Semantic segmentation is a challenging problem in computer vision. Many applications, such as autonomous driving and robot navigation with urban road scene, need accurate and efficient segmentation. Most state-of-the-art methods focus on accuracy, rather than efficiency. In this paper, we propose a more efficient neural network architecture, which has fewer parameters, for semantic segmentation in the urban road scene. An asymmetric encoder-decoder structure based on ResNet is used in our model. In the first stage of encoder, we use continuous factorized block to extract low-level features. Continuous dilated block is applied in the second stage, which ensures that the model has a larger view field, while keeping the model small-scale and shallow. The down sampled features from encoder are up sampled with decoder to the same-size output as the input image and the details refined. Our model can achieve end-to-end and pixel-to-pixel training without pre-training from scratch. The parameters of our model are only 0.2M, 100x less than those of others such as SegNet, etc. Experiments are conducted on five public road scene datasets (CamVid, CityScapes, Gatech, KITTI, Road Detection and KITTI Semantic Segmentation), and the results demonstrate that our model can achieve better performance.

Wildfires have devastating consequences on ecological systems and human lives. Accurate and fast wildfire detection is crucial to reducing damage. The existing smoke detection algorithms using convolution neural network are mostly based on the classification of smoke images or patches, whereas the traditional smoke detection algorithms are often necessary to extract multiple features for integration. With the methods mentioned above, false positive is always an insurmountable problem in wildfire smoke detection. Moreover, there are few studies on the detection of wildfire smoke. Thus, to detect the wildfire smoke more intelligent, a 3D parallel fully convolutional network for wildfire smoke detection is proposed to segment the smoke regions in video sequences. Wildfire smoke detection is considered as a segmentation problem in this paper. There are more than 90 videos including various scene used for training and test. Experiments have demonstrated that our architecture can segment smoke regions accurately and eliminate the interference of natural scenes. Smoke targets in multiple scene can be detected accurately and quickly.

Salient Object Detection aims to detect the most visually distinctive objects in an image. We solve this problem by introducing the average pool to explore the multi-level deep average pool convolution features different from the max pool information. Based on the U-net structure, we propose an Average- and Max-Pool Network (AMPNet) that leverages the average- and max-pool modules to integrate the multi-level complementary contextual features in the spatial and channel-wise dimensions, respectively. The complementary contextual features generated by our network can improve the completeness of detected objects. It has been observed that the non-salient regions are misrecognized as the salient objects because of the redundant information contained in the multi-level convolution features. To address the problem, two top-down feedback paths are introduced based on the above two modules, and their top-level semantic guidance information is fully utilized to improve the accuracy of salient objects detection. Finally, we apply the Feature Fusion Module and Deep Supervision Mechanism to further improve the performance of the network over different datasets. Experimental results on six benchmark datasets show that our network is on par with state-of-the-art approaches. Our method runs at more than 45 FPS (based on VGG) and 35 FPS (based on ResNet) on a single GPU and meets real-time requirements.

Although high-accuracy networks have been applied to semantic segmentation at present, their inference speeds remain slow. A trade-off between accuracy and speed is demanded for real-time applications. To approach this problem, we propose Multi-Feature Fusion Network (MFNet) with real-time efficient prediction capacity. MFNet adopts three branches (attention, semantic and spatial information) to capture low-level and high-level features. Additionally, MFNet exerts asymmetric factorized (AF) blocks to extract local and long-range features. As a result, without any pre-training or post-processing, MFNet using only 1.34 M parameters, achieves 72.1% mean intersection over union (mIoU) on the Cityscapes test set at a speed of 116 frames per second (FPS), with $512\times1024$ high resolution on a single Titan Xp graphics card. Our network’s performance stands out from other state-of-the-art networks on four datasets (Cityscapes, CamVid, KITTI, and Gatech).

At present, many studies have shown that partitioning the gait sequence and its feature map can improve the accuracy of gait recognition. However, most models just cut the feature map at a fixed single scale, which loses the dependence between various parts. So, our paper proposes a structure called Part Feature Relationship Extractor (PFRE) to discover all of the relationships between each parts for gait recognition. The paper uses PFRE and a Convolutional Neural Network (CNN) to form the RPNet. PFRE is divided into two parts. One part that we call the Total-Partial Feature Extractor (TPFE) is used to extract the features of different scale blocks, and the other part, called the Adjacent Feature Relation Extractor (AFRE), is used to find the relationships between each block. At the same time, the paper adjusts the number of input frames during training to perform quantitative experiments and finds the rule between the number of input frames and the performance of the model. Our model is tested on three public gait datasets, CASIA-B, OU-LP and OU-MVLP. It exhibits a significant level of robustness to occlusion situations, and achieves accuracies of 92.82% and 80.26% on CASIA-B under BG # and CL # conditions, respectively. The results show that our method reaches the top level among state-of-the-art methods.