question: private static Bitmap transform ( Matrix scaler , Bitmap source , int targetWidth , int targetHeight , int options ) { Log . i ( TAG , "transform --1--" ) ; boolean scaleUp = ( options & 0x1 ) != 0 ; boolean recycle = ( options & 0x2 ) != 0 ; int deltaX = source . getWidth ( ) - targetWidth ; int deltaY = source . getHeight ( ) - targetHeight ; if ( ! scaleUp && ( deltaX < 0 || deltaY < 0 ) ) { Log . i ( TAG , "transform --2--" ) ; Bitmap b2 = Bitmap . createBitmap ( targetWidth , targetHeight , Bitmap . Config . ARGB_8888 ) ; Canvas c = new Canvas ( b2 ) ; int deltaXHalf = Math . max ( 0 , deltaX / 2 ) ; int deltaYHalf = Math . max ( 0 , deltaY / 2 ) ; Rect src = new Rect ( deltaXHalf , deltaYHalf , deltaXHalf + Math . min ( targetWidth , source . getWidth ( ) ) , deltaYHalf + Math . min ( targetHeight , source . getHeight ( ) ) ) ; int dstX = ( targetWidth - src . width ( ) ) / 2 ; int dstY = ( targetHeight - src . height ( ) ) / 2 ; Rect dst = new Rect ( dstX , dstY , targetWidth - dstX , targetHeight - dstY ) ; c . drawBitmap ( source , src , dst , null ) ; if ( recycle ) { source . recycle ( ) ; } c . setBitmap ( null ) ; Log . i ( TAG , "transform --3--" ) ; return b2 ; } float bitmapWidthF = source . getWidth ( ) ; float bitmapHeightF = source . getHeight ( ) ; Log . i ( TAG , "bitmapWidthF:" + bitmapWidthF + ",bitmapHeightF:" + bitmapHeightF ) ; float bitmapAspect = bitmapWidthF / bitmapHeightF ; float viewAspect = ( float ) targetWidth / targetHeight ; Log . i ( TAG , "targetWidth:" + targetWidth + ",targetHeight:" + targetHeight ) ; if ( bitmapAspect > viewAspect ) { float scale = targetHeight / bitmapHeightF ; if ( scale < .9F || scale > 1F ) { scaler . setScale ( scale , scale ) ; } else { scaler = null ; } } else { float scale = targetWidth / bitmapWidthF ; if ( scale < .9F || scale > 1F ) { scaler . setScale ( scale , scale ) ; } else { scaler = null ; } } Bitmap b1 ; if ( scaler != null ) { Log . i ( TAG , "transform --3.1--" ) ; b1 = Bitmap . createBitmap ( source , 0 , 0 , source . getWidth ( ) , source . getHeight ( ) , scaler , true ) ; } else { Log . i ( TAG , "transform --3.2--" ) ; b1 = source ; } if ( recycle && b1 != source ) { Log . i ( TAG , "transform --4--" ) ; source . recycle ( ) ; } int dx1 = Math . max ( 0 , b1 . getWidth ( ) - targetWidth ) ; int dy1 = Math . max ( 0 , b1 . getHeight ( ) - targetHeight ) ; Bitmap b2 = Bitmap . createBitmap ( b1 , dx1 / 2 , dy1 / 2 , targetWidth , targetHeight ) ; if ( b2 != b1 ) { if ( recycle || b1 != source ) { Log . i ( TAG , "transform --5--" ) ; b1 . recycle ( ) ; } } Log . i ( TAG , "transform --6--" ) ; if ( b2 == null ) { Log . i ( TAG , "transform --7--" ) ; } return b2 ; }
target:  Transform source Bitmap to targeted width and height