[FFmpeg-devel] Detecting encrypted DVDs

Reimar Döffinger Reimar.Doeffinger
Sat Jan 10 14:41:08 CET 2009

On Sat, Jan 10, 2009 at 01:26:03PM +0000, M?ns Rullg?rd wrote:
> Encrypted DVDs give low-level read errors unless the drive has been
> properly set up, e.g. by libdvdcss.  I don't know of anything unlocks
> the drive without also decrypting the stream.

Hm? I think at most RPC-2 drives do that, and in addition anyone who applied
region-free firmware modifications should probably have a drive acting
like RPC-1.

> There are of course other sources of encrypted MPEG streams than DVDs.
> The ISO spec does not assign any meaning to the scrambling control
> field, and we've seen files that set it to a non-zero value even
> though there is no encryption, so acting on this field is not
> reliable.

Well, if someone wants to do the effort, I think a one-time warning
message that it might be encrypted would be acceptable.

Reimar D?ffinger

More information about the ffmpeg-devel mailing list