[LAD] precision resampling to correct clock differences - no luck with libsamplerate and zita-resampler...

Erik de Castro Lopo mle+la at mega-nerd.com
Sat May 22 22:52:16 UTC 2010


Jörn Nettingsmeier wrote:

> i found that. but when i'm trying with sndfile-resample (using the -by
> parameter), i get an integer target sample rate (or at least, that's
> what the output claims),

Thats a limitation of libsndfile, not libsamplerate. libsndfile only
allows integer samplerates. Of all the sound file formats libsndfile
supports, only AIFF supports floating point sample rates.

> which is what confused me. plus it seems that
> the target sample rate in the SRC structure is an int, not a double, so
> i don't understand how arbitrary ratios could be represented...

In sndfile-resample.c :

    else if (strcmp (argv [k], "-by") == 0)
    {   k ++ ;
        src_ratio = atof (argv [k]) ;
        }

and that value is passed unmolested to libsamplerate.

However, the samplerate of the output file is still an integer.

> >   b) Internally, the time distance between samples is also calcutated
> >      in double floating point.
> 
> great. so it looks like a minor hack to sndfile-resample to get what i want.

I really don't think any modification is necessary.

Erik
-- 
----------------------------------------------------------------------
Erik de Castro Lopo
http://www.mega-nerd.com/



More information about the Linux-audio-dev mailing list