Cannot display image in report builder from byte array or hex string

Hi, all,

I have a byte array (image) in json format in sql db. I extract the image out and also in json format. my query is:

SELECT thumbNail FROM Table
cross apply openjson(CMD_LIST,'$.queueMessagePages')
with
(pageNo Int '$.pageNo',
[thumbNail] nvarchar(max) as JSON
) as jsonsvalues where ...

 Then I get the thumbnail in nvarchar(max). 

In the report builder, I customize a function to convert the byte array into hex string. the function is like:

Function ToHexString(ByVal bytes() As Integer) As String
Dim strB As New System.Text.StringBuilder
Dim ints(bytes.Length) As Integer
Dim N as long
For N = 0 To bytes.Length - 1
If bytes(N) < 0 Then
ints(N) = bytes(N) + 256
Else
ints(N) = bytes(N)
End If
Next

For N = 0 To ints.Length - 1
If ints(N) < 16 Then
strB.Append("0" & Hex$(ints(N)))
Else
strB.Append(Hex$(ints(N)))
End If
Next

ToHexString ="0x" & Replace(strB.ToString().ToUpper(), " ", "")
Return ToHexString
End

I tried to run this function in vb,net can get the hex string correctly. but cannot get the image in report builder.

Please help to visualize the image in report builder if you have any experience. Thank you!

v-janeyg-msft