Locating the array where MFCC features are stored in the generated C++ code for further transmission

I am working on a project where I need to split the MFCC feature extraction from the neural network classification. The MFCC processing is done on an ESP32S3, and I need to send the extracted features over Wi-Fi to a Raspberry Pi for further classification using a neural network. I have generated C++ code with Edge Impulse, but I am having trouble identifying where the MFCC features or spectrogram are stored. Could you guide me on how to locate the array holding this data and best practices for transmitting it over Wi-Fi?

Hello @matgamen,

If you want to output the extracted features, in your res = run_classifier(&signal, &result, false); function, you can set the last argument to true. It will enable the debug and you will be able to see the results.

Where the MFCC extraction is located: Search for the ei_run_dsp.h in the edge-impulse-sdk/classifier directory.

Inside, you will see an extract_mfcc_features function that will populate the matrix_t *output_matrix.

I hope this help.

Best,

Louis

1 Like