[PD] Re: size of loaded audio to array

[Thomas Grill]

Hi Derek,

> So how much RAM does a 3 minute, stereo, 16-bit file @ 44100 Hz actually
> take up when loaded into a single-channel, 1323000-element [30 sec @
> 44100 Hz] array? Seems like a simple math question, but I feel like I
> don't have all the factors figured in yet...

- if you don't use soundfiler's -resize flag the array size won't change,
meaning that the array will take up about 1,3 MSamples *4 bytes = 5,2
Mbytes.
- when using the -resize flag and reading in one channel of the stereo file
that would result in about 8 MSamples *4 bytes= 32 MBytes. Please note that
there's also some built-in limit (that i have cancelled out in my PD version
and that can also be overridden by some soundfiler flag) chopping the sound
file and restricting the load process to 4 MSamples = 16 MBytes.

There's a shorthand form to these calculations:
1 minute of 32 bit mono data (or 16 bit stereo data) at 44,1 kHz takes up
about 10 MBytes.

> [Bonus question: would it
> make a difference if PD were using 48 Khz?]

No, that just influences eventual playing speed. Loaded sound data is not
resampled, so a 44.1 kHz sound file will sound pitched higher when played
with tabplay~.

best greetings,
Thomas