Improving CNN-based brain tumor classification via differential learning rate and data augmentation strategies
Abstract
Diagnosing brain tumors accurately at an early stage plays an important role in treatment planning and patient survival. Since manual interpretation of medical images is time-consuming and depends heavily on expert experience, automated methods have become increasingly valuable. This study evaluates five transfer learning-based convolutional neural network models, namely DenseNet121, EfficientNetB0, InceptionV3, MobileNetV2, and ResNet50, for multi-class brain tumor classification. To improve classification performance, several data augmentation techniques, including brightness and contrast adjustment, blurring, flipping, and rotation, were applied together with a differential learning rate strategy. This strategy allowed the lower layers of the pretrained networks to preserve general visual representations, while the upper layers adapted more effectively to tumor-specific patterns. The results show that this training approach improved all evaluation metrics compared with fixed learning rate training. EfficientNetB0 achieved the highest performance, with 98.78% accuracy and an F1-score of 0.9878.
Keywords
Ethical Statement
Authors declares that this study complies with research and publication ethic.
Thanks
The authors would like to thank the reviewers and editorial boards of the International Journal of Pure and Applied Sciences.
References
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Details
Primary Language
English
Subjects
Image Processing
Journal Section
Research Article
Publication Date
June 22, 2026
Submission Date
April 3, 2026
Acceptance Date
May 27, 2026
Published in Issue
Year 2026 Volume: 12 Number: 1
APA
Akboyraz, Ö., & Kızıloluk, S. (2026). Improving CNN-based brain tumor classification via differential learning rate and data augmentation strategies. International Journal of Pure and Applied Sciences, 12(1), 352-370. https://doi.org/10.29132/ijpas.1922851
AMA
1.Akboyraz Ö, Kızıloluk S. Improving CNN-based brain tumor classification via differential learning rate and data augmentation strategies. International Journal of Pure and Applied Sciences. 2026;12(1):352-370. doi:10.29132/ijpas.1922851
Chicago
Akboyraz, Özlem, and Soner Kızıloluk. 2026. “Improving CNN-Based Brain Tumor Classification via Differential Learning Rate and Data Augmentation Strategies”. International Journal of Pure and Applied Sciences 12 (1): 352-70. https://doi.org/10.29132/ijpas.1922851.
EndNote
Akboyraz Ö, Kızıloluk S (June 1, 2026) Improving CNN-based brain tumor classification via differential learning rate and data augmentation strategies. International Journal of Pure and Applied Sciences 12 1 352–370.
IEEE
[1]Ö. Akboyraz and S. Kızıloluk, “Improving CNN-based brain tumor classification via differential learning rate and data augmentation strategies”, International Journal of Pure and Applied Sciences, vol. 12, no. 1, pp. 352–370, June 2026, doi: 10.29132/ijpas.1922851.
ISNAD
Akboyraz, Özlem - Kızıloluk, Soner. “Improving CNN-Based Brain Tumor Classification via Differential Learning Rate and Data Augmentation Strategies”. International Journal of Pure and Applied Sciences 12/1 (June 1, 2026): 352-370. https://doi.org/10.29132/ijpas.1922851.
JAMA
1.Akboyraz Ö, Kızıloluk S. Improving CNN-based brain tumor classification via differential learning rate and data augmentation strategies. International Journal of Pure and Applied Sciences. 2026;12:352–370.
MLA
Akboyraz, Özlem, and Soner Kızıloluk. “Improving CNN-Based Brain Tumor Classification via Differential Learning Rate and Data Augmentation Strategies”. International Journal of Pure and Applied Sciences, vol. 12, no. 1, June 2026, pp. 352-70, doi:10.29132/ijpas.1922851.
Vancouver
1.Özlem Akboyraz, Soner Kızıloluk. Improving CNN-based brain tumor classification via differential learning rate and data augmentation strategies. International Journal of Pure and Applied Sciences. 2026 Jun. 1;12(1):352-70. doi:10.29132/ijpas.1922851