Gang Zhang

Dr. Gang Zhang

Institute of Optics and Electronics, Chinese Academy of Sciences
orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 March 2020 in Symmetry
Verified
Journal Article
Open access
PDF file
SZSanxing Zhang
Sanxing Zhang
ZMZhenhuan Ma
Zhenhuan Ma
GZGang Zhang
Gang Zhang
TLTao Lei
Tao Lei
RZRui Zhang
Rui Zhang
YCYi Cui
Yi Cui
Semantic image segmentation, as one of the most popular tasks in computer vision, has been widely used in autonomous driving, robotics and other fields. Currently, deep convolutional neural networks (DCNNs) are driving major advances in semantic segmentation due to their powerful feature representation. However, DCNNs extract high-level feature representations by strided convolution, which makes it impossible to segment foreground objects precisely, especially when locating object boundaries. This paper presents a novel semantic segmentation algorithm with DeepLab v3+ and super-pixel segmentation algorithm-quick shift. DeepLab v3+ is employed to generate a class-indexed score map for the input image. Quick shift is applied to segment the input image into superpixels. Outputs of them are then fed into a class voting module to refine the semantic segmentation results. Extensive experiments on proposed semantic image segmentation are performed over PASCAL VOC 2012 dataset, and results that the proposed method can provide a more efficient solution.

26 February 2025 in IEEE Geoscience and Remote Sensing Letters
Verified
Journal Article
Closed access
XZXiangyue Zheng
Xiangyue Zheng
JBJingxin Bi
Jingxin Bi
KLKeda Li
Keda Li
GZGang Zhang
Gang Zhang
PJPing Jiang
Ping Jiang
Remote sensing image object detection has advanced significantly, yet small object detection remains challenging due to their limited size and varying scales. Furthermore, real-world deployment often requires algorithms optimized for fewer parameters and faster inference. To address these issues, we propose SMN-YOLO, a lightweight small object detector based on YOLOv8n. Our approach introduces spatial-channel decoupling downsampling to reduce model size while retaining crucial downsampling information. We also present LEFPN, a lightweight multi-scale feature fusion network incorporating Coordinate Attention to capture spatial location cues, enhancing small object detection. Additionally, a multi-scale feature attention module further strengthens feature representation. To improve accuracy, we integrate N-CIoU bounding box regression loss, which minimizes the impact of positional changes on IoU, helping the model focus on low IoU objects. Experimental results on the VEDAI and AI-TOD datasets show that SMN-YOLO outperforms baseline models with a 3.2% and 2.9% improvement in mAP@0.5, respectively, while significantly reducing parameters and only slightly increasing inference time. The proposed model achieves a strong balance between performance and complexity, surpassing several leading detection models.

17 February 2025 in Remote Sensing
Verified
Journal Article
Open access
PDF file
京毕京鑫 毕
京鑫 毕
KLKeda Li
Keda Li
XZXiangyue Zheng
Xiangyue Zheng
GZGang Zhang
Gang Zhang
TLTao Lei
Tao Lei
Target detection in UAV images is of great significance in fields such as traffic safety, emergency rescue, and environmental monitoring. However, images captured by UAVs usually have multi-scale features, complex backgrounds, uneven illumination, and low target resolution, which makes target detection in UAV images very challenging. To tackle these challenges, this paper introduces SPDC-YOLO, a novel model built upon YOLOv8. In the backbone, the model eliminates the last C2f module and the final downsampling module, thus avoiding the loss of small target features. In the neck, this paper proposes a novel feature pyramid, SPC-FPN, which employs the SBA (Selective Boundary Aggregation) module to fuse features from two distinct scales. In the head, the P5 detection head is eliminated, and a new detection head, Dyhead-DCNv4, is proposed, replacing DCNv2 in the original Dyhead with DCNv4 and utilizing three attention mechanisms for dynamic feature weighting. In addition, the model uses the CGB (Context Guided Block) module for downsampling, which can learn and fuse local features with surrounding contextual information, and the PPA (Parallelized Patch-Aware Attention) module replacing the original C2f module to further improve feature expression capability. Finally, SPDC-YOLO adopts EIoU as the loss function to optimize target localization accuracy. On the public dataset VisDrone2019, the experimental results show that SPDC-YOLO improves mAP50 by 3.4% compared to YOLOv8n while reducing the parameters count by 1.03 M. Compared with other related methods, SPDC-YOLO demonstrates better performance.

23 November 2024 in Remote Sensing
Verified
Journal Article
Open access
PDF file
XZXiangyue Zheng
Xiangyue Zheng
YQYijuan Qiu
Yijuan Qiu
GZGang Zhang
Gang Zhang
TLTao Lei
Tao Lei
PJPing Jiang
Ping Jiang
Improving the detection of small objects in remote sensing is essential for its extensive use in various applications. The diminutive size of these objects, coupled with the complex backgrounds in remote sensing images, complicates the detection process. Moreover, operations like downsampling during feature extraction can cause a significant loss of spatial information for small objects, adversely affecting detection accuracy. To tackle these issues, we propose ESL-YOLO, which incorporates feature enhancement, fusion, and a local attention pyramid. This model includes: (1) an innovative plug-and-play feature enhancement module that incorporates multi-scale local contextual information to bolster detection performance for small objects; (2) a spatial-context-guided multi-scale feature fusion framework that enables effective integration of shallow features, thereby minimizing spatial information loss; and (3) a local attention pyramid module aimed at mitigating background noise while highlighting small object characteristics. Evaluations on the publicly accessible remote sensing datasets AI-TOD and DOTAv1.5 indicate that ESL-YOLO significantly surpasses other contemporary object detection frameworks. In particular, ESL-YOLO enhances mean average precision mAP by 10% and 1.1% on the AI-TOD and DOTAv1.5 datasets, respectively, compared to YOLOv8s. This model is particularly adept at small object detection in remote sensing imagery and holds significant potential for practical applications.

24 July 2020 in Remote Sensing
Verified
Journal Article
Open access
PDF file
RZRui Zhang
Rui Zhang
ZCZhenghao Chen
Zhenghao Chen
SZSanxing Zhang
Sanxing Zhang
FSFei Song
Fei Song
GZGang Zhang
Gang Zhang
TLTao Lei
Tao Lei
The widespread applications of remote sensing image scene classification-based Convolutional Neural Networks (CNNs) are severely affected by the lack of large-scale datasets with clean annotations. Data crawled from the Internet or other sources allows for the most rapid expansion of existing datasets at a low-cost. However, directly training on such an expanded dataset can lead to network overfitting to noisy labels. Traditional methods typically divide this noisy dataset into multiple parts. Each part fine-tunes the network separately to improve performance further. These approaches are inefficient and sometimes even hurt performance. To address these problems, this study proposes a novel noisy label distillation method (NLD) based on the end-to-end teacher-student framework. First, unlike general knowledge distillation methods, NLD does not require pre-training on clean or noisy data. Second, NLD effectively distills knowledge from labels across a full range of noise levels for better performance. In addition, NLD can benefit from a fully clean dataset as a model distillation method to improve the student classifier’s performance. NLD is evaluated on three remote sensing image datasets, including UC Merced Land-use, NWPU-RESISC45, AID, in which a variety of noise patterns and noise amounts are injected. Experimental results show that NLD outperforms widely used directly fine-tuning methods and remote sensing pseudo-labeling methods.

19 February 2020 in IEEE Access
Verified
Journal Article
Open access
ZCZhenghao Chen
Zhenghao Chen
RZRui Zhang
Rui Zhang
GZGang Zhang
Gang Zhang
ZMZhenhuan Ma
Zhenhuan Ma
TLTao Lei
Tao Lei
The capability to understand visual scenes with limited labeled data has been widely concerned in the field of computer vision. Although semi-supervised learning for image classification has been extensively studied in some cases, semantic segmentation with limited data has only recently gained attention. In this work, we follow the standard semi-supervised segmentation pipeline for image classification and propose a two-branch network that can encode strong and pseudo label spaces respectively, extracting reliable supervision information from pseudo-labels to assist in training network with strong labels. Our method outperforms previous semi-supervised methods with limited annotation cost. On standard benchmark PASCAL VOC 2012 for semi-supervised semantic segmentation, the proposed approach gains fresh state-of-the-art performance.