Normalize is faster than without it

[ADLANCAS]

Hi,
A simple line Normalize(last,0.8) is faster than without this command.:confused:
Using avs2wav, it takes in my example to create a wave file:
14 seconds (with Normalize)
20 seconds (without)
Someone could confirm that?
Thanks,

Alexandre

[Didée]

And how long is the difference in time needed to open the script? :)

[ADLANCAS]

I used a script with 200.000 frames and opened in VDubMod.
I couldn´t see any difference:confused:

[Didée]

Ah yes, nothing to notice when opening the script, because of

>> The calculation of the peak value is done the first time the audio is
>> requested, so there will be some seconds until AviSynth continues.

I'm suspecting that a good part of the audio data is still cached after Normalize() has seeked through, so that the subsequent saving gets a good burst.

[ADLANCAS]

It can be.

[WarpEnterprises]

Furthermore the internal audio-caching is enabled by normalize and maybe there is a helpful samplesize conversion done.

[IanB]

In the latest AVS Normalize() uses a 256K transfer buffer to prescan the input stream, so it will load the cache damn fast. If the target application uses a small buffer that ends up not being disk sector aligned for the ultimate disk reads, this could give a marked performance boost.

EnsureVBRMP3Sync() also got the 256K transfer buffer code upgrade. It won't prescan the input stream yet could give a similar boost depending on the targat access pattern.