EfficientLEAF: A Faster LEarnable Audio Frontend of Questionable Use

12 Jul 2022  ·  Jan Schlüter, Gerald Gutenbrunner ·

In audio classification, differentiable auditory filterbanks with few parameters cover the middle ground between hard-coded spectrograms and raw audio. LEAF (arXiv:2101.08596), a Gabor-based filterbank combined with Per-Channel Energy Normalization (PCEN), has shown promising results, but is computationally expensive. With inhomogeneous convolution kernel sizes and strides, and by replacing PCEN with better parallelizable operations, we can reach similar results more efficiently. In experiments on six audio classification tasks, our frontend matches the accuracy of LEAF at 3% of the cost, but both fail to consistently outperform a fixed mel filterbank. The quest for learnable audio frontends is not solved.

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Task Dataset Model Metric Name Metric Value Global Rank Result Benchmark
Audio Classification BirdCLEF 2021 melspect Accuracy 39.9 # 4
Audio Classification BirdCLEF 2021 LEAF Accuracy 42.3 # 3
Audio Classification BirdCLEF 2021 EfficientLEAF Accuracy 42.9 # 2
Audio Classification BirdCLEF 2021 EfficientLEAF (8s) Accuracy 72.2 # 1
Audio Classification CREMA-D LEAF Accuracy 50.2 # 3
Audio Classification CREMA-D melspect Accuracy 58.8 # 2
Audio Classification CREMA-D EfficientLEAF Accuracy 60.2 # 1
Pitch Classification NSynth melspect Accuracy 91.9 # 3
Instrument Recognition NSynth melspect Accuracy 72.1 # 1
Instrument Recognition NSynth LEAF Accuracy 69.2 # 3
Pitch Classification NSynth EfficientLEAF Accuracy 92.4 # 1
Instrument Recognition NSynth EfficientLEAF Accuracy 71.7 # 2
Pitch Classification NSynth LEAF Accuracy 92.2 # 2
Audio Classification Speech Commands LEAF Accuracy 95.1 # 5
Audio Classification Speech Commands melspect Accuracy 95.1 # 5
Audio Classification Speech Commands EfficientLEAF Accuracy 95.2 # 4
Spoken language identification VoxForge LEAF Accuracy 91.5 # 1
Spoken language identification VoxForge melspect Accuracy 85.6 # 3
Spoken language identification VoxForge EfficientLEAF Accuracy 86.6 # 2

Methods