In recent years, deep learning has dominated medical image segmentation. Encoder-decoder architectures, such as U-Net, can be used in state-of-the-art models with powerful designs that are achieved by implementing skip connections that propagate local information from an encoder path to a decoder path to retrieve detailed spatial information lost by pooling operations. Despite their effectiveness for segmentation, these naïve skip connections still have some disadvantages. First, multi-scale skip connections tend to use unnecessary information and computational sources, where likable low-level encoder features are repeatedly used at multiple scales. Second, the contextual information of the low-level encoder feature is insufficient, leading to poor performance for pixel-wise recognition when concatenating with the corresponding high-level decoder feature. In this study, we propose a novel spatial-channel attention gate that addresses the limitations of plain skip connections. This can be easily integrated into an encoder-decoder network to effectively improve the performance of the image segmentation task. Comprehensive results reveal that our spatial-channel attention gate remarkably enhances the segmentation capability of the U-Net architecture with a minimal computational overhead added. The experimental results show that our proposed method outperforms the conventional deep networks in term of Dice score, which achieves 71.72%.

Block-based coding introduces an undesirable discontinuity between neighboring blocks in reconstructed images. This image degradation, referred to as blocking artifacts, arises mainly due to the loss of inter-block correlation in the quantization process of discrete cosine transform coefficients. In many multimedia broadcasting applications, such as a television, decoded video sequences suffer from blocking artifacts. In this paper, we present a novel post-processing algorithm based on increment of inter-block correlation aimed at reducing blocking artifacts. We first smooth the three lowest frequency discrete cosine transform (DCT) coefficients between neighboring blocks, in order to reduce blocking artifacts in the flat region, which are most sensitive to the human visual system. We then group each edge block and its matched blocks together and apply group-based filtering to increase the correlation between grouped blocks. This suppresses blocking artifacts in the edge region while preserving details. In addition, the algorithm is extended to reduce flickering artifacts as well as blocking artifacts in video sequences. Experimental results show that the proposed method successfully alleviates blocking artifacts in both images and videos coded with low bit-rates.

Object recognition is conducted using red, green, and blue (RGB) images in object recognition studies. However, RGB images in low-light environments or environments where other objects occlude the target objects cause poor object recognition performance. In contrast, infrared (IR) images provide acceptable object recognition performance in these environments because they detect IR waves rather than visible illumination. In this paper, we propose an inter- and intra-weighted cross-fusion network (Infusion-Net), which improves object recognition performance by combining the strengths of the RGB-IR image pairs. Infusion-Net connects dual object detection models using a high-frequency (HF) assistant (HFA) to combine the advantages of RGB-IR images. To extract HF components, the HFA transforms input images into a discrete cosine transform domain. The extracted HF components are weighted via pretrained inter- and intra-weights for feature-domain cross-fusion. The inter-weighted fused features are transmitted to each other’s networks to complement the limitations of each modality. The intra-weighted features are also used to enhance any insufficient HF components of the target objects. Thus, the experimental results present the superiority of the proposed network and present improved performance of the multispectral object recognition task.

Physiological signals are widely used in the recognition of affective status. Recording of such physiological signals involves elicitation of emotions through different stimuli including video-based stimulus. Considering that the same stimulus videos often induce different emotions in different individuals, emotion recognition in such a scenario requires consideration of the individual differences in the consumption of the stimulus content. With this as our goal, we present a Physiological dataset for Multimodal Emotion Recognition (PhyMER) for studying emotion through physiological response with personality as a context. The PhyMER dataset consists of electroencephalogram (EEG), electrodermal activity (EDA), blood volume pulse (BVP), and skin temperature along with the personality traits of 30 participants. We collected the video-based stimulus dataset for emotion elicitation and developed a web-based annotation tool for labeling felt emotions. We compared the stimulus labels and the self-annotation of felt emotions labeled during physiological data recording. Correlation among personalities was analyzed to study the impact of personality on the intensity of emotions in arousal and valence dimensions. Finally, we proposed a baseline model for the classification of emotions using physiological signals. The dataset is publicly available to the academic community for analysis of affective states and the development of emotion recognition models.

Most crack‐detection methods adopt a pixel‐level segmentation‐based approach, which requires considerable time and complexity to detect the pixel area of the crack. Unlike a pixel‐level segmentation‐based approach, in this paper, the authors proposed an AugMoCrack network, a bounding box‐level crack detection approach for weakly supervised crack detection achieved by augmenting the training data with Poisson blending, as well as high‐frequency discrete cosine transform‐based features. The proposed AugMoCrack detects the box position of the crack object from a morphological perspective, such as neighbour connectivity within the crack pixels and crack‐area fitting. Based on this perspective, the authors also proposed new morphological attention loss functions for considering the neighbour connectivity and the box area border. Specifically, the authors trained the AugMoCrack network using two datasets and verified its performance based on 591 validation images in the concrete crack dataset and 672 validation images in the Crack500 dataset. Compared with the baseline architecture, with the authors’ proposed network, the authors achieved increases of approximately 4.5% points and 2.5% points in the mean average precision (mAP) in the concrete crack and Crack500 datasets, respectively. The proposed network also outperforms previous state‐of‐the‐art crack‐detection methods in a weakly supervised learning environment where the training data are insufficient.