Comparing Images In Sql Server

SELECT 1 where
HASHBYTES('MD5',image) =HASHBYTES('MD5', image)

or the following function 

CREATE FUNCTION [dbo].[fn_HashLongString] (@InputData NVARCHAR(MAX))

RETURNS BINARY(20)

AS

BEGIN

RETURN HASHBYTES('SHA1',SUBSTRING (@InputData,1,3989) + CAST(CHECKSUM(@InputData) AS NCHAR(11)))

END