View Full Version : Detection of compression algorithm, how?

14-04-2008, 02:37 PM
Hi folks.

I am having a file stored in a binary format in a database. I know that it is compressed. However, I do not know what kind of algorithm has beed used to compress it. Anyone know a tool which would be helpful in the analyse of such file so I could decompress it?

Thanks for your suggestions.

Robert Kosek
14-04-2008, 04:15 PM
Usually in your SQL statement you call a compress or decompress function; what type of database are you using?

14-04-2008, 04:17 PM
depending on the budget it's probably zlib or gzip variant, depends on the age of file format.

14-04-2008, 06:13 PM
@Robert - I am using SQL Server 2000

@Delfi - zip would be my first guess too but I hoped that some tool could do the guessing job for me ;)

Robert Kosek
14-04-2008, 06:24 PM
Yes, it's probably based off ZLib, zip, or gzip. You'd have to look at the header of the blob without decompression to find out for certain.