- On the sender side, start with your image as a
byte[]
. - Convert the array to a text representation (a base64 string) using
Convert.ToBase64String(array)
. - Put that base64 string into the XML.
- On the receiver side, simply decode the base64 back to
byte[]
usingConvert.FromBase64String(string)
.
For details on each of those operations check this other post.