PROJECT / 04Audio ML · Feature fusion

Classifying bird species from sound

Different acoustic representations reveal different structure; the model becomes stronger when each receives an appropriate processing branch.

Role
Neural-network design and evaluation
Context
Bird-species audio classification
Period
Academic project
INTERACTIVE EVIDENCE

Explore the multi-branch model.

A multi-branch classifier combining Mel, MFCC, and engineered acoustic features for imbalanced bird-species recognition.

MODEL ARCHITECTURE / SELECT AN INPUT BRANCH Verified tensor shapes
FUSIONConcatenatespecialised features
CLASSIFIERFeed-forward networkseven species outputs
Macro-F1 evaluation
SELECTED BRANCH / 2D CNN

Mel

3 × 100 × 60

Three Mel representations retain time-frequency energy patterns. Each recording contributes 100 aligned time steps to this image-like branch.The heat map is an actual normalised 60-feature window from the executed notebook.

WHY MACRO-F1

Every species gets equal weight.

Macro-F1 calculates a score per class before averaging, so frequent species cannot hide weak performance on rarer classes.

Recorded MNN training and validation macro-F1 curves
THE QUESTION

Classify bird species from recordings represented as 100 time steps and hundreds of acoustic features, while class imbalance makes raw accuracy misleading.

HOW I APPROACHED IT
  1. 01

    Explored feed-forward, convolutional, recurrent, and multi-input neural architectures.

  2. 02

    Separated three Mel maps, nine MFCC maps, and 55 engineered features into specialized convolutional branches before fusion.

  3. 03

    Used macro-averaged F1 so each species contributes equally to evaluation regardless of frequency.

Sequence100 time steps
RepresentationsMel · MFCC · 55 features
Primary metricMacro-F1
BOUNDARY / LIMITATION

The repository does not retain a distributable audio sample and runnable trained model, so this page explains the verified feature tensors and recorded evaluation without simulating a live prediction.

TOOLS & METHODS
  • PyTorch
  • Python
  • CNN
  • MFCC
  • Mel features
  • Macro-F1
Inspect the source repository