Recently, deep neural networks (DNNs) have emerged as the leading approach for low-light image enhancement (LLIE). However, training these models generally requires large-scale paired datasets, which are challenging to obtain due to the labor-intensive and time-consuming nature of real-world data collection. To alleviate this issue, synthetic data are often combined with real-captured data for training. However, most existing low-light image synthesis methods are simply performed in the sRGB domain using Gamma correction or manual adjustments via Lightroom, which fail to incorporate the physical imaging prior through the image signal processing (ISP) pipeline and thus result in limited dataset size and degradation space. Consequently, LLIE methods trained on such data often exhibit some drawbacks in the results, such as inaccurate white balance and abnormal enhancement artifacts, which limit their practicality and generalizability. In this paper, we propose a practical low-light image synthesis pipeline capable of generating unlimited paired training data. Our pipeline starts with a reverse ISP model that converts sRGB images back to the unprocessed RAW domain, where we then simulate low-light degradation, noise degradation, and white balance adjustments. Finally, the degraded RAW images are processed through a forward ISP model to produce low-light sRGB images. The pipeline further employs multiple tone mapping curves and color correction matrices (CCMs) to expand the degradation space. Hence, trained with our proposed synthetic data, existing state-of-the-art (SOTA) LLIE deep models are expected to improve their performance. Extensive experiments across various datasets demonstrate that our synthetic data can indeed effectively enhance existing LLIE deep models, improving both their practicality and generalizability.

Deep learning-based medical image segmentation, with its precise lesion localization capabilities, serves as a core component in multimedia medical applications and intelligent diagnostic assistance systems. Recent innovations in network architectures significantly improve segmentation performance. However, the Non-Effective Samples (NES) on model optimization receive little attention. These samples are characterized by minimal gradient variations in loss during training and exhibit a slight contribution to model optimization. They encompass well-segmented samples with near-zero loss values and challenging samples with consistently high loss values. Especially, when NES accumulate, the model will fall into an optimization trap, causing the optimization to stagnate. To address this issue, we propose a lightweight plug-and-play Gradient-Aware Sample Selection and Reactivation Strategy (GA-SRS) that efficiently identifies and revitalizes the training potential of NES. Firstly, GA-SRS filters NES out based on the historical training information of samples and the variations in the loss gradient during the training process. Then, GA-SRS revitalizes the training values of these samples through strong data augmentation. Extensive experiments on four public datasets and three general models demonstrate the effectiveness of GA-SRS. For example, GA-SRS helps improve the IoU metric of U-KAN from 67.20% to 71.24% on the BUSI and from 81.20% to 82.51% on the ISIC dataset, achieving state-of-the-art experimental results.

Semi-supervised learning suffers from the imbalance of labeled and unlabeled training data in the video surveillance scenario. In this paper, we propose a new semi-supervised learning method called SIAVC for industrial accident video classification. Specifically, we design a video augmentation module called the Super Augmentation Block (SAB). SAB adds Gaussian noise and randomly masks video frames according to historical loss on the unlabeled data for model optimization. Then, we propose a Video Cross-set Augmentation Module (VCAM) to generate diverse pseudo-label samples from the high-confidence unlabeled samples, which alleviates the mismatch of sampling experience and provides high-quality training data. Additionally, we construct a new industrial accident surveillance video dataset with frame-level annotation, namely ECA9, to evaluate our proposed method. Compared with the state-of-the-art semi-supervised learning based methods, SIAVC demonstrates outstanding video classification performance, achieving 88.76% and 89.13% accuracy on ECA9 and Fire Detection datasets, respectively. The source code and the constructed dataset ECA9 will be released inhttps://github.com/AlchemyEmperor/SIAVC.

The detection of cracks is essential for assessing and maintaining building and road safety. However, the large appearance variations and the complex topological structures of cracks bring challenges to automatic crack detection. To alleviate the above challenges, we propose a deep multi-scale crack feature learning model called DeepCrackAT for crack segmentation, which is based on an encoder–decoder network with feature tokenization mechanism and attention mechanism. Specifically, we use hybrid dilated convolutions in the first three layers of the encoder–decoder to increase the network’s receptive field and capture more crack information. Then, we introduce a tokenized multilayer perceptron (Tok-MLP) in the last two layers of the encoder–decoder to tokenize and project high-dimensional crack features into low-dimensional space. This helps to reduce parameters and enhance the network’s ability of noise resistance. Next, we concatenate the features corresponding to the encoder–decoder layers and introduce the convolutional block attention module (CBAM) to enhance the network’s perception of the critical crack region. Finally, the five-layer features are fused to generate a binary segmentation map of the crack image. We conducted extensive experiments and ablation studies on two real-world crack datasets, and DeepCrackAT achieved 97.41% and 97.25% accuracy on these datasets, respectively. The experimental results show that the proposed method outperforms the current state-of-the-art methods.