Blob Bindings using Stream

function.json

{
  "bindings": [
    {
      "name": "myBlob",
      "type": "blobTrigger",
      "direction": "in",
      "path": "incontainer/{name}",
      "connection": "buchifunctions_STORAGE"
    },
    {
      "type": "blob",
      "name": "outputBlob",
      "path": "outcontainer/{name}",
      "connection": "buchifunctions_STORAGE",
      "direction": "out"
    }
  ],
  "disabled": false
}

sample1.csx

using System;

public static void Run(Stream myBlob, Stream outputBlob, TraceWriter log)
{
    using(var sw = new StreamWriter(outputBlob))
    {
        myBlob.CopyTo(outputBlob);
    }
}