view examples/puredata/xtract/xtract-help.pd @ 96:757e6f99dcd7

Dan Stowell: Removed strange "zeroing" part of xtract_mfcc() which was zeroing a load of elements despite the fact that they're ignored by the DCT process called next, and never used for anything. This was writing to an assumed large result array (same size as number of FFT bins) despite the fact that only a small number of MFCCs (typically less than 50) are required, therefore either wasting memory or writing to memory it shouldn't do!

#N canvas 685 60 450 725 10;
#X text 21 12 [xtract~];
#X text 24 19 ________;
#X text 22 52 [xtract~] provides a wrapper for the feature extraction
library: LibXtract. Please refer to the documentation at libxtract.sourceforge.net
\, for a full explanation of the library and the functions it provides.
Only the operation of the PD external will be explained here along
with a few use case scenarios.;
#X text 20 148 [xtract~] must always be called with one argument \,
in the following form: [xtract~ <feature>] \, where <feature> is a
feature supported by the LibXtract library. A complete list of features
may be obtained by sending the external a |help( message:;
#X obj 27 262 xtract~;
#X msg 27 233 help;
#X text 26 298 Other than this help message \, the data sent to the
left inlet should always be a 'signal' (i.e. audio rate). This is the
data from a which a given feature will be extracted.;
#X obj 182 490 xtract~ mean;
#X floatatom 132 586 10 0 0 0 - - -;
#X floatatom 253 523 5 0 0 0 - - -;
#X msg 182 522 list \$1;
#X obj 132 556 xtract~ variance;
#X obj 181 466 phasor~ 0.1;
#X text 39 641 Below are some possible use cases (click to open):;
#X text 26 352 The outlet may be a scalar (control rate) \, or a vector
(audio rate) \, depending on the nature of the feature that is being
extracted.;
#X obj 42 665 f0;
#X obj 83 665 mfcc;
#X text 27 405 Any additional arguments that need to be passed to the
feature extraction function must be provided as a list to the right
inlet \, e.g.;
#X connect 5 0 4 0;
#X connect 7 0 9 0;
#X connect 7 0 10 0;
#X connect 10 0 11 1;
#X connect 11 0 8 0;
#X connect 12 0 7 0;
#X connect 12 0 11 0;