Java tutorial
//package com.java2s; //License from project: Open Source License import android.graphics.Bitmap; import android.graphics.Bitmap.Config; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.PorterDuff.Mode; import android.graphics.PorterDuffXfermode; import android.graphics.Rect; import android.graphics.RectF; public class Main { public static Bitmap toRoundBitmap(Bitmap bitmap) { if (bitmap == null) { return null; } int width = bitmap.getWidth(); int height = bitmap.getHeight(); float roundPx; float left, top, right, bottom, dst_left, dst_top, dst_right, dst_bottom; if (width <= height) { roundPx = width / 2; top = 0; bottom = width; left = 0; right = width; height = width; dst_left = 0; dst_top = 0; dst_right = width; dst_bottom = width; } else { roundPx = height / 2; float clip = (width - height) / 2; left = clip; right = width - clip; top = 0; bottom = height; width = height; dst_left = 0; dst_top = 0; dst_right = height; dst_bottom = height; } Bitmap output = Bitmap.createBitmap(width, height, Config.ARGB_8888); Canvas canvas = new Canvas(output); final int color = 0xff424242; final Paint paint = new Paint(); final Rect src = new Rect((int) left, (int) top, (int) right, (int) bottom); final Rect dst = new Rect((int) dst_left, (int) dst_top, (int) dst_right, (int) dst_bottom); final RectF rectF = new RectF(dst); paint.setAntiAlias(true); canvas.drawARGB(0, 0, 0, 0); paint.setColor(color); canvas.drawRoundRect(rectF, roundPx, roundPx, paint); paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); canvas.drawBitmap(bitmap, src, dst, paint); if (null != bitmap) { bitmap.recycle(); bitmap = null; } return output; } }