How to decode the SAML request

Hi All ,

I am trying to integrate Saleforce.com with AD FS 2.0.

Both AD FS Idp and Salesforce SP links are working fine.

I need to do few customizations on ADFS login to display client company logo.

For this I want to read the “Audience” value from incoming  SAMLRequest.

I have tried with below piece of code:

    String mySAMLRequest ="xxxxyyyyzzzz”;

    MemoryStream memStream = new MemoryStream(Convert.FromBase64String(mySAMLRequest));

    memStream.ReadByte();

    memStream.ReadByte();

    DeflateStream deflate =newDeflateStream(memStream,CompressionMode.Decompress);

    string myDoc =newStreamReader(deflate, System.Text.Encoding.UTF8).ReadToEnd();

 but I am getting the below error with my SAMLRequest.

“Unknown block type. Stream might be corrupted."

Can anybody tell me how I can decode this SAMLRequest and read “Audience” attribute value.

<Audience>https://xxx.abc.salesforce.com</Audience>

Or is there any other way to read this "Audience value" from SAMLRequest

My link is as below: