Tag Archives: Android Bitmap Image to byte[]

Convert Android Bitmap Image and iOS UIImage to byte[] array in Xamarin

Ever wanted to convert an Android Bitmap Image to dot net byte[] array ? or how about converting iOS UIImage to dot net byte[] array ? Ever wondered how to implement either ? 😉 Well then you are about to find out how!

Alright so there was this one time…

I wanted to create a Custom Image Loader service using Dependency Service in Xamarin Forms.

It’s suppose to be easy, but the only problem was getting the different Image types in Android and iOS to a common data type!??%$@##!! 😦

Byte[] array for the Rescue

So just like you would have assumed by now, I wanted to convert the both Android and iOS Image types to dot net byte[] array type so that I could use them in my PCL library for the Xamarin Forms project. More specifically converting Android Bitmap Image to byte[] array and iOS UIImage to byte[] array was my specific requirement.

Well, as usual here I am sharing the code implementation, incase if any of you are going through the same situation, here’s how I implemented it. 😉

Android Bitmap Image to byte[] array ?

It’s pretty straightforward, We create a Memory Stream and compress the Bitmap image into it as follows.

var ms = new MemoryStream();
// Converting Bitmap image to byte[] array
myBitmapImage.Compress(Bitmap.CompressFormat.Png, 0, ms);
var imageByteArray = ms.ToArray();


There you go, from the Memory Stream you extract the byte[] array.

iOS UIImage Image to byte[] array ?

In iOS first we create a blank byte[] array with the length sufficient to hold our Image’s size. We are going to use Marshal.Copy() method to copy our UIImage’s NSData.Bytes to our byte[] array as follows.

// Converting UIImage to byte[] array
Byte[] myByteArray = new Byte[myUiImage.Length];
System.Runtime.InteropServices.Marshal.Copy(myUiImage.Bytes, myByteArray, 0, Convert.ToInt32(myUiImage.Length));


Now pass around the myByteArray, wherever you want. lol

There you have it folks! 😀

Stay awesome!

Cheers! 🙂