[FFmpeg-devel] [PATCH] Deterministic Noise Generation option for audio codecs that involve noise generation (RNG)

Reimar Döffinger Reimar.Doeffinger at gmx.de
Mon Sep 9 09:07:12 CEST 2013

On 09.09.2013, at 08:32, Jonathan Campbell <jonathan at castus.tv> wrote:
> On 09/07/2013 08:09 PM, Michael Niedermayer wrote:
>> tabs are not allowed in ffmpeg git (except in Makefiles)
> Understood.
>> please dont add any flags, the flag systems is rather unflexible and
>> the number of flags limited to 32
> How will the program enable the DNG function then? Should I make it an AVOption?
>> md5 is slow, running it over the whole frame is overkill
>> libavutil/murmur3.c might be an alternative
> True. Any recommendations to take murmur3.c 16-byte output and fill the AVLFG state array with it? Should I repeat the 16-byte pattern 16 times or do some transformation to it on each iteration?

You can just use the lower 32 bits as seed...
Only slightly related: I still have an old patch to switch to lcg, making this code use a good bit less CPU time. Wonder if I should dig it out again, so far it has been stalled to death each time...

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