View Full Version : Bit Depth and Resample DSP

04-08-2008, 08:28 AM
I have few questions related to Bit Depth and Resample DSP effects.

1. If I specify -dspeffect1="Bit Depth=-mindepth={qt}16{qt} -maxdepth={qt}16{qt}" would this mean that sources that are already in 16 bits won’t be touched but other sources e.g. 24 bits will be converted? This is what I would need.

2. When converting bit depth from e.g. 24 to 16, what method (dither) is used?

3. When converting sample rate e.g. from 88200 to 96000, what method s used?

4. When converting sample rate from higher to lower where higher is a whole multiple of lower e.g. from 88200 to 44100, what method is used?


04-08-2008, 09:45 AM
Yes 16 bit is left. Currently no dither is used. If Professional frequncy conversion is enabled then SSRC is used (one of the best) for all frequency conversions.

04-08-2008, 10:34 AM
Many thanks for the answer, Spoon.

I asked about bit depth because your ALAC encoder currently supports only 16 bits. I have some material in 24 bits that I would like to have in ALAC too. My experiments with importing 24 bits wave into iTunes and then converting to ALAC show that 24 bits are supported both in iTunes and in ALAC file format itself. Therefore, let me rephrase the question. Is 24 bits support in your ALAC encoder planned or in the works?

Ditto for SR – 48000, 88200, and 96000 are interesting besides the usual 44100.