Java tutorial
//package com.java2s; import android.graphics.*; import android.graphics.Bitmap.CompressFormat; import android.graphics.Bitmap.Config; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream; public class Main { /** * Save PNG image with background color * @param strFileName Save file path * @param bitmap Input bitmap * @param nBackgroundColor background color * @return whether success or not */ public static boolean saveBitmapPNGWithBackgroundColor(String strFileName, Bitmap bitmap, int nBackgroundColor) { boolean bSuccess1 = false; boolean bSuccess2 = false; boolean bSuccess3; File saveFile = new File(strFileName); if (saveFile.exists()) { if (!saveFile.delete()) return false; } int nA = (nBackgroundColor >> 24) & 0xff; // If Background color alpha is 0, Background color substitutes as white if (nA == 0) nBackgroundColor = 0xFFFFFFFF; Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight()); Bitmap newBitmap = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888); Canvas canvas = new Canvas(newBitmap); canvas.drawColor(nBackgroundColor); canvas.drawBitmap(bitmap, rect, rect, new Paint()); OutputStream out = null; try { bSuccess1 = saveFile.createNewFile(); } catch (IOException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } try { out = new FileOutputStream(saveFile); bSuccess2 = newBitmap.compress(CompressFormat.PNG, 100, out); } catch (Exception e) { e.printStackTrace(); } try { if (out != null) { out.flush(); out.close(); bSuccess3 = true; } else bSuccess3 = false; } catch (IOException e) { e.printStackTrace(); bSuccess3 = false; } finally { if (out != null) { try { out.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return (bSuccess1 && bSuccess2 && bSuccess3); } }