[FFmpeg-devel] [PATCH] AMR-WB Decoder

Marcelo Galvão Póvoa marspeoplester
Sun Sep 19 03:48:05 CEST 2010

On 18 September 2010 22:27, Ronald S. Bultje <rsbultje at gmail.com> wrote:
> Hi,
> 2010/9/18 Marcelo Galv?o P?voa <marspeoplester at gmail.com>:
>> Ok, I tried using the av_mlfg_get() instead of the av_lfg_get() PRNG
>> and the output stddev is higher than I would expect. So the cause of
>> the deviation against the reference decoder may be that.
> What "random" number generator does the ref decoder use? Is it an algo
> that you can copy, or is it literally "random()"?

It is simple:

Word16 D_UTIL_random(Word16 *seed)
   /*static Word16 seed = 21845;*/
   *seed = (Word16)(*seed * 31821L + 13849L);


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