingLeft = ( dest . getWidth ( ) - ( int ) ( src . getWidth ( ) * ratio ) ) / 2 ; scale ( src , dest , clearColor , 0 , 0 , src . getWidth ( ) , src . getHeight ( ) , paddingLeft , paddingTop , newW + paddingLeft , newH + paddingTop ) ; }
target:  Scaling src Bitmap to fit and cenetered in dest bitmap. Method keep aspect ratio.