Music Auto-Tagger

Music auto-tagger using keras

WARNING! Alternatives available

..because MusicTaggerCNN and MusicTaggerCRNN is based on an old (and a bit incorrect) implementation of Batch Normalization of old Keras (thanks god it worked anyway), it's quite tricky to fix.

Keras Versions

The prerequisite -- READ IT!

"image_dim_ordering": "th",

Files (1)

For MusicTaggerCNN and MusicTaggerCRNN.

Files (2)

For compact_cnn

Structures

Left: compact_cnn CNN, music_tager_cnn. Right: music_tagger_crnn alt text

MusicTaggerCNN

MusicTaggerCRNN

How was it trained?

['rock', 'pop', 'alternative', 'indie', 'electronic', 'female vocalists', 
'dance', '00s', 'alternative rock', 'jazz', 'beautiful', 'metal', 
'chillout', 'male vocalists', 'classic rock', 'soul', 'indie rock',
'Mellow', 'electronica', '80s', 'folk', '90s', 'chill', 'instrumental',
'punk', 'oldies', 'blues', 'hard rock', 'ambient', 'acoustic', 'experimental',
'female vocalist', 'guitar', 'Hip-Hop', '70s', 'party', 'country', 'easy listening',
'sexy', 'catchy', 'funk', 'electro' ,'heavy metal', 'Progressive rock',
'60s', 'rnb', 'indie pop', 'sad', 'House', 'happy']

Which is the better predictor?

Therefore, if you just wanna use the pre-trained weights, use MusicTaggerCNN. If you wanna train by yourself, it's up to you. I would use MusicTaggerCRNN after downsizing it to, like, 0.2M parameters (then the training time would be similar to MusicTaggerCNN) in general. To reduce the size, change number of feature maps of convolution layers.

Which is the better feature extractor?

By setting include_top=False, you can get 256-dim (MusicTaggerCNN) or 32-dim (MusicTaggerCRNN) feature representation.

In general, I would recommend to use MusicTaggerCRNN and 32-dim feature as for predicting 50 tags, 256 features actually sound bit too large. I haven't looked into 256-dim feature but only 32-dim features. I thought of using PCA to reduce the dimension more, but ended up not applying it because mean(abs(recovered - original) / original) are .12 (dim: 32->16), .05 (dim: 32->24) - which don't seem good enough.

Probably the 256-dim features are redundant (which then you can reduce them down effectively with PCA), or they just include more information than 32-dim ones (e.g., features in different hierarchical levels). If the dimension size would not matter, it's worth choosing 256-dim ones.

Usage

$ python example_tagging.py
$ python example_feat_extract.py

Result

theano, MusicTaggerCRNN

data/bensound-cute.mp3
[('jazz', '0.444'), ('instrumental', '0.151'), ('folk', '0.103'), ('Hip-Hop', '0.103'), ('ambient', '0.077')]
[('guitar', '0.068'), ('rock', '0.058'), ('acoustic', '0.054'), ('experimental', '0.051'), ('electronic', '0.042')]

data/bensound-actionable.mp3
[('jazz', '0.416'), ('instrumental', '0.181'), ('Hip-Hop', '0.085'), ('folk', '0.085'), ('rock', '0.081')]
[('ambient', '0.068'), ('guitar', '0.062'), ('Progressive rock', '0.048'), ('experimental', '0.046'), ('acoustic', '0.046')]

data/bensound-dubstep.mp3
[('Hip-Hop', '0.245'), ('rock', '0.183'), ('alternative', '0.081'), ('electronic', '0.076'), ('alternative rock', '0.053')]
[('metal', '0.051'), ('indie', '0.028'), ('instrumental', '0.027'), ('electronica', '0.024'), ('hard rock', '0.023')]

data/bensound-thejazzpiano.mp3
[('jazz', '0.299'), ('instrumental', '0.174'), ('electronic', '0.089'), ('ambient', '0.061'), ('chillout', '0.052')]
[('rock', '0.044'), ('guitar', '0.044'), ('funk', '0.033'), ('chill', '0.032'), ('Progressive rock', '0.029')]

And...

Reproduce the experiment

Credits