Re: [SoX-users] Beginner / Combining lowpass filter with resample

[Ulrich K. <ul...@ch...>]

Thorsten Göllner <tg...@ov...>:

> I used sox to convert WAV-Files to 
> VOX-Files in earlier version with the following command:
> sox input.wav -r 8000 -c1 output.vox lowpass 4000 resample
> But with the current version 14.4.0 I get the following error:
> sox FAIL lowpass: usage: [-1|-2] frequency [width[q|o|h|k]](0.707q)
> Where is my fault, please?

Ah, the error message is somewhat misleading. The problem is not the lowpass, but the resample effect: It has been superseded by rate.

So you could replace "lowpass 4000 resample" with "lowpass 4000 rate", or even leave out rate because it will be added automatically when needed ("lowpass 4000"). And actually, rate does its own filtering, so you can omit the lowpass, too. :-)

(Regarding the error message: SoX thinks that you specified a second argument to the lowpass effect, namely, "resample", which of course isn't valid syntax.)

Ulrich