In this paper, we demonstrate an energy-efficient real-time object detection and classification system featuring a hybrid event-based frame generation pipeline and a background-removal region proposal algorithm. The event-based frame is generated by aggregating active events within a programmable time interval, generating an event-based binary image (EBBI). This approach enables the utilization of low-complexity algorithms for denoising and object detection. The background-removal region proposal algorithm reduces memory requirements and removes dynamic backgrounds, leading to better detection performance. The proposed system is demonstrated on Zynq-7000 FPGA device with a DAVIS346 sensor. Experimental results show that the proposed system achieves comparable detection accuracy while requiring significantly less computation than existing event-based trackers.

Neuromorphic vision sensors (NVSs) mimic the function of the human visual system, with significant energy-saving potential in IoT-based object detection systems. Unlike conventional sensors, NVSs only generate asynchronous spiking events in response to changes in light intensity. However, the inherent noise generated by NVSs causes a degradation of detection performance. Moreover, an interested object usually occupies only a portion of the entire image frame. Therefore, a real-time, accurate event-based object detection system is needed to identify the region of interest (Rol) and leverage this spatial redundancy to reduce computational load in subsequent recognition modules. In this article, we present an energy-efficient real-time object detection system featuring a hybrid event-based frame generation pipeline and a background-removal region proposal algorithm. The event-based frame is generated by aggregating active events within a programmable time interval, generating an event-based binary image (EBBI). This approach enables the utilization of low-complexity algorithms for denoising and object detection. The background-removal region proposal algorithm reduces memory requirements and removes dynamic backgrounds, leading to better detection performance. The proposed system is demonstrated on Zynq-7000 FPGA device with a DAVIS346 sensor. Experimental results show that the proposed system achieves comparable accuracy while requiring significantly less computation than existing event-based trackers.

Dynamic vision sensors (DVS) have become prevalent in edge vision applications due to their low power and short latency attributes. However, current DVS-based object tracking systems suffer from high power consumption or long processing latency due to high computing intensity of the object detection algorithms. This paper proposes an energy-efficient object detection system through algorithm and hardware co-optimization. We design hardware-efficient denoising and region proposal (RP) algorithms to reduce on-chip memory usage and power consumption. Besides, the processing latency is dramatically reduced thanks to the less computing complexity. The devised algorithm is executed on a heterogeneous platform, with segments particularly sensitive to latency being accelerated via FPGA. An RP processor, supporting both parallel and systolic computing modes, is developed to facilitate the computing-intensive RP generation. Remarkably, the proposed system reduces the on-chip memory by 95.3% in contrast to traditional methods that employ connected component labeling. Moreover, the processing time per frame stands at 92.2 ms, marking a reduction of 82.4% compared to CPU-only operations.

Accurate approaches for quantifying muscle fibers are essential in biomedical research and meat production. In this study, we address the limitations of existing approaches for hematoxylin and eosin-stained muscle fibers by manually and semiautomatically labeling over 660 000 muscle fibers to create a large dataset. Subsequently, an automated image segmentation and quantification tool named MyoV is designed using mask regions with convolutional neural networks and a residual network and feature pyramid network as the backbone network. This design enables the tool to allow muscle fiber processing with different sizes and ages. MyoV, which achieves impressive detection rates of 0.93-0.96 and precision levels of 0.91-0.97, exhibits a superior performance in quantification, surpassing both manual methods and commonly employed algorithms and software, particularly for whole slide images (WSIs). Moreover, MyoV is proven as a powerful and suitable tool for various species with different muscle development, including mice, which are a crucial model for muscle disease diagnosis, and agricultural animals, which are a significant meat source for humans. Finally, we integrate this tool into visualization software with functions, such as segmentation, area determination and automatic labeling, allowing seamless processing for over 400 000 muscle fibers within a WSI, eliminating the model adjustment and providing researchers with an easy-to-use visual interface to browse functional options and realize muscle fiber quantification from WSIs.

The application of deep learning in time-series prediction has developed gradually. In this paper, we propose a deep generative network model for feature extraction of multivariate time series, namely, mutual information variational autoencoders (MI-VAE). In the architecture of the proposed model, we use the latent space of VAE for feature learning, which can extract the essential features of multivariate time-series data effectively. The latent space employed directly as a feature extractor can avoid poor interpretability of model. In addition, we introduce a mutual information term into the loss function, which improves the expression capability and accuracy of model. The proposed model, combining the merits of VAE and mutual information, extracts features for multivariate time-series data from a new perspective. The Lorenz system and Beijing air quality time series are used to test performance of the proposed model and comparative models. Results show that the proposed model is superior to other similar models in terms of accuracy and expression capability of latent space.