Resampling

[prlin]

I use dbPoweramp to convert FLAC files to OPUS.
I have noticed that some OPUS files clip after being encoded to OPUS.
So I tried to use some DSP effects to avoid this.
I have set the resampler to 32 bit floating point and with TDPF dither.
But I have also thought of using the normalization function and lowering the level a couple of db (Desired Volume),
but I'm not sure which setting is best to avoid clipping. Is it Peak to Peak?
And what does the box where you can enter the maximum level mean? (Maximum Amplification X )
What is best practice in my case?

[Spoon]

Re: Resampling

DSP Bitdepth to Float
Volume Normalize Peak to Peak
Volume Normalize Fixed: -2dB

[prlin]

Re: Resampling

Thanks.
But there is one thing that still confuses me.
In the Volume Normalize dialog box, I find 6 alternatives, and I can´t chose both "Peak to Peak" and "Fixed Amplification" at the same time. Or can I?
Then I also wonder if I don´t have to set the resample to 48-khz in the resample dialog box? Can I exclude that?

[Spoon]

Re: Resampling

You would add a 2nd DSP effect Volume Normalize after the first

[prlin]

Re: Resampling

Thanks. Now I understand. And I don´t have to add resampling to 48 khz?

[Spoon]

Re: Resampling

It happens automatically to opus

[prlin]

Re: Resampling

It happens automatically to opus

I suppose OPUS inbuilt Speex resampler from xhip.org is used in this case.
If I would like to use bBpoweramps resampler instead, could I then put in resampling as DSP funktion after the normalization, or perhaps before the normalization?

Best Regards

[Spoon]

Re: Resampling

You could put resample before the Volume Normalize

[prlin]

Re: Resampling

Thanks. One more question so I understand and get this right.
My initial problem was that I observed some clipping after resampling. Not very frequent, but anyway.
My idea was to avoid this clipping when using normalization. If I resample before normalization, isn´t the normalization then wasted?
I mean, the clipping - if happening - I suppose then forego the normalization, the normalization no longer prevent it?
Or am I wrong?

[Spoon]

Re: Resampling

The first effect to float allows the values to go above clipping (+1), volume normalize would bring that back under

[prlin]

Re: Resampling

Thanks