[libdvdcss-devel] Any way to improve brute force?

[Reimar Döffinger]

On 10.03.2016, at 10:57, Christian Pernegger <pernegger at gmail.com> wrote:
> Hi,
> 
> My understanding was that libdvdcss would fall back to a brute force
> "title" method if presented with data on a filesystem or an RPC2 drive
> not set to the correct region. I'd have expected that process to take
> some serious time, but it doesn't, it fails almost immediately (couple
> of seconds at most). Is there any way to improve the title method,
> e.g. give it more time or additional info?

The cases I know of only fail on short titles, like copyright warnings (the irony!).
For brute-forcing it then gets a bit difficult since you are short of bits with known values so then you'd probably need a bit of video stream parsing code to check that you got the right key (I think).
In many cases however that is not necessary: you can get the key of the longest title and then you check the same key and +- a few values.
That would work for almost half of my DVDs.
Quite a few have just c0:00:00:00:0? as keys actually.
Besides all that, there is a chance someone looking closely might actually simply find bugs in the code that would improve things.