BASS.NET API for the Un4seen BASS Audio LibraryEncoderTooLAMETOOPsycModel EnumerationBASS.NET API for the Un4seen BASS Audio Library
The psychoacoustic model tooLAME should use (-1 to 4, default is 1).

Namespace: Un4seen.Bass.Misc
Assembly: Bass.Net (in Bass.Net.dll) Version: 2.4.12.0
Syntax

public enum TOOPsycModel
Members

  Member nameValueDescription
Default-2 Default model will be selected by encoder.
None-1 Psychoacoustic Model: -1 (turns off psycho-acoustic modelling and uses fixed default values instead)

This PAM doesn't actually look at the samples being encoded to decide upon the output values. There is simply a set of 32 default values which are used, regardless of input.

Pros: Faaaast. Low complexity. Surprisingly good. "Surprising" in that the other PAMs go to the effort of calculating FFTs and subbands and masking, and this one does absolutely nothing. Zip. Nada. Diddly Squat. This model might be the best example of why it is hard to make a good model - if having no computations sounds OK, how do you improve on it?

Cons: Absolutely no attempt to consider any of the masking effects that would help the audio sound better.

Fixed0 Psychoacoustic Model: 0

This PAM looks at the sizes of the scalefactors for the audio and combines it with the Absolute Threshold of Hearing (ATH) to make the 32 SMR values.

Pros: Faaast. Low complexity.

Cons: This model has absolutely no mathematical basis and does not use any perceptual model of hearing. It simply juggles some of the numbers of the input sound to determine the values.

ISO_PAM11 Psychoacoustic Model: 1

This PAM is from the ISO standard. Just because they are the standard, doesn't mean that they are any good. Look at LAME which basically threw out the MP3 standard psycho models and made their own (GPSYCHO).

Pros: A reference for future PAMs.

Cons: Terrible ISO code, buggy tables, poor documentation.

ISO_PAM22 Psychoacoustic Model: 2

This PAM is from the ISO standard. Just because they are the standard, doesn't mean that they are any good. Look at LAME which basically threw out the MP3 standard psycho models and made their own (GPSYCHO).

Pros: A reference for future PAMs.

Cons: Terrible ISO code, buggy tables, poor documentation.

PAM33 Psychoacoustic Model: 3

A re-implementation of psychoacoustic model 1. ISO11172 was used as the guide for re-writing this PAM from the ground up.

Pros: No more obscure tables of values from the ISO code. Hopefully a good base to work upon for tweaking PAMs.

Cons: At the moment, doesn't really sound any better than PAM1.

PAM44 Psychoacoustic Model: 4

A cleaned up version of PAM2.

Pros: Faster than PAM2. No more obscure tables of values from the ISO standard. Hopefully a good base to work from for improving the PAMs.

Cons: Still has the same "warbling"/"Davros" problems as PAM2.

See Also

Reference