Early detection of COVID-19 plays a vital role in enabling timely treatment and curbing the spread of the virus. This study introduces a novel hybrid deep learning model tailored to identify COVID-19 infections from chest CT scan images, aiming to support healthcare professionals facing overwhelming diagnostic demands. Our approach integrates the strengths of three pre-trained convolutional neural networks namely VGG16, DenseNet121, and MobileNetV2, each known for their robust feature extraction capabilities. These models independently extract deep features from input CT images, capturing both low-level and high-level representations essential for accurate classification. To address potential redundancy and reduce the computational burden, Principal Component Analysis (PCA) is employed for dimensionality reduction. The refined feature vectors from all three models are then concatenated to form a comprehensive feature representation, which is subsequently passed to a Support Vector Classifier (SVC) for final classification. Our hybrid architecture enables the model to leverage the complementary strengths of each CNN while maintaining efficiency. We evaluated our proposed model on a dataset consisting of 2,108 training images and 373 test images, comprising both COVID-positive and non-COVID samples. Comparative analysis with individual CNN models showed that our hybrid model achieved superior performance, reaching an accuracy of 98.93%. It also outperformed standalone models in precision, recall, F1-score, and ROC-AUC, highlighting its potential as a highly reliable and efficient diagnostic aid.
Published in | American Journal of Artificial Intelligence (Volume 9, Issue 1) |
DOI | 10.11648/j.ajai.20250901.14 |
Page(s) | 30-45 |
Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
Copyright |
Copyright © The Author(s), 2025. Published by Science Publishing Group |
COVID-19 Detection, VGG16, DenseNet121, MobileNetV2, Principal Component Analysis (PCA), Support Vector Classifier (SVC), Feature Fusion, Ensemble Model
[1] | Alsaif, A., & Karam, M. (2022). Chest ct vs rt-pcr for the detection of covid-19: systematic review and meta-analysis of comparative studies. Chest, 161(6), A158. |
[2] | Ng M.-Y., Lee E. Y., Yang J., Yang F., Li X., Wang H., Lui M. M.-s., Lo C. S.-Y., Leung B., Khong P.-L. Imaging profile of the covid-19 infection: radiologic findings and literature review. Radiology: Cardiothoracic Imaging. 2020; 2(1) |
[3] | Hemdan E. E.-D., Shouman M. A., Karar M. E. 2020. Covidx-net: a framework of deep learning classifiers to diagnose covid-19 in x-ray images; p. 11055. arXiv preprint arXiv: 2003. |
[4] | Farooq M., Hafeez A. 2020. Covid-resnet: a deep learning framework for screening of covid19 from radiographs; p. 14395. arXiv preprint arXiv: 2003. |
[5] | Li T., Han Z., Wei B., Zheng Y., Hong Y., Cong J. 2020. Robust screening of covid-19 from chest x-ray via discriminative cost-sensitive learning; p. 12592. ArXiv abs/2004. |
[6] | Abbas A., Abdelsamea M., Gaber M. medRxiv; 2020. Classification of covid-19 in chest x-ray images using detrac deep convolutional neural network. Applied Intelligence. 2021. |
[7] | Wang L., Wong A. 2020. Covid-net: a tailored deep convolutional neural network design for detection of covid-19 cases from chest radiography images. arXiv preprint arXiv: 003.09871. |
[8] | Luz E., Silva P. L., Silva R., Silva L., Moreira G., Menotti D. 2020. Towards an effective and efficient deep learning model for covid-19 patterns detection in x-ray images. arXiv: 2004.05717. |
[9] | El Houby, E. M. F. COVID‑19 detection from chest X-ray images using transfer learning. Sci Rep 14, 11639 (2024). |
[10] | Nishio, M., Noguchi, S., Matsuo, H. et al. Automatic classification between COVID-19 pneumonia, non-COVID-19 pneumonia, and the healthy on chest X-ray image: combination of data augmentation methods. Sci Rep 10, 17532 (2020). |
[11] | Minaee, Shervin, Rahele Kafieh, Milan Sonka, Shakib Yazdani, and Ghazaleh Jamalipour Soufi. "Deep-COVID: Predicting COVID-19 from Chest X-ray Images Using Deep Transfer Learning." Medical Image Analysis 65, (2020): 101794. Accessed December 3, 2024. |
[12] | Emin Sahin, M. "Deep Learning-based Approach for Detecting COVID-19 in Chest X-rays." Biomedical Signal Processing and Control 78, (2022): 103977. Accessed December 3, 2024. |
[13] | Panwar, H. et al. Application of deep learning for fast detection of COVID-19 in X-Rays using nCOVnet. Chaos Solitons Fractals 138, 109944 (2020). |
[14] | Nigam, B. et al. COVID-19: Automatic detection from X-ray images by utilizing deep learning methods. Expert Syst. Appl. 176, 114883 (2021). |
[15] | Chow, L. S. et al. Quantitative and qualitative analysis of 18 deep convolutional neural network (CNN) models with transfer learning to diagnose COVID-19 on chest X-ray (CXR) images. SN Comput. Sci. 4(2), 141 (2023). |
[16] | Gour M, Jain S. Uncertainty-aware convolutional neural network for COVID-19 X-ray images classification. Comput Biol Med. 2022; 140: 105047. |
[17] | Loey E-SS, Mirjalili S. Bayesian-based optimized deep learning model to detect COVID-19 patients using chest X-ray image data. Comput Biol Med. 2022; 142: 105213. |
[18] | Apostolopoulos ID, Mpesiana TA. Covid-19: automatic detection from X-ray images utilizing transfer learning with convolutional neural networks. Phys Eng Sci Med. 2020; 43(2): 635–40. |
[19] | Nayak SR, Nayak DR, Sinha U, Arora V, Pachori RB. Application of deep learning techniques for detection of COVID-19 cases using chest X-ray images: a comprehensive study. Biomed Signal Process Control. 2021; 64: 102365. |
[20] | Majeed T, Rashid R, Ali D, Asaad A. Issues associated with deploying CNN transfer learning to detect COVID-19 from chest X-rays. Phys Eng Sci Med. 2020; 43(4): 1289–303. |
[21] | Soares LP, Soares CP. “Automatic detection of COVID-19 cases on X-ray images Using Convolutional Neural Networks,” 2020. [Online]. Available: |
[22] | He, Xuehai, Xingyi Yang, Shanghang Zhang, Jinyu Zhao, Yichen Zhang, Eric Xing, and Pengtao Xie. "Sample-efficient deep learning for COVID-19 diagnosis based on CT scans." medrxiv (2020): 2020-04. |
[23] | Mobiny, Aryan, Pietro Antonio Cicalese, Samira Zare, Pengyu Yuan, Mohammadsajad Abavisani, Carol C. Wu, Jitesh Ahuja, Patricia M. de Groot, and Hien Van Nguyen. "Radiologist-level covid-19 detection using ct scans with detail-oriented capsule networks." arXiv preprint arXiv: 2004. 07407 (2020). |
[24] | Polsinelli, Matteo, Luigi Cinque, and Giuseppe Placidi. "A light CNN for detecting COVID-19 from CT scans of the chest." Pattern recognition letters 140 (2020): 95-100. |
[25] | Amyar, Amine, Romain Modzelewski, Hua Li, and Su Ruan. "Multi-task deep learning based CT imaging analysis for COVID-19 pneumonia: Classification and segmentation." Computers in biology and medicine 126 (2020): 104037. |
[26] | Wang, Shuai, Bo Kang, Jinlu Ma, Xianjun Zeng, Mingming Xiao, Jia Guo, Mengjiao Cai et al. "A deep learning algorithm using CT images to screen for Corona Virus Disease (COVID-19)." European radiology 31 (2021): 6096-6104. |
[27] | Soares, Eduardo, Plamen Angelov, Sarah Biaso, Michele Higa Froes, and Daniel Kanda Abe. "SARS-CoV-2 CT-scan dataset: A large dataset of real patients CT scans for SARS-CoV-2 identification." MedRxiv (2020): 2020-04. |
[28] | Karpurapu, Shanthi, Sravanthy Myneni, Unnati Nettur, Likhit Sagar Gajja, Dave Burke, Tom Stiehm, and Jeffery Payne. "Comprehensive Evaluation and Insights into the Use of Large Language Models in the Automation of Behavior-Driven Development Acceptance Test Formulation." IEEE Access (2024) |
[29] | Nettur, Suresh Babu, Shanthi Karpurapu, Unnati Nettur, and Likhit Sagar Gajja. "Cypress Copilot: Development of an AI Assistant for Boosting Productivity and Transforming Web Application Testing." IEEE Access (2024). |
[30] | Nettur, Suresh B., Shanthi Karpurapu, Unnati Nettur, Likhit S. Gajja, Sravanthy Myneni, Akhil Dusi, and Lalithya Posham. "UltraLightSqueezeNet: A Deep Learning Architecture for Malaria Classification with up to 54x Fewer Trainable Parameters for Resource Constrained Devices." ArXiv, (2025). Accessed January 28, 2025. |
[31] | Nettur, Suresh B., Shanthi Karpurapu, Unnati Nettur, Likhit S. Gajja, Sravanthy Myneni, Akhil Dusi, and Lalithya Posham. "Lightweight Weighted Average Ensemble Model for Pneumonia Detection in Chest X-Ray Images." ArXiv, (2025). Accessed January 28, 2025. |
[32] | Xu, Xiaowei, Xiangao Jiang, Chunlian Ma, Peng Du, Xukun Li, Shuangzhi Lv, Liang Yu et al. "A deep learning system to screen novel coronavirus disease 2019 pneumonia." Engineering 6, no. 10 (2020): 1122-1129. |
[33] | Wang, Zhao, Quande Liu, and Qi Dou. "Contrastive cross-site learning with redesigned net for COVID-19 CT classification." IEEE Journal of Biomedical and Health Informatics 24, no. 10 (2020): 2806-2813. |
[34] | Han, Zhongyi, Benzheng Wei, Yanfei Hong, Tianyang Li, Jinyu Cong, Xue Zhu, Haifeng Wei, and Wei Zhang. "Accurate screening of COVID-19 using attention-based deep 3D multiple instance learning." IEEE transactions on medical imaging 39, no. 8 (2020): 2584-2594. |
[35] | Haryanto, Toto, Heru Suhartanto, Aniati Murni, Kusmardi Kusmardi, Marina Yusoff, and Jasni Mohammad Zain. "SCOV-CNN: A Simple CNN Architecture for COVID-19 Identification Based on the CT Images." JOIV: International Journal on Informatics Visualization 8, no. 1 (2024): 175-182. |
[36] | Rajpoot, Reenu, Mahesh Gour, Sweta Jain, and Vijay Bhaskar Semwal. "Integrated ensemble CNN and explainable AI for COVID-19 diagnosis from CT scan and X-ray images." Scientific Reports 14, no. 1 (2024): 24985. |
[37] | Islam, Md Robiul, and Md Nahiduzzaman. "Complex features extraction with deep learning model for the detection of COVID19 from CT scan images using ensemble based machine learning approach." Expert Systems with Applications 195 (2022): 116554. |
[38] | Kundu, Rohit, Pawan Kumar Singh, Massimiliano Ferrara, Ali Ahmadian, and Ram Sarkar. "ET-NET: an ensemble of transfer learning models for prediction of COVID-19 infection through chest CT-scan images." Multimedia Tools and Applications 81, no. 1 (2022): 31-50. |
[39] | Aversano, Lerina, Mario Luca Bernardi, Marta Cimitile, and Riccardo Pecori. "Deep neural networks ensemble to detect COVID-19 from CT scans." Pattern Recognition 120 (2021): 108135. |
[40] | Shaik, Nagur Shareef, and Teja Krishna Cherukuri. "Transfer learning based novel ensemble classifier for COVID-19 detection from chest CT-scans." Computers in Biology and Medicine 141 (2022): 105127. |
[41] | Maftouni, Maede, Andrew Chung Chee Law, Bo Shen, Zhenyu James Kong Grado, Yangze Zhou, and Niloofar Ayoobi Yazdi. "A robust ensemble-deep learning model for COVID-19 diagnosis based on an integrated CT scan images database." In IIE annual conference. Proceedings, pp. 632-637. Institute of Industrial and Systems Engineers (IISE), 2021. |
[42] | de Jesus Silva, Lúcio Flávio, Omar Andres Carmona Cortes, and João Otávio Bandeira Diniz. "A novel ensemble CNN model for COVID-19 classification in computerized tomography scans." Results in Control and Optimization 11 (2023): 100215. |
[43] |
Kaggle. SARS-CoV-2 CT-Scan Dataset. Available from:
https://www.kaggle.com/plameneduardo/sarscov2-ctscan-dataset (accessed 27 April 2025). |
[44] | M. Sandler, A. Howard, M. Zhu, A. Zhmoginov and L.-C. Chen, "MobileNetV2: Inverted residuals and linear bottlenecks", Proc. IEEE/CVF Conf. Comput. Vis. Pattern Recognit., pp. 4510-4520, Jun. 2018. |
[45] | Dong, Ke, Chengjie Zhou, Yihan Ruan, and Yuzhi Li. "MobileNetV2 model for image classification." In 2020 2nd International Conference on Information Technology and Computer Application (ITCA), pp. 476-480. IEEE, 2020. |
[46] | Gulzar, Yonis. "Fruit image classification model based on MobileNetV2 with deep transfer learning technique." Sustainability 15, no. 3 (2023): 1906. |
[47] | Xiang, Qian, Xiaodan Wang, Rui Li, Guoling Zhang, Jie Lai, and Qingshuang Hu. "Fruit image classification based on Mobilenetv2 with transfer learning technique." In Proceedings of the 3rd international conference on computer science and application engineering, pp. 1-7. 2019. |
[48] | Liu, Jun, and Xuewei Wang. "Early recognition of tomato gray leaf spot disease based on MobileNetv2-YOLOv3 model." Plant Methods 16 (2020): 1-16. |
[49] | Sanjaya, Samuel Ady, and Suryo Adi Rakhmawan. "Face mask detection using MobileNetV2 in the era of COVID-19 pandemic." In 2020 International Conference on Data Analytics for Business and Industry: Way Towards a Sustainable Economy (ICDABI), pp. 1-5. IEEE, 2020. |
[50] | Nagrath, Preeti, Rachna Jain, Agam Madan, Rohan Arora, Piyush Kataria, and Jude Hemanth. "SSDMNV2: A real time DNN-based face mask detection system using single shot multibox detector and MobileNetV2." Sustainable cities and society 66 (2021): 102692. |
[51] | G. Huang, Z. Liu, L. Van Der Maaten and K. Q. Weinberger, "Densely connected convolutional networks", Proc. IEEE Conf. Comput. Vis. Pattern Recognit. (CVPR), pp. 4700-4708, Jul. 2017. |
[52] | Nandhini, S., and K. Ashokkumar. "An automatic plant leaf disease identification using DenseNet-121 architecture with a mutation-based henry gas solubility optimization algorithm." Neural Computing and Applications 34, no. 7 (2022): 5513-5534. |
[53] | H. Amin, A. Darwish, A. E. Hassanien and M. Soliman, "End-to-End Deep Learning Model for Corn Leaf Disease Classification," in IEEE Access, vol. 10, pp. 31103-31115, 2022, |
[54] | Chhabra, Mohit, and Rajneesh Kumar. "A smart healthcare system based on classifier DenseNet 121 model to detect multiple diseases." In Mobile Radio Communications and 5G Networks: Proceedings of Second MRCN 2021, pp. 297-312. Singapore: Springer Nature Singapore, 2022. |
[55] | Zhou, Qi, Wenjie Zhu, Fuchen Li, Mingqing Yuan, Linfeng Zheng, and Xu Liu. "Transfer learning of the ResNet-18 and DenseNet-121 model used to diagnose intracranial hemorrhage in CT scanning." Current Pharmaceutical Design 28, no. 4 (2022): 287-295. |
[56] | Solano-Rojas, Braulio, Ricardo Villalón-Fonseca, and Gabriela Marín-Raventós. "Alzheimer’s disease early detection using a low cost three-dimensional densenet-121 architecture." In The Impact of Digital Technologies on Public Health in Developed and Developing Countries: 18th International Conference, ICOST 2020, Hammamet, Tunisia, June 24–26, 2020, Proceedings 18, pp. 3-15. Springer International Publishing, 2020. |
[57] | Zebari, Nechirvan Asaad, Ahmed AH Alkurdi, Ridwan B. Marqas, and Merdin Shamal Salih. "Enhancing Brain Tumor Classification with Data Augmentation and DenseNet121." Academic Journal of Nawroz University 12, no. 4 (2023): 323-334. |
[58] | K. Simonyan and A. Zisserman, "Very deep convolutional networks for large-scale image recognition", arXiv: 1409. 1556, 2014. |
[59] | Qassim, Hussam, Abhishek Verma, and David Feinzimer. "Compressed residual-VGG16 CNN model for big data places image recognition." In 2018 IEEE 8th annual computing and communication workshop and conference (CCWC), pp. 169-175. IEEE, 2018. |
[60] | Krishnaswamy Rangarajan, Aravind, and Raja Purushothaman. "Disease classification in eggplant using pre-trained VGG16 and MSVM." Scientific reports 10, no. 1 (2020): 2322. |
[61] | Albashish, Dheeb, Rizik Al-Sayyed, Azizi Abdullah, Mohammad Hashem Ryalat, and Nedaa Ahmad Almansour. "Deep CNN model based on VGG16 for breast cancer classification." In 2021 International conference on information technology (ICIT), pp. 805-810. IEEE, 2021. |
[62] | Jiang, Zhi-Peng, Yi-Yang Liu, Zhen-En Shao, and Ko-Wei Huang. "An improved VGG16 model for pneumonia image classification." Applied Sciences 11, no. 23 (2021): 11185. |
[63] | Mascarenhas, Sheldon, and Mukul Agarwal. "A comparison between VGG16, VGG19 and ResNet50 architecture frameworks for Image Classification." In 2021 International conference on disruptive technologies for multi-disciplinary research and applications (CENTCON), vol. 1, pp. 96-99. IEEE, 2021. |
[64] | Wang, Hao. "Garbage recognition and classification system based on convolutional neural network vgg16." In 2020 3rd International Conference on Advanced Electronic Materials, Computers and Software Engineering (AEMCSE), pp. 252-255. IEEE, 2020. |
[65] | Liu, Zhihao, Jingzhu Wu, Longsheng Fu, Yaqoob Majeed, Yali Feng, Rui Li, and Yongjie Cui. "Improved kiwifruit detection using pre-trained VGG16 with RGB and NIR information fusion." IEEE access 8 (2019): 2327-2336. |
[66] | Qu, Zhong, Jing Mei, Ling Liu, and Dong-Yang Zhou. "Crack detection of concrete pavement with cross-entropy loss function and improved VGG16 network model." Ieee Access 8 (2020): 54564-54573. |
[67] | Lin, Min, Qiang Chen, and Shuicheng Yan. "Network In Network." ArXiv, (2013). Accessed December 4, 2024. |
[68] | Srivastava, Nitish, Geoffrey Hinton, Alex Krizhevsky, Ilya Sutskever, and Ruslan Salakhutdinov. "Dropout: a simple way to prevent neural networks from overfitting." The journal of machine learning research 15, no. 1 (2014): 1929-1958. |
[69] | Ioffe, Sergey. "Batch normalization: Accelerating deep network training by reducing internal covariate shift." arXiv preprint arXiv: 1502. 03167 (2015). |
[70] | Santosh, KC, Debasmita GhoshRoy, and Suprim Nakarmi. 2023. "A Systematic Review on Deep Structured Learning for COVID-19 Screening Using Chest CT from 2020 to 2022" Healthcare 11, no. 17: 2388. |
APA Style
Nettur, S. B., Karpurapu, S., Nettur, U., Gajja, L. S., Myneni, S., et al. (2025). A Hybrid Deep Learning CNN Model for Enhanced COVID-19 Detection from Computed Tomography (CT) Scan Images. American Journal of Artificial Intelligence, 9(1), 30-45. https://doi.org/10.11648/j.ajai.20250901.14
ACS Style
Nettur, S. B.; Karpurapu, S.; Nettur, U.; Gajja, L. S.; Myneni, S., et al. A Hybrid Deep Learning CNN Model for Enhanced COVID-19 Detection from Computed Tomography (CT) Scan Images. Am. J. Artif. Intell. 2025, 9(1), 30-45. doi: 10.11648/j.ajai.20250901.14
@article{10.11648/j.ajai.20250901.14, author = {Suresh Babu Nettur and Shanthi Karpurapu and Unnati Nettur and Likhit Sagar Gajja and Sravanthy Myneni and Akhil Dusi and Lalithya Posham}, title = {A Hybrid Deep Learning CNN Model for Enhanced COVID-19 Detection from Computed Tomography (CT) Scan Images }, journal = {American Journal of Artificial Intelligence}, volume = {9}, number = {1}, pages = {30-45}, doi = {10.11648/j.ajai.20250901.14}, url = {https://doi.org/10.11648/j.ajai.20250901.14}, eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajai.20250901.14}, abstract = {Early detection of COVID-19 plays a vital role in enabling timely treatment and curbing the spread of the virus. This study introduces a novel hybrid deep learning model tailored to identify COVID-19 infections from chest CT scan images, aiming to support healthcare professionals facing overwhelming diagnostic demands. Our approach integrates the strengths of three pre-trained convolutional neural networks namely VGG16, DenseNet121, and MobileNetV2, each known for their robust feature extraction capabilities. These models independently extract deep features from input CT images, capturing both low-level and high-level representations essential for accurate classification. To address potential redundancy and reduce the computational burden, Principal Component Analysis (PCA) is employed for dimensionality reduction. The refined feature vectors from all three models are then concatenated to form a comprehensive feature representation, which is subsequently passed to a Support Vector Classifier (SVC) for final classification. Our hybrid architecture enables the model to leverage the complementary strengths of each CNN while maintaining efficiency. We evaluated our proposed model on a dataset consisting of 2,108 training images and 373 test images, comprising both COVID-positive and non-COVID samples. Comparative analysis with individual CNN models showed that our hybrid model achieved superior performance, reaching an accuracy of 98.93%. It also outperformed standalone models in precision, recall, F1-score, and ROC-AUC, highlighting its potential as a highly reliable and efficient diagnostic aid. }, year = {2025} }
TY - JOUR T1 - A Hybrid Deep Learning CNN Model for Enhanced COVID-19 Detection from Computed Tomography (CT) Scan Images AU - Suresh Babu Nettur AU - Shanthi Karpurapu AU - Unnati Nettur AU - Likhit Sagar Gajja AU - Sravanthy Myneni AU - Akhil Dusi AU - Lalithya Posham Y1 - 2025/05/24 PY - 2025 N1 - https://doi.org/10.11648/j.ajai.20250901.14 DO - 10.11648/j.ajai.20250901.14 T2 - American Journal of Artificial Intelligence JF - American Journal of Artificial Intelligence JO - American Journal of Artificial Intelligence SP - 30 EP - 45 PB - Science Publishing Group SN - 2639-9733 UR - https://doi.org/10.11648/j.ajai.20250901.14 AB - Early detection of COVID-19 plays a vital role in enabling timely treatment and curbing the spread of the virus. This study introduces a novel hybrid deep learning model tailored to identify COVID-19 infections from chest CT scan images, aiming to support healthcare professionals facing overwhelming diagnostic demands. Our approach integrates the strengths of three pre-trained convolutional neural networks namely VGG16, DenseNet121, and MobileNetV2, each known for their robust feature extraction capabilities. These models independently extract deep features from input CT images, capturing both low-level and high-level representations essential for accurate classification. To address potential redundancy and reduce the computational burden, Principal Component Analysis (PCA) is employed for dimensionality reduction. The refined feature vectors from all three models are then concatenated to form a comprehensive feature representation, which is subsequently passed to a Support Vector Classifier (SVC) for final classification. Our hybrid architecture enables the model to leverage the complementary strengths of each CNN while maintaining efficiency. We evaluated our proposed model on a dataset consisting of 2,108 training images and 373 test images, comprising both COVID-positive and non-COVID samples. Comparative analysis with individual CNN models showed that our hybrid model achieved superior performance, reaching an accuracy of 98.93%. It also outperformed standalone models in precision, recall, F1-score, and ROC-AUC, highlighting its potential as a highly reliable and efficient diagnostic aid. VL - 9 IS - 1 ER -