Java tutorial
//package com.java2s; import java.io.ByteArrayOutputStream; import android.graphics.Bitmap; public class Main { public static byte[] getBitmapToBytes(Bitmap bitmap) { if (bitmap != null) { ByteArrayOutputStream baos = new ByteArrayOutputStream(); bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos); return baos.toByteArray(); } return null; } }