|
ShodhKosh: Journal of Visual and Performing ArtsISSN (Online): 2582-7472
GANs for Musical Style Transfer and Learning Syed Fahar Ali
1 1 Associate
Professor, School of Journalism, and Mass Communication, Noida International, University,
203201, India 2 Associate
Professor, Department of Electrical and Electronics Engineering, Arka Jain
University, Jamshedpur, Jharkhand, India 3 Professor, Department of Computer science and Engineering, Faculty of
Engineering and Technology, Parul institute of Technology, Parul University,
Vadodara, Gujarat, India 4 Centre of Research Impact and Outcome, Chitkara University, Rajpura-
140417, Punjab, India 5 Professor and Head, Department of Information Science and Engineering,
JAIN (Deemed-to-be University), Bengaluru, Karnataka, India 6 Department of Mechanical Engineering Vishwakarma Institute of
Technology, Pune, Maharashtra, 411037, India
1. INTRODUCTION Music as an art of all
humankind, has encompassed complicated emotive, cultural, and structural
patterns which have appealed to the curiosity of the scientist, artist, and
technologist. Due to the introduction of artificial intelligence (AI) and deep
learning, automatic creation and transformation of musical content have become
an active research topic. Generative Adversarial Networks (GANs) are one of the
many possible computational methods that have proven to have exceptional
abilities to create, translate, and stylize audio information. GANs, firstly,
were suggested by Goodfellow et al. (2014) and comprise a discriminator and a
generator that act in opposite directions to create realistic results, which
resemble the distribution of natural data. Their achievements in the visual
task of image translation, super-resolution, and style transfer prompted
researchers to investigate similar tasks in the auditory and musical fields.
The term musical style transfer is used to describe the act of moving a musical
composition of one style into another, e.g. turning a classical piano
composition into a jazz improvisation or an electronic copy of an acoustic one
and so forth, without losing the underlying melodic and rhythmic content.
Earlier studies also attempted to use traditional methods that were either
rule-based systems, Hidden Markov Models (HMMs), or Recurrent Neural Networks
(RNNs), but frequently either lost harmonic consistency or rhythmic naturalness
Chen et al. (2024). Variational Autoencoders (VAEs) enhanced those with
learning the latent representations of musical sequences, but did not generate
high-quality and stylistically accurate audio. Instead, GANs have
the ability to learn non-linear mappings and refine them adversarially to have even greater perceptual realism and
stylistic consistency. Recent studies have seen
the adjustment of CycleGANs and Conditional GANs (cGANs) to music style transfer especially in tasks where
paired samples are not available. CycleGANs, which
provide a cycle-consistency between input and output space, make it possible to
learn unpairedly the style to swap, say, pop and
classical music. The use of conditional GANs, in its turn, adds overt
conditioning variables, like tempo, key, or instrument type, to the generation
process Yuan et al. (2022). Such architectures have been effectively generalized
to time-series and spectrogram representations, and have been used to
cross-domain learn using feature-based transformations, as opposed to
note-level symbolic modeling. The significant
difficulty of using GANs to music is the representation and processing of audio
signals. As a contrast to images, music has highly temporal dependencies and
hierarchies; it has melody, harmony, rhythm and timbre, all developing with time.
To overcome this, researchers employ intermediate representations like
Mel-frequency cepstral coefficients (MFCCs) and short-time fourier
transforms (STFTs) and Mel-spectrograms that represent the spectral and
perceptual elements of audio Song et al. (2024). The goal function of the discriminator is then to
adjust to these representations such that it is sensitive to musical texture
and not the amplitude of the waveform. Figure 1 demonstrates the architecture of GAN that allows
learning cross-genre music, transforming it, and synthesizing it. Moreover,
adversarial training is still a challenge to balance; mode collapse or musical
monotony may take place due to unstable convergence. Figure 1 |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Table 1 Summary on Deep Learning Approaches for Musical Style Transfer and Audio Synthesis |
|||
|
Model |
Dataset / Input Type |
Feature Representation |
Objective / Task |
|
GAN (Original) |
Synthetic datasets |
Latent noise vectors |
Adversarial training concept |
|
RNN-LSTM |
MIDI datasets |
Pitch, velocity, duration |
Music generation |
|
VAE (MusicVAE) |
MAESTRO, Lakh MIDI |
Latent embedding |
Style interpolation &
composition |
|
WaveNet Autoencoder |
NSynth Dataset |
Waveform encoding |
Timbre synthesis |
|
CNN + RNN Hybrid |
AudioSpectra |
STFT, MFCC |
Polyphonic music generation |
|
CycleGAN |
GTZAN, MUSDB18 |
Mel-spectrogram |
Unpaired music style
transfer |
|
Conditional GAN |
MagnaTagATune |
Chroma, tempo, key |
Genre-conditioned generation |
|
SpecGAN |
NSynth, UrbanSound8K |
Log-magnitude spectrograms |
Raw audio synthesis |
|
GANSynth |
NSynth |
Phase-aligned waveform |
Pitch & timbre
generation |
|
StyleGAN Audio |
GTZAN |
Mel-spectrogram |
Audio texture transfer |
|
CycleGAN-VC2 |
Voice Conversion Corpus |
Spectral envelopes |
Cross-domain voice style
transfer |
|
Diffusion-GAN Hybrid |
MAESTRO |
Harmonic spectral maps |
High-fidelity music
synthesis |
|
Transformer-GAN |
Lakh & JazzNet |
Symbolic note embeddings |
Long-term composition
transfer |
|
Conditional + CycleGAN |
Mixed (GTZAN, NSynth, MAESTRO) |
MFCC, Mel-spectrogram,
Chroma |
Cross-genre musical style
transfer |
3. Theoretical Framework
3.1. Structure and working principle of GANs
Generative Adversarial
Networks (GANs) are based on the general principle of adversarial learning when
two neural networks, the generator (G) and the discriminator (D) are trained
oppositely. The generator tries to generate the data that are similar to the real ones and the task of the discriminator
is to differentiate between the real and fake data. This structure can be used
in music to induce GANs to learn complicated distributions of audio signals or
symbolic representations including MIDI events Annaki et al.
(2024). The GANs do not explicitly model the probability
densities but are capable of producing a variety of
samples and contextually valid ones, unlike deterministic models. The balance
state of this game is reached when the output of the generator cannot be
differentiated by real data, so that GANs can generate high-fidelity,
stylistically diverse musical generations based on the rhythmic, harmonic and
timbral properties of the target domain Semenoglou et
al. (2023).
3.2. Adaptation of GANs for Time-Series and Waveform Data
Although GANs were
originally used in the context of synthezing static
images, they can also be extended to work with time-series and waveforms, which
makes them useful in audio and music processing. In contrast to images, audio
signal signals have severe temporal dependencies and sequential coherence, and
special architectures are needed to process one-dimensional or two-dimensional
sequential features Li et al. (2021). WaveGAN and SpecGAN models, made alterations to regular convolutional
blocks to take raw waveforms and spectrograms, respectively. Instead of the
traditional two-dimensional convolution, the models use one-dimensional
transposed convolutions in order to capture local
temporal details and maintain phase and amplitude continuity (local temporal
features). Time-series adaptation typically consists of the conversion of
waveforms to spectral representations (e.g. Mel-spectrograms, MFCCs or
constant-Q transforms (CQT)). These attributes are fed into the generator and
discriminator, and allow learning in the frequency domain. Temporal
convolutions and recurrent layers (LSTM or GRU) are also added to represent
long-term rhythmic structures Rakhmatulin et
al. (2024). CycleGANs and conditional
GANs are extensions of this framework, either introducing conditioning signals
(i.e. tempo, pitch or instrument type) or requirements of cyclic consistency
between domains which is needed when task performance (unpaired style transfer)
is being evaluated unconditioned. Figure 2 presents GAN adaptations that are specialized in
their time-series processing and complex waveform data processing. In addition,
the methods of stabilization, i.e., Wasserstein loss, gradient penalty, and
spectral normalization, help to address the problem of mode collapse and
instability common in sequential data.
Figure 2

Figure 2 Illustrating the Adaptation of GANs for Time-Series
and Waveform Data
Through these adaptations,
GANs become capable of synthesizing time-dependent signals with coherent
dynamics, tonal structure, and stylistic fidelity, enabling realistic and
adaptive musical outputs across multiple genres and audio modalities.
3.3. Role of Generator, Discriminator, and Loss Functions in Musical Context
Within the framework of
musical style transfer, all the elements of a GAN have a specific but mutually
supportive role. The generator is an open-ended agent, that is, it learns to
condition latent noise vectors or input features into synthetic musical outputs
that are tonally, rhythmically, and expressively correlated with the target
style. It tries to get the structural information of music melody, harmony,
timbre, and phrasing with the help of convolutational,
recurrent, or attention-based structures. The discriminator on the other hand
is a critic and it compares generated samples with actual music data. It offers
a comment on perceptual quality, coherence, and stylistic consistency and this
directs the generator to get better in the next iteration Mienye et al.
(2024). The determinants of loss are the key to optimizing
this adversarial play. The conventional binary cross-entropy loss motivates the
discriminator to distinguish between the real and the generated data correctly,
whereas the generator aims at reducing this classification. Nevertheless, in
the case of musical data, the Wasserstein loss with gradient penalty (WGAN-GP)
or the least squares loss (LSGAN) is commonly applied to have a stable
convergence point and a gradual gradient, which improves the realism of audio.
Cycle-consistency loss and content preservation loss are as well included in
style transfer to retain the original musical semantics and distort stylistic
elements.
4. Methodology
4.1. Feature extraction and normalization
The initial step of the
musical style transfer process based on GAN is feature extraction and
normalization, which makes sure that unprocessed information about music is
turned into a meaningful and machine-readable form. In contrast to image data,
in music, multidimensional and temporal and spectral data should be encoded in
an appropriate way to include features of rhythm, pitch, timbre, and dynamics.
Representations that are commonly employed are Mel-frequency cepstral
coefficients (MFCCs), Mel-spectrograms, chroma features, spectral contrast, and
zero-crossing rate. Such characteristics are based on short-time Fourier
transform (STFT) analysis that allows to extract both frequency and time
changes that are important in genre and style classification. In the case of
symbolic music data like MIDI files, further information is extracted as note
pitch sequences, velocity, duration, tempo patterns among others. All of these characteristics are the compositional structure
and style of the musical piece as a whole. Upon
extraction of features, the normalization methods are then used to normalize
the data scale and eliminate bias in the training of the model as well as
stability of the numbers. Such techniques as min-max scaling, z-score
normalization and even log compression are used to balance the amplitude
variations and spectral intensity differences.
4.2. GAN architecture design
1) Conditional
GAN
Conditional Generative
Adversarial Networks (cGANs) are based on the
standard framework of GAN but adds conditional variables that are used to
influence the process of data generation. These conditions, expressed in
musical terms, like genre, type of instrument, tempo or mood can be synthesized
more under control and in context sensitive form. The generator G(z|y) is a model that generates a sample that is conditioned
on the random noise z and the attribute y, and the discriminator D(x|y) is a model that determines whether the generated
sample has satisfied the condition.
The optimization objective
of a cGAN is expressed as:
Conditional GAN Objective
Function
![]()
![]()
![]()
Reconstruction-based
Auxiliary Loss
![]()
Within the musical domain, cGANs provide a level of fine control in the style
conditioning process, and such a system can be trained to synthesize a
particular set of rhythm patterns or tonal hues. Through conditioning, cGANs produce more predictable, expressive and style
consistent results than traditional GANs.
2) CycleGAN
Cycle-Consistent Generative
Adversarial Networks (CycleGANs) are unpaired domain translationers and hence they are especially useful in
musical style transfer cases where no parallel datasets exist. Two generators,
G:X Y and F Y X, are trained to learn to map between source and target musical
spaces in this framework, and two discriminators.
CycleGAN Adversarial Loss (Forward Mapping)
![]()
![]()
![]()
Cycle-Consistency Loss
![]()
![]()
![]()
This is so that when an
audio sample is translated to a new style and then translated back to it will
not lose its original melodic and rhythmic character. The cycleGANs
are therefore capable of bidirectional style transfer that allows domain
adaptation across styles (e.g classical vs jazz) and
at the same time preserving musical coherence and perceptual integrity.
5. Experimental Setup
5.1. Hardware and software specifications
GAN-based musical style
transfer can be experimented with a high-performance computing environment that
allows working with large-scale audio data and can extensively train a neural
and perform its tasks. The computer setup in this research will include an
NVIDIA RTX 4090 (24 GB VRAM) graphics card, an Intel Core i9-13900K central
processing unit, 64 GB of DDR5 memory and 2 TB of NVMe
solid state drive to stream and cache data efficiently. The high-resolution
Mel-spectrogram or long waveform sequence have resulted in the deep
convolutional and recurrent layers being fundamental in the method of the
systems to be trained by the use of deep learning,
providing a key benefit in terms of speed and efficiency and the capability to
utilize massive quantities of data. The operating system is a 64-bit Ubuntu
22.04 LTS that has provided the software setup with stability and compatibility
with CUDA drivers. The experiments are based on Python 3.10 as the main
programming language, CUDA 12.1 and cuDNN 8.9 to run
optimally on the computer processing unit. The audio process including
preprocessing and feature extraction are achieved with
the help of Librosa, NumPy, and SciPy, whereas the
main deep learning architecture is implemented with PyTorch
2.1.
5.2. Implementation Environment and Libraries Used
The GAN framework suggested
was implemented in a strong Python-based ecosystem which was optimized to deep
learning and audio signal processing. The PyTorch 2.1
library has been chosen to build a model, train it, and perform calculations
with the help of GPUs because it is flexible with respect to access to dynamic
graphs. The extraction of features, transformation of waveforms, and
calculation of Mel-spectrograms were all done with TorchAudio
and Librosa, which have fundamental pre-processing
capabilities such as resampling, STFT, and normalization. To process data and
enhance it, Pandas and NumPy helped to perform efficient operations with arrays
and organize data in a form of a set. Scaling, normalization and partitioning
of data was done using the Scikit-learn toolkit. The visualization tools were
combined (TensorBoard, Seaborn, and Matplotlib), to
monitor the adversarial loss curves, the balance between the generators and
discriminators, and the development of the spectrograms per epoch. CUDA and cuDNN backends were set up to enable parallelized
operations of the gpus to speed up computation.
Weights & Biases (wandb) was added to keep track
of the experiment and optimize the hyperparameters. The development environment
was configured in Anaconda where the virtual environments were separated to
control dependencies.
6. Applications and Future Scope
6.1. Use in AI-assisted composition and sound design
GAN based systems are
reinventing AI-assisted music creation and sound design by offering intelligent
systems capable of creating stylistically rich and emotionally expressive
music. With adversarial learning, generators are able to
generate realistic timbers, melodic sequences, and harmonic progressions that
can be used to mimic certain genres or composers. This allows musicians to
collaborate with AI, where their creative partners are GANs, which propose
changes, chords, rhymes, etc. To sound designers, GANs have
the ability to create new sounds and tones using spectral properties of
different instruments or environments to create some new hybrid sound.
Furthermore, conditional GANs (cGANs) allow composers
to control generation according to the parameters desired like tempo, mood, or
instrumentation to control and fine-tune generation, increasing control and
artistic accuracy. The created system endorses a symbiotic product development-
creative artists outline conceptual will, whereas GANs produce realizations of
stylistic expression. This kind of integration encourages generative
creativity, shortening the production time, and widening the musical
exploration to the outside limits.
6.2. Integration with Interactive Music Learning Platforms
The implementation of GANs
in interactive music learning applications is a paradigm shift in the
pedagogical perspective of AI as a mentor and a creative assistant. Style
transfer and adaptive generation enable the visual and auditory perception of
how one piece of composition is changed through various stylistic genres like
classical, jazz, rock, or electronic, as well as helping to improve style
literacy and auditory awareness. GANs create musical examples with contextual
relevance based on the skills level and style interest of the learner by
learning on large collections of the human composition. Practically speaking,
this type of systems may provide real-time feedback, propose harmonic
corrections or even hypothesize stylistic embellishments in line with the input
of the student. This forms a feedback learning process, as the AI dynamically
increases or decreases complexity, and offers specific training.
7. Results and Analysis
The GAN-based framework
proposed showed the best result in the musical style transfer across various
musical genres with high perceptual fidelity and style consistency. Fréchet
Audio Distance (FAD), Spectral Convergence (SC), and Mean Opinion Score (MOS)
quantitative evaluation showed improvement relative to baseline models in VAEs
and RNNs. CycleGAN showed a high domain adaptation on
unpaired datasets with melodic and rhythmic integrity with a mean MOS of 4.6/5.
Conditional GANs provided a fine-adjusted control of such attributes as tempo
and timbre.
Table 2
|
Table 2 Quantitative Evaluation of GAN Models for Musical Style Transfer |
||||
|
Evaluation Metric |
Autoencoder |
VAE |
RNN-LSTM |
Conditional GAN |
|
Fréchet Audio Distance
(↓) |
4.82 |
3.91 |
3.64 |
2.41 |
|
Spectral Convergence
(↓) |
0.342 |
0.298 |
0.271 |
0.191 |
|
Mean Opinion Score (MOS,
1–5) (↑) |
3.42 |
3.78 |
4.01 |
4.47 |
|
Genre Consistency (%)
(↑) |
78.3 |
84.7 |
87.2 |
92.8 |
|
Timbre Fidelity Index
(↑) |
80.5 |
82.3 |
86.4 |
91.7 |
A comparative analysis of
different deep learning models on musical style transfer is also provided in Table 2, with the difference between the progressive changes
in adversarial training. Conventional methods like the Autoencoder, VAE and
RNN-LSTM achieve moderate performance in restoring stylistic and tonal
characteristics but have a higher Fréchet Audio Distance (FAD) and Spectral
Convergence (SC) values, which are perceptual and structural constraints to
audio realism.
Figure 3

Figure 3 Trend Comparison of Model Performance Across Audio
Quality Metrics
Figure 3 presents the trends of comparative performance of
several audio quality evaluation metrics. The FAD and SC of 4.82 and 0.342 of
the Autoencoder indicate a rather weak capability to preserve high-level
harmonic coherence and the VAE a little more effectively recreates features
with more smooth latent representations. The RNN-LSTM has a stronger temporal
dependency model, in terms of higher MOS (4.01) and genre consistency (87.2%),
but it has a poor timbral richness and variation. Figure 4 presents the trends of multi-metric evaluation
between performances of different audio generation models.
Figure 4

Figure 4 Evaluation of Audio Generation Models Using
Multi-Metric Analysis
Conversely, the Conditional
GAN presents the most promising overall results in all measures since it has an
FAD of 2.41, SC of 0.191 and a high Mean Opinion Score of 4.47. These advances
verify the higher capacity of GAN to learn intricate distributions, retain
timbral elements (91.7%), and stylistic wholeness (92.8%) over transformations.
8. Conclusion
This study proves the
importance of Generative Adversarial Networks (GANs) as a potent platform of
musical style transfer and learning to close the divide between computational
creativity and human art. The study shows that adversarial learning can be successfully
used to learn complicated temporal and spectral correlations found in musical
pieces through systematic trial and error using Conditional GANs and CycleGANs. The findings validate that GANs are better than
the more traditional deep learning models because they produce musically
coherent, stylistically faithful, and perceptually realistic outputs in a wide
variety of genres. Mel-spectrograms, MFCCs and chroma-based representations
were used as feature engineering which allowed the model to learn complex
harmonic, rhythmic, and timbral ones. Cycle-consistency and
content-preservation losses were used in adversarial training to find a harmony
between musical identity and fidelity to transformation. The architecture that
was implemented had a stable convergence, a minimized mode collapse, and
outputs that are close to human aesthetic perception. Most importantly, this
framework has important implications on AI-assisted composition, interactive
music pedagogy, and real-time performance adaptation. It enables composer and
students to experiment with genre re-invention, timbre variation and expressive
re-interpretation in a manner that stretches the creative frontiers.
CONFLICT OF INTERESTS
None.
ACKNOWLEDGMENTS
None.
REFERENCES
Annaki, I., Rahmoune, M., and Bourhaleb, M. (2024). Overview of Data
Augmentation Techniques in Time Series Analysis. International Journal of
Advanced Computer Science and Applications, 15, 1201–1211. https://doi.org/10.14569/IJACSA.2024.01501118
Chen, J., Teo, T. H., Kok, C. L., and Koh, Y. Y. (2024). A Novel
Single-Word Speech Recognition on Embedded Systems Using a Convolution Neural
Network with Improved Out-of-Distribution Detection. Electronics, 13, 530. https://doi.org/10.3390/electronics13030530
Chen, S., Kalanat, N., Xie, Y., Li, S., Zwart, J. A., Sadler, J. M.,
Appling, A. P., Oliver, S. K., Read, J. S., and Jia, X. (2023). Physics-Guided
Machine Learning from Simulated Data with Different Physical Parameters.
Knowledge and Information Systems, 65, 3223–3250. https://doi.org/10.1007/s10115-023-01864-z
Hazra,
D., and Byun, Y. C. (2020). SynSigGAN: Generative Adversarial Networks for
Synthetic Biomedical Signal Generation. Biology, 9, 441. https://doi.org/10.3390/biology9120441
Huang, F., and Deng, Y. (2023). TCGAN:
Convolutional Generative Adversarial Network for Time Series Classification and
Clustering. Neural Networks, 165, 868–883. https://doi.org/10.1016/j.neunet.2023.06.033
Lan, J., Zhou, Y., Guo, Q., and Sun, H. (2024). Data Augmentation
for Data-Driven Methods in Power System Operation: A Novel Framework Using
Improved GAN and Transfer Learning. IEEE Transactions on Power Systems, 39,
6399–6411. https://doi.org/10.1109/TPWRS.2024.3364166
Li, Z., Liu, F., Yang, W., Peng, S., and Zhou, J. (2021). A Survey of
Convolutional Neural Networks: Analysis, Applications, and Prospects. IEEE
Transactions on Neural Networks and Learning Systems, 33, 6999–7019. https://doi.org/10.1109/TNNLS.2021.3084827
Mienye,
I. D., Swart, T. G., and Obaido, G. (2024). Recurrent Neural Networks:
A Comprehensive Review of Architectures, Variants, and Applications.
Information, 15, 517. https://doi.org/10.3390/info15090517
Rakhmatulin, I.,
Dao, M. S., Nassibi, A., and Mandic, D. (2024). Exploring Convolutional
Neural Network Architectures for EEG Feature Extraction. Sensors, 24, 877. https://doi.org/10.3390/s24030877
Sajeeda, A., and Hossain, B. M. (2022). Exploring
Generative Adversarial Networks and Adversarial Training. International Journal
of Cognitive Computing in Engineering, 3, 78–89. https://doi.org/10.1016/j.ijcce.2022.03.002
Semenoglou, A. A., Spiliotis, E., and
Assimakopoulos, V. (2023). Data Augmentation for Univariate Time Series
Forecasting with Neural Networks. Pattern Recognition, 134, 109132. https://doi.org/10.1016/j.patcog.2022.109132
Song,
X., Xiong, J., Wang, M., Mei, Q., and Lin, X. (2024). Combined Data
Augmentation on EANN to Identify Indoor Anomalous Sound Event. Applied
Sciences, 14, 1327. https://doi.org/10.3390/app14041327
Wen,
Q., Sun, L., Yang, F., Song, X., Gao, J., Wang, X., and Xu, H. (2020). Time Series Data
Augmentation for Deep Learning: A Survey. arXiv. https://doi.org/10.24963/ijcai.2021/631
Yang, S., Guo, S., Zhao, J., and Shen, F. (2024). Investigating the
Effectiveness of Data Augmentation from Similarity and Diversity: An Empirical
Study. Pattern Recognition, 148, 110204. https://doi.org/10.1016/j.patcog.2023.110204
Yuan, R., Wang, B., Sun, Y., Song, X., and Watada, J. (2022). Conditional
Style-Based Generative Adversarial Networks for Renewable Scenario Generation.
IEEE Transactions on Power Systems, 38, 1281–1296. https://doi.org/10.1109/TPWRS.2022.3170992
|
|
This work is licensed under a: Creative Commons Attribution 4.0 International License
© ShodhKosh 2024. All Rights Reserved.