Search found 55 matches

by tobiasherzke
Fri Apr 16, 2021 11:28 am
Forum: Connect openMHA to Matlab
Topic: edit openMHA code and get private variables
Replies: 8
Views: 317

Re: edit openMHA code and get private variables

Two possibilities:

1. Use a debugger, set breakpoints, display the variables you are interested in.

2. Hack the source code to export the data that you are interested in in some suitable form, recompile.

It's all open source after all.
by tobiasherzke
Thu Apr 15, 2021 7:26 pm
Forum: Connect openMHA to Matlab
Topic: edit openMHA code and get private variables
Replies: 8
Views: 317

Re: edit openMHA code and get private variables

Not every C++ variable that you find in the source code of the plugins is exported to the configuration tree, and therefore not every C++ variable is accessible from Matlab. You can find the accessible configuration variables for each plugin in the plugin manual, http://www.openmha.org/docs/openMHA_...
by tobiasherzke
Wed Apr 14, 2021 4:34 pm
Forum: Connect openMHA to Matlab
Topic: edit openMHA code and get private variables
Replies: 8
Views: 317

Re: edit openMHA code and get private variables

Please clarify what you want to achieve, e.g. by giving an example of the desired outcome.
by tobiasherzke
Fri Mar 05, 2021 1:59 pm
Forum: User Applications
Topic: Questions about time constants in dynamic compressor dc
Replies: 8
Views: 536

Re: Questions about time constants in dynamic compressor dc

Yes the conversion to dB is done by MHASignal::pa22dbspl. See its documentation here: http://mha.hoertech.de/doc/master/namespaceMHASignal.html#adffb46b90b6e9460f06286bda1c6d1de mha_real_t MHASignal::pa22dbspl ( mha_real_t x, mha_real_t eps = 0.0f ) inline Conversion from squared Pascal scale to dB ...
by tobiasherzke
Wed Mar 03, 2021 5:11 pm
Forum: User Applications
Topic: Questions about time constants in dynamic compressor dc
Replies: 8
Views: 536

Re: Questions about time constants in dynamic compressor dc

Computation of level from signal in openMHA does not need to know the peaklevel that you configured in plugin transducers. To understand how the level computation from STFT spectra works in openMHA, you need to be aware of two openMHA properties: 1) Central calibration. Because hearing aid signal pr...
by tobiasherzke
Sat Feb 27, 2021 2:55 pm
Forum: User Applications
Topic: Questions about time constants in dynamic compressor dc
Replies: 8
Views: 536

Re: Questions about time constants in dynamic compressor dc

Checking Release Times (I use the words "decay" and "release" interchangeably in this thread.) Classic dynamic compressors in hearing aids often use a significantly longer release (or decay) time constant than attack time constant. The purpose of both time constants is to stabilize gain applied to ...
by tobiasherzke
Sat Feb 27, 2021 1:17 pm
Forum: User Applications
Topic: Questions about time constants in dynamic compressor dc
Replies: 8
Views: 536

Re: Questions about time constants in dynamic compressor dc

A quick addition how we test the time constants in unit tests: We use a very similar setup to what I did in my previous post: set all filter time constants to 0 except for the one that I want to test, then simulate a step response. But instead of directly querying the filtered output levels, I allow...
by tobiasherzke
Sat Feb 27, 2021 1:11 pm
Forum: User Applications
Topic: Questions about time constants in dynamic compressor dc
Replies: 8
Views: 536

Re: Questions about time constants in dynamic compressor dc

Reproducing your attack time . Analyzing your graph: You have probably used an attack time constant of exactly 1 second to produce this graph (see analysis at bottom of this post). This is a very long attack time constant and not suitable for normal hearing aids, but openMHA is very flexible and ca...
by tobiasherzke
Fri Feb 26, 2021 7:30 pm
Forum: User Applications
Topic: Questions about time constants in dynamic compressor dc
Replies: 8
Views: 536

Re: Questions about time constants in dynamic compressor dc

The dynamic compressor dc can be configured with 3 different time constants for each frequency band. All three time constants are the time constants(*) of first-order low-pass filters that filter the input level of the frequency band for which they are specified: tau_rmslev - This time constant is o...