Well, the code looks OK to me at first glance -- although I obviously don't know what aae->getBuffers() will return -- hopefully, the current processing block.
Yes actually it's the buffer (jack_default_audio_sample_t) from the jack process.
When you say "the first two values keep increasing over time", do you mean the first two values in each returned column? i.e. features.values and features.values ?
If so, I can't suggest any reason for that -- perhaps some example output might make things clearer?
Ok if i don't play any sound (i.e the buffer is empty), the values are 0 0 and they don't change.
When some changes occur in the buffer (a sound is played), the values are really strange at first (45.0 / 345.0 / 11.0)
then they go back to a very little value when the sound stops and start increasing if i don't play any sound :
Any ideas ?
Thanks for your answer