[Ffmpeg-devel] [RFC] av_random...

Reimar Doeffinger Reimar.Doeffinger
Wed Jan 10 09:53:48 CET 2007

On Tue, Jan 09, 2007 at 05:03:20PM -0600, Ryan Martell wrote:
> On Jan 9, 2007, at 4:47 PM, Michael Niedermayer wrote:
> >On Tue, Jan 09, 2007 at 04:03:21PM -0600, Ryan Martell wrote:
> >[...]
> >>For the record, the timing units I sent before were only timing the
> >>generate_untempered function, since it's only called every
> >>AV_RANDOM_N times av_random is called.
> >>
> >>Final question: typically, I use time(NULL) to initialize the seeds
> >>of a random number generator.  Since ffmpeg says don't use time
> >>(NULL), what's the best pseodo-random seed generator to use?
> >
> >0 should do
> Not really; then it won't be even random- the GUID of everyone (in  
> asf.c for my mms stuff, that started this all), will always be the  
> same for every user out there.  The seed must be initialized with  
> something that's at least pseudo random.

In how far is that a problem? Using truly random numbers is both a
privacy concern and a problem for regression test, so IMO they should be
avoided by any means necessary, if really necessary maybe adding an
option to enable them...

Reimar D?ffinger

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