Introduction: When AI meets Mozart
"Music is a flowing building." When artificial intelligence begins to understand the mathematical laws between musical notes, music creation is undergoing unprecedented paradigm changes. This article will teach you step by step to build an intelligent composition system, which can not only generate classical piano sketches, but also achieve free conversion of baroque and jazz styles. By practicing LSTM neural networks, style transfer algorithms and audio synthesis technology, you will master the core principles of generative AI and create your own AI musicians by yourself.
1. Technology stack analysis and development environment construction
1.1 Core toolchain
- TensorFlow : Google's open source deep learning framework
- Magenta: TensorFlow extension library designed for art generation
- MIDIUtil: MIDI file processing library
- Flask: Lightweight Web framework (used to build interactive interfaces)
1.2 Environment configuration
# Create a virtual environment
python -m venv ai_composer_env
source ai_composer_env/bin/activate # Linux/Mac
ai_composer_env\Scripts\ # Windows
# Installation dependencies
pip install tensorflow magenta midiutil flask
2. Music data preparation and processing
2.1 MIDI file parsing
from import midi_io
from import melodies_lib
def parse_midi(file_path):
midi_data = midi_io.midi_file_to_note_sequence(file_path)
return melodies_lib.extract_melodies(midi_data)
# Example: Analysis of Beethoven's "To Alice"
melody = parse_midi("beethoven_fur_elise.mid")[0]
2.2 Data preprocessing
- Note encoding: Convert notes to numerical sequences (C4=60, D4=62...)
- Rhythm quantization: Discrete the timeline into 16-minute note units
-
Sequence fill: Use special marks
<PAD>
Unified sequence length
3. LSTM music generation model training
3.1 Model architecture
import tensorflow as tf
from import LSTM, Dense
def build_model(input_shape, num_notes):
model = ([
LSTM(512, return_sequences=True, input_shape=input_shape),
LSTM(512),
Dense(num_notes, activation='softmax')
])
(loss='categorical_crossentropy', optimizer='adam')
return model
3.2 Training Process
- Data loading: Use Magenta's built-in piano MIDI dataset
- Sequence generation: Create input-output pairs of 100 time steps
- Model training:
# Sample training code
model = build_model((100, 128), 128) # Assume 128 notes categories
(X_train, y_train, epochs=50, batch_size=64)
IV. Implementation of style transfer algorithm
4.1 Style feature extraction
- Pitch distribution: Statistics the frequency of occurrence of each sound level
- Rhythm Mode: Calculate the duration distribution of notes
- Harmony direction: Analyze the chord progression rules
4.2 Style conversion network
def style_transfer(content_melody, style_features):
# Style encoding using pre-trained VAE models
content_latent = (content_melody)
style_latent = style_encoder.predict(style_features)
# Mix potential space
mixed_latent = 0.7*content_latent + 0.3*style_latent
return (mixed_latent)
V. Audio synthesis module development
5.1 MIDI generation
from midiutil import MIDIFile
def generate_midi(melody, filename):
track = 0
time = 0
midi = MIDIFile(1)
for note in melody:
pitch =
duration = note.end_time - note.start_time
(track, channel, pitch, time, duration, volume)
time += duration
with open(filename, "wb") as output_file:
(output_file)
5.2 Audio rendering
# Use FluidSynth to convert MIDI audio
fluidsyncth -ni soundfont.sf2 -F -r 44100
6. Construction of interactive web interface
6.1 Backend API
from flask import Flask, request, send_file
app = Flask(__name__)
@('/generate', methods=['POST'])
def generate_music():
style = ['style']
# Call the generated function
midi_data = ai_composer.generate(style)
# Convert to WAV
audio_data = convert_midi_to_wav(midi_data)
return send_file(audio_data, mimetype='audio/wav')
if __name__ == '__main__':
(debug=True)
6.2 Front-end interface
<!-- Simplified HTML interface -->
<div class="container">
<select >
<option value="classical">Classical</option>
<option value="jazz">Jazz</option>
</select>
<button onclick="generateMusic()">Generate music</button>
<audio controls></audio>
</div>
<script>
function generateMusic() {
const style = ('style-selector').value;
fetch('/generate', {
method: 'POST',
headers: {'Content-Type': 'application/json'},
body: ({style})
})
.then(response => ())
.then(blob => {
const audioUrl = (blob);
('audio-player').src = audioUrl;
});
}
</script>
7. System optimization and expansion
7.1 Performance improvement
- useGPU accelerationtrain
- useMixed precision training
- accomplishModel quantizationdeploy
7.2 Functional extension
- Add toMultiple instrument support
- integratedReal-time interactive editing
- DevelopmentEmotional perception generation
Conclusion: The future picture of AI composition
What we are building is not only a music generation tool, but also a new window to AI creativity. When algorithms begin to understand Bach's fugue logic and when neural networks can capture Debussy's impressionism, music creation is entering a new era of human-computer collaboration. This 5,000-word tutorial is just the starting point. I hope you can create more amazing AI music works based on this.
Technical depth tips: Trying to use the Transformer architecture to replace LSTM in model training can significantly improve long-range dependency modeling capabilities; exploring the application of adversarial training (GAN) in music generation can produce more expressive works.