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Accuracy Assessment and Guidelines for Manual Traffic Counts from Pre-Recorded Video Data
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作者 Mishuk Majumder Chester Wilmot 《Journal of Transportation Technologies》 2023年第4期497-523,共27页
Traffic count is the fundamental data source for transportation planning, management, design, and effectiveness evaluation. Recording traffic flow and counting from the recorded videos are increasingly used due to con... Traffic count is the fundamental data source for transportation planning, management, design, and effectiveness evaluation. Recording traffic flow and counting from the recorded videos are increasingly used due to convenience, high accuracy, and cost-effectiveness. Manual counting from pre-recorded video footage can be prone to inconsistencies and errors, leading to inaccurate counts. Besides, there are no standard guidelines for collecting video data and conducting manual counts from the recorded videos. This paper aims to comprehensively assess the accuracy of manual counts from pre-recorded videos and introduces guidelines for efficiently collecting video data and conducting manual counts by trained individuals. The accuracy assessment of the manual counts was conducted based on repeated counts, and the guidelines were provided from the experience of conducting a traffic survey on forty strip mall access points in Baton Rouge, Louisiana, USA. The percentage of total error, classification error, and interval error were found to be 1.05 percent, 1.08 percent, and 1.29 percent, respectively. Besides, the percent root mean square errors (RMSE) were found to be 1.13 percent, 1.21 percent, and 1.48 percent, respectively. Guidelines were provided for selecting survey sites, instruments and timeframe, fieldwork, and manual counts for an efficient traffic data collection survey. 展开更多
关键词 Traffic Survey Counting Error Transportation Planning Total Error Collecting video data Classification Error Standard Guidelines Repeated Counts Interval Error
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Design and Implementation of GIS Data Production System for Expressway Video and Road Infostructure 被引量:2
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作者 Yuan Liu Jianhua Liu Guoqiang Feng 《International Journal of Geosciences》 2021年第1期23-38,共16页
The expressway is necessary for the development of the modern transportation industry, and the level of expressway construction reflects the overall grade of national or regional economic development. In order to proc... The expressway is necessary for the development of the modern transportation industry, and the level of expressway construction reflects the overall grade of national or regional economic development. In order to process the expressway road property data information, based on the current mainstream Windows operating system, this study utilizes Geographic Information System (GIS) development technology, road video processing technology, and spatial data mining method to design and develop an expressway video and road infostructure GIS data production system. The system designs a multi-layer distributed application model in accordance with the ideas and methods of GIS engineering and the characteristics of road production data. In addition, according to the characteristics and specification requirements of basic geographic data, the road production database of spatial data and attribute data integrated storage is constructed by combining database and spatial data engine. Through the development of the GIS data production system for expressway video and road infostructure, various functions such as generation of road property data, dynamic management of road infostructure, and visualization of spatial information have been realized. The system focuses on improving the production efficiency and automation level of expressway production data and meet</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> the construction requirements for modernization, informatization, and intelligence of expressways. 展开更多
关键词 EXPRESSWAY GIS Road Infostructure video Road Property data
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Using microscopic video data measures for driver behavior analysis during adverse winter weather:opportunities and challenges 被引量:1
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作者 Ting Fu Sohail Zangenehpour +2 位作者 Paul St-Aubin Liping Fu Luis F.Miranda-Moreno 《Journal of Modern Transportation》 2015年第2期81-92,共12页
This paper presents a driver behavior analysis using microscopic video data measures including vehicle speed, lane-changing ratio, and time to collision. An analytical framework was developed to evaluate the effect of... This paper presents a driver behavior analysis using microscopic video data measures including vehicle speed, lane-changing ratio, and time to collision. An analytical framework was developed to evaluate the effect of adverse winter weather conditions on highway driving behavior based on automated (computer) and manual methods. The research was conducted through two case studies. The first case study was conducted to evaluate the feasibility of applying an au- tomated approach to extracting driver behavior data based on 15 video recordings obtained in the winter 2013 at three dif- ferent locations on the Don Valley Parkway in Toronto, Canada. A comparison was made between the automated approach and manual approach, and issues in collecting data using the automated approach under winter conditions were identified. The second case study was based on high quality data collected in the winter 2014, at a location on Highway 25 in Montreal, Canada. The results demonstrate the effectiveness of the automated analytical framework in analyzing driver behavior, as well as evaluating the impact of adverse winter weather conditions on driver behavior. This approach could be applied to evaluate winter maintenance strategies and crash risk on highways during adverse winter weather conditions. 展开更多
关键词 WINTER video data collection Issues Driver behavior Time to collision Winter roadmaintenance
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Analysis of video head impulse test saccades data in patients with vestibular migraine or probable vestibular migraine 被引量:1
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作者 Yi Du Xingjian Liu +2 位作者 Lili Ren Yu Wang Ziming Wu 《Journal of Otology》 CSCD 2022年第4期197-202,共6页
Objective:Saccades accompanied by normal gain in video head impulse tests(vHIT)are often observed in patients with vestibular migraine(VM).However,they are not considered as an independent indicator,reducing their uti... Objective:Saccades accompanied by normal gain in video head impulse tests(vHIT)are often observed in patients with vestibular migraine(VM).However,they are not considered as an independent indicator,reducing their utility in diagnosing VM.To better understand clinical features of VM,it is necessary to understand raw saccades data.Methods:Fourteen patients with confirmed VM,45 patients with probable VM(p-VM)and 14 agematched healthy volunteers were included in this study.Clinical findings related to spontaneous nystagmus(SN),positional nystagmus(PN),head-shaking nystagmus(HSN),caloric test and vHIT were recorded.Raw saccades data were exported and numbered by their sequences,and their features analyzed.Results:VM patients showed no SN,PN or HSN,and less than half of them showed unilateral weakness(UW)on caloric test.The first saccades from lateral semicircular canal stimulation were the most predominant for both left and right sides.Neither velocity nor time parameters were significantly different when compared between the two sides.Most VM patients(86%)exhibited small saccades,around 35%of the head peak velocity,with a latency of 200e400 ms.Characteristics of saccades were similar in patients with p-VM.Only four normal subjects showed saccades,all unilateral and seemingly random.Conclusions:Small saccades involving bilateral semicircular canals with a scattered distribution pattern are common in patients with VM and p-VM. 展开更多
关键词 Vestibular migraine Probable vestibular migraine video head impulse test SACCADE data analysis
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Research on Big Data and Artificial Intelligence Aided Decision-Making Mechanism with the Applications on Video Website Homemade Program Innovation 被引量:1
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作者 Ting Li 《International Journal of Technology Management》 2016年第3期21-23,共3页
In this paper, we conduct research on the big data and the artificial intelligence aided decision-making mechanism with the applications on video website homemade program innovation. Make homemade video shows new medi... In this paper, we conduct research on the big data and the artificial intelligence aided decision-making mechanism with the applications on video website homemade program innovation. Make homemade video shows new media platform site content production with new possible, as also make the traditional media found in Internet age, the breakthrough point of the times. Site homemade video program, which is beneficial to reduce copyright purchase demand, reduce the cost, avoid the homogeneity competition, rich advertising marketing at the same time, improve the profit pattern, the organic combination of content production and operation, complete the strategic transformation. On the basis of these advantages, once the site of homemade video program to form a brand and a higher brand influence. Our later research provides the literature survey for the related issues. 展开更多
关键词 Bid data Artificial Intelligence DECISION-MAKING video Website Program Innovation.
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Improved Video Steganography with Dual Cover Medium,DNA and Complex Frames 被引量:2
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作者 Asma Sajjad Humaira Ashraf +3 位作者 NZ Jhanjhi Mamoona Humayun Mehedi Masud Mohammed A.AlZain 《Computers, Materials & Continua》 SCIE EI 2023年第2期3881-3898,共18页
The most valuable resource on the planet is no longer oil,but data.The transmission of this data securely over the internet is another challenge that comes with its ever-increasing value.In order to transmit sensitive... The most valuable resource on the planet is no longer oil,but data.The transmission of this data securely over the internet is another challenge that comes with its ever-increasing value.In order to transmit sensitive information securely,researchers are combining robust cryptography and steganographic approaches.The objective of this research is to introduce a more secure method of video steganography by using Deoxyribonucleic acid(DNA)for embedding encrypted data and an intelligent frame selection algorithm to improve video imperceptibility.In the previous approach,DNA was used only for frame selection.If this DNA is compromised,then our frames with the hidden and unencrypted data will be exposed.Moreover the frame selected in this way were random frames,and no consideration was made to the contents of frames.Hiding data in this way introduces visible artifacts in video.In the proposed approach rather than using DNA for frame selection we have created a fakeDNA out of our data and then embedded it in a video file on intelligently selected frames called the complex frames.Using chaotic maps and linear congruential generators,a unique pixel set is selected each time only from the identified complex frames,and encrypted data is embedded in these random locations.Experimental results demonstrate that the proposed technique shows minimum degradation of the stenographic video hence reducing the very first chances of visual surveillance.Further,the selection of complex frames for embedding and creation of a fake DNA as proposed in this research have higher peak signal-to-noise ratio(PSNR)and reduced mean squared error(MSE)values that indicate improved results.The proposed methodology has been implemented in Matlab. 展开更多
关键词 video steganography data encryption DNA embedding frame selection
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A Novel Video Data-Source Authentication Model Based on Digital Watermarking and MAC in Multicast
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作者 ZHAO Anjun LU Xiangli GUO Lei 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1257-1261,共5页
A novel video data authentication model based on digital video watermarking and MAC (message authentication code) in multicast protocol is proposed in this paper, The digital watermarking which composes of the MAC o... A novel video data authentication model based on digital video watermarking and MAC (message authentication code) in multicast protocol is proposed in this paper, The digital watermarking which composes of the MAC of the significant vid eo content, the key and instant authentication data is embedded into the insignificant video component by the MLUT (modified look-up table) video watermarking technology. We explain a method that does not require storage of each data packet for a time, thus making receiver not vulnerable to DOS (denial of service) attack. So the video packets can be authenticated instantly without large volume buffer in the receivers. TESLA (timed efficient stream loss tolerant authentication) does not explain how to select the suitable value for d, which is an important parameter in multicast source authentication. So we give a method to calculate the key disclosure delay (number of intervals). Simulation results show that the proposed algorithms improve the performance of data source authentication in multicast. 展开更多
关键词 video data authentication MULTICAST MAC(message authentication code) digital watermarking MLUT(modifled look-up table)
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Reversible Data Hiding Based on Run-Level Coding in H.264/AVC Video Streams
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作者 Yi Chen Hongxia Wang Xuyun Zhang 《Computers, Materials & Continua》 SCIE EI 2020年第5期911-922,共12页
This paper presents a reversible data hiding(RDH)method,which is designed by combining histogram modification(HM)with run-level coding in H.264/advanced video coding(AVC).In this scheme,the run-level is changed for em... This paper presents a reversible data hiding(RDH)method,which is designed by combining histogram modification(HM)with run-level coding in H.264/advanced video coding(AVC).In this scheme,the run-level is changed for embedding data into H.264/AVC video sequences.In order to guarantee the reversibility of the proposed scheme,the last nonzero quantized discrete cosine transform(DCT)coefficients in embeddable 4×4 blocks are shifted by the technology of histogram modification.The proposed scheme is realized after quantization and before entropy coding of H.264/AVC compression standard.Therefore,the embedded information can be correctly extracted at the decoding side.Peak-signal-noise-to-ratio(PSNR)and Structure similarity index(SSIM),embedding payload and bit-rate variation are exploited to measure the performance of the proposed scheme.Experimental results have shown that the proposed scheme leads to less SSIM variation and bit-rate increase. 展开更多
关键词 Reversible data hiding run-level coding visual quality bit-rate increase H.264/AVC video streams
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Recommendations for Big Data in Online Video Quality of Experience Assessment
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作者 Ethan Court Kapilan Radhakrishnan +1 位作者 Kemi Ademoye Stephen Hole 《Journal of Computer and Communications》 2016年第5期24-31,共8页
Real-time video application usage is increasing rapidly. Hence, accurate and efficient assessment of video Quality of Experience (QoE) is a crucial concern for end-users and communication service providers. After cons... Real-time video application usage is increasing rapidly. Hence, accurate and efficient assessment of video Quality of Experience (QoE) is a crucial concern for end-users and communication service providers. After considering the relevant literature on QoS, QoE and characteristics of video trans-missions, this paper investigates the role of big data in video QoE assessment. The impact of QoS parameters on video QoE are established based on test-bed experiments. Essentially big data is employed as a method to establish a sensible mapping between network QoS parameters and the resulting video QoE. Ultimately, based on the outcome of experiments, recommendations/re- quirements are made for a Big Data-driven QoE model. 展开更多
关键词 Quality of Experience QOE Big data ONLINE video TRAFFIC
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A Multi-objective Optimization Data Scheduling Algorithm for P2P Video Streaming
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作者 Pingshan Liu Xiaoyi Xiong Guimin Huang 《国际计算机前沿大会会议论文集》 2017年第2期43-45,共3页
In P2P video streaming, each peer requests its wanted streaming data from others and responses others' requests by its data scheduling algorithm. Recent years, some data scheduling algorithms are proposed either t... In P2P video streaming, each peer requests its wanted streaming data from others and responses others' requests by its data scheduling algorithm. Recent years, some data scheduling algorithms are proposed either to optimize the perceived video quality, or to optimize the network throughput. However, optimizing the perceived video quality may lead to low utilization of the senders'upload capacity. On the other hand, optimizing the network throughput may lead to the degrading perceived quality, for some emergent data may not be transmitted in time. In this paper, to improve the two objectives simultaneously, we formulate the data scheduling problem as a multi-objective model. In the formulation, we not only consider the segment quality and emergency which affect the perceived video quality, but also consider the rarity of the segments, which influences the network throughput. Then, we propose a distributed data scheduling algorithm to solve the multi-objective problem in polynomial time. Through simulations, we show the proposed algorithm outperforms other conventional algorithms in perceived video quality and utilization of peers' upload capacity. 展开更多
关键词 PEER-TO-PEER video STREAMING data SCHEDULING THROUGHPUT QUALITY optimization
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Human Stress Recognition by Correlating Vision and EEG Data
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作者 S.Praveenkumar T.Karthick 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期2417-2433,共17页
Because stress has such a powerful impact on human health,we must be able to identify it automatically in our everyday lives.The human activity recognition(HAR)system use data from several kinds of sensors to try to r... Because stress has such a powerful impact on human health,we must be able to identify it automatically in our everyday lives.The human activity recognition(HAR)system use data from several kinds of sensors to try to recognize and evaluate human actions automatically recognize and evaluate human actions.Using the multimodal dataset DEAP(Database for Emotion Analysis using Physiological Signals),this paper presents deep learning(DL)technique for effectively detecting human stress.The combination of vision-based and sensor-based approaches for recognizing human stress will help us achieve the increased efficiency of current stress recognition systems and predict probable actions in advance of when fatal.Based on visual and EEG(Electroencephalogram)data,this research aims to enhance the performance and extract the dominating characteristics of stress detection.For the stress identification test,we utilized the DEAP dataset,which included video and EEG data.We also demonstrate that combining video and EEG characteristics may increase overall performance,with the suggested stochastic features providing the most accurate results.In the first step,CNN(Convolutional Neural Network)extracts feature vectors from video frames and EEG data.Feature Level(FL)fusion that combines the features extracted from video and EEG data.We use XGBoost as our classifier model to predict stress,and we put it into action.The stress recognition accuracy of the proposed method is compared to existing methods of Decision Tree(DT),Random Forest(RF),AdaBoost,Linear Discriminant Analysis(LDA),and KNearest Neighborhood(KNN).When we compared our technique to existing state-of-the-art approaches,we found that the suggested DL methodology combining multimodal and heterogeneous inputs may improve stress identification. 展开更多
关键词 Mental stress physiological data XGBoost feature fusion DEAP video data EEG CNN HAR
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Deeply‐Recursive Attention Network for video steganography
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作者 Jiabao Cui Liangli Zheng +4 位作者 Yunlong Yu Yining Lin Huajian Ni Xin Xu Zhongfei Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1507-1523,共17页
Video steganography plays an important role in secret communication that conceals a secret video in a cover video by perturbing the value of pixels in the cover frames.Imperceptibility is the first and foremost requir... Video steganography plays an important role in secret communication that conceals a secret video in a cover video by perturbing the value of pixels in the cover frames.Imperceptibility is the first and foremost requirement of any steganographic approach.Inspired by the fact that human eyes perceive pixel perturbation differently in different video areas,a novel effective and efficient Deeply‐Recursive Attention Network(DRANet)for video steganography to find suitable areas for information hiding via modelling spatio‐temporal attention is proposed.The DRANet mainly contains two important components,a Non‐Local Self‐Attention(NLSA)block and a Non‐Local Co‐Attention(NLCA)block.Specifically,the NLSA block can select the cover frame areas which are suitable for hiding by computing the correlations among inter‐and intra‐cover frames.The NLCA block aims to effectively produce the enhanced representations of the secret frames to enhance the robustness of the model and alleviate the influence of different areas in the secret video.Furthermore,the DRANet reduces the model parameters by performing similar operations on the different frames within an input video recursively.Experimental results show the proposed DRANet achieves better performance with fewer parameters than the state‐of‐the‐art competitors. 展开更多
关键词 data privacy video processing
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视频侦查技术关键及其发展展望 被引量:1
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作者 赵秀萍 《辽宁警察学院学报》 2024年第2期79-87,共9页
视频侦查技术的核心是通过视频图像的提取、查看、分析和研判来获取侦查线索、固定涉案证据。多年来经过在实战应用中不断地发展创新,视频侦查技术形成了自己独特的关键技术体系:视频信息分析解读技术是侦查应用和证据固定的基础和核心... 视频侦查技术的核心是通过视频图像的提取、查看、分析和研判来获取侦查线索、固定涉案证据。多年来经过在实战应用中不断地发展创新,视频侦查技术形成了自己独特的关键技术体系:视频信息分析解读技术是侦查应用和证据固定的基础和核心;视频证据固定保全技术的规范是审判中心主义的客观要求,可以获取视频侦查记录报告、视频检验鉴定报告或视频数据关联报告;低质量视频图像的增强恢复技术专业性强,应用范围窄,技术成熟度高,然而它不断面临新的挑战。目前,视频数据的智能应用在大数据背景下变得越来越重要,仍需进一步突破视频自动识别技术的应用范畴,建立完善多层次的视频数据综合应用体系,打造适应不同业务需要的视频数据实战应用模型。 展开更多
关键词 视频侦查技术 视频解析 证据固定 图像处理 数据智能
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中国石油井下作业数字化监督发展问题与对策 被引量:1
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作者 张绍辉 黄伟和 +5 位作者 毕国强 张晓辉 张建利 文虎成 李海军 田涛 《石油工业技术监督》 2024年第5期1-7,共7页
阐述了中国石油井下作业数字化监督在监督人员数字化管理、施工队伍数字化监督、施工作业数字化监督、井场环境数字化监督4个方面的发展现状。分析了井下作业数字化监督发展面临数字化监督管理制度不健全、监督数据标准不统一、数字化... 阐述了中国石油井下作业数字化监督在监督人员数字化管理、施工队伍数字化监督、施工作业数字化监督、井场环境数字化监督4个方面的发展现状。分析了井下作业数字化监督发展面临数字化监督管理制度不健全、监督数据标准不统一、数字化智能监督技术不完善、缺少统一的数字化智能监督平台、监督数据价值挖掘不深入5个方面的主要问题。提出了制定井下作业数字化监督管理制度、建立井下作业监督数据标准、攻关数字化智能监督关键技术、研发井下作业数字化智能监督平台、提升监督大数据分析应用水平5项数字化监督发展对策。展望了井下作业数字化监督建设发展后在提升监督人员履职效率、降低监督人力资源成本、提升工程质量、保障施工安全与环保4个方面的预期成效。 展开更多
关键词 井下作业 数字化监督 数据标准 修井机 视频监控 监督平台
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短视频消费时长能够反映就业率吗?
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作者 白小虎 程开明 叶子豪 《商业经济与管理》 北大核心 2024年第3期92-104,共13页
鉴于现行就业统计方式不能及时、准确反映经济运行形势,如何利用大数据对现有统计指标进行补充成为一个重要问题。鉴于短视频消费已经成为当今社会主要的休闲娱乐方式,文章将短视频消费纳入效用函数,通过失业人员与雇员在时间分配上的差... 鉴于现行就业统计方式不能及时、准确反映经济运行形势,如何利用大数据对现有统计指标进行补充成为一个重要问题。鉴于短视频消费已经成为当今社会主要的休闲娱乐方式,文章将短视频消费纳入效用函数,通过失业人员与雇员在时间分配上的差异,揭示全社会用于观看短视频的时间与就业率之间存在的理论联系。通过计量分析,研究发现基于抖音在线人数计算的估计值与描述失业者寻找工作行为的百度搜索指数呈现正相关关系,可以借助短视频观看时长变动说明失业者寻找工作行为的变化。基于抖音在线人数估计的劳动参与率与16—24岁城镇调查失业率存在显著负相关关系,两者的皮尔逊相关系数为-0.862,因此估计的劳动参与率可以作为城镇调查失业率,特别是16—24岁劳动力调查失业率的补充。 展开更多
关键词 就业 失业率 大数据 短视频 抖音
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涉Sora等文生视频危害行为的刑法规制
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作者 刘宪权 余越洋 《华东师范大学学报(哲学社会科学版)》 北大核心 2024年第5期89-102,172,共15页
Sora等文生视频的应用将对刑法的法益理论产生重大影响。应将文生视频生成内容纳入作品范围。文生视频是其生成内容的作者但尚不是权利主体,应将相关著作财产权转移给使用人。涉文生视频强制猥亵、侮辱罪所侵害法益应当包括精神损害的... Sora等文生视频的应用将对刑法的法益理论产生重大影响。应将文生视频生成内容纳入作品范围。文生视频是其生成内容的作者但尚不是权利主体,应将相关著作财产权转移给使用人。涉文生视频强制猥亵、侮辱罪所侵害法益应当包括精神损害的内容。文生视频的应用改变了视频创作行业的社会关系,进而会改变相关犯罪行为法益侵害性程度的判断标准。涉文生视频犯罪主要涉及侵犯人身权利类犯罪、侵犯财产权利类犯罪以及寻衅滋事犯罪。司法解释对涉文生视频犯罪相关罪名构成要件的规定应当既有突破也有限制。我国刑法应设立数据安全责任事故罪以追究文生视频研发者、生产者的过失罪过下的刑事责任。应及时完善生成式人工智能产品应用的前置法规定。司法实践中应将文生视频的智能化程度区分为信息的整理、信息的基本加工、信息的深度加工三类,以此合理分配使用者、研发者与生产者所应当承担的涉文生视频犯罪的刑事责任。 展开更多
关键词 文生视频(Sora) 文生视频 生成内容 法益 数据安全责任事故罪
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决策树码率自适应算法的无数据蒸馏框架 被引量:1
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作者 黄天驰 李朝阳 +2 位作者 张睿霄 李文哲 孙立峰 《计算机学报》 EI CAS CSCD 北大核心 2024年第1期113-130,共18页
码率自适应(Adaptive Bit-Rate,ABR)算法是流媒体视频传输中至关重要的技术.该算法根据当前网络情况和播放状态等因素,为下一个视频块选择合适的码率,以确保用户获得良好的体验质量(QoE).其中,基于学习的ABR算法因其不依赖传统模型和从... 码率自适应(Adaptive Bit-Rate,ABR)算法是流媒体视频传输中至关重要的技术.该算法根据当前网络情况和播放状态等因素,为下一个视频块选择合适的码率,以确保用户获得良好的体验质量(QoE).其中,基于学习的ABR算法因其不依赖传统模型和从头学习策略的特点,表现出良好的性能,并逐渐取代需要繁琐调优的启发式ABR算法,成为研究领域的热点.然而,这些算法使用神经网络推理,导致模型参数较多,整体计算量较大,使得在实际场景中难以部署.因此,以往的研究提出了决策树蒸馏方案,即使用轻量级的决策树来提取基于学习的ABR算法的专家策略,并在线上部署这些决策树.然而,本文的实验结果表明,过去的蒸馏框架忽略了训练环境对蒸馏后策略的影响,导致策略的泛化能力较差.因此,本文提出了一种名为NIA(data-free Network-environmental Imitationbased rate Adaptation framework)的新型无数据蒸馏框架,用于生成具有更好泛化性能的决策树A BR算法.NIA通过网络环境生成模块构建多个人工网络环境,并在每次迭代训练前使用环境选择模块来选择适合的网络场景,然后与该场景进行交互,利用基于学生驱动的模仿学习算法完成决策树的蒸馏过程.本文还设计了完整的评测平台测试NIA的性能.实验表明,NIA在各种带宽数据集上展现出良好的QoE性能和泛化性能:(1)相较于启发式算法,在QoE指标上提升了1%~46%;(2)与以往的决策树蒸馏方案相比,在低带宽场景下表现相当,但在高带宽场景下提升了近1倍;(3)总体性能接近甚至超过基于学习的算法(即专家策略)的表现. 展开更多
关键词 流媒体 码率自适应算法 无数据蒸馏
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车路协同感知技术研究进展及展望 被引量:2
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作者 伊笑莹 芮一康 +2 位作者 冉斌 罗开杰 孙虎成 《中国工程科学》 CSCD 北大核心 2024年第1期178-189,共12页
近年来,我国自动驾驶研究逐步从聚焦于单车智能技术向车路协同技术转变,为智能交通产业发展带来了重大机遇;我国在车路协同感知领域的研究虽处于起步阶段,但注重技术推动,未来发展前景广阔。本文致力于深入探讨车路协同感知技术的发展动... 近年来,我国自动驾驶研究逐步从聚焦于单车智能技术向车路协同技术转变,为智能交通产业发展带来了重大机遇;我国在车路协同感知领域的研究虽处于起步阶段,但注重技术推动,未来发展前景广阔。本文致力于深入探讨车路协同感知技术的发展动态,梳理了车路协同感知基础支撑技术的特性和发展现状,厘清了车路协同感知技术的研究进展,探讨了其技术发展趋势,并针对推动车路协同感知技术发展提出了一系列建议。研究表明,车路协同感知技术正朝着多源数据融合方向发展,主要集中在纯视觉协同感知技术优化、激光雷达点云处理技术升级、多传感器时空信息匹配与数据融合技术发展以及车路协同感知技术标准体系构建等方面。为进一步促进我国车路协同自动驾驶产业的迅速成长,研究建议,加大对多模态车路协同感知技术的研发投入、深化行业间的合作、制定统一的感知数据处理技术标准并加速技术应用普及,以期推动我国在全球自动驾驶竞争中赢得主动,推动自动驾驶行业稳定持续发展。 展开更多
关键词 自动驾驶 车路协同感知 多源数据 激光雷达 视频摄像机 标准体系
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基于多模态知识主动学习的视频问答方案
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作者 刘明阳 王若梅 +1 位作者 周凡 林格 《计算机研究与发展》 EI CSCD 北大核心 2024年第4期889-902,共14页
视频问答是人工智能领域的一个热点研究问题.现有方法在特征提取方面缺乏针对视觉目标运动细节的获取,从而会导致错误因果关系的建立.此外,在数据融合与推理过程中,现有方法缺乏有效的主动学习能力,难以获取特征提取之外的先验知识,影... 视频问答是人工智能领域的一个热点研究问题.现有方法在特征提取方面缺乏针对视觉目标运动细节的获取,从而会导致错误因果关系的建立.此外,在数据融合与推理过程中,现有方法缺乏有效的主动学习能力,难以获取特征提取之外的先验知识,影响了模型对多模态内容的深度理解.针对这些问题,首先,设计了一种显性多模态特征提取模块,通过获取图像序列中视觉目标的语义关联以及与周围环境的动态关系来建立每个视觉目标的运动轨迹.进一步通过动态内容对静态内容的补充,为数据融合与推理提供了更加精准的视频特征表达.其次,提出了知识自增强多模态数据融合与推理模型,实现了多模态信息理解的自我完善和逻辑思维聚焦,增强了对多模态特征的深度理解,减少了对先验知识的依赖.最后,提出了一种基于多模态知识主动学习的视频问答方案.实验结果表明,该方案的性能优于现有最先进的视频问答算法,大量的消融和可视化实验也验证了方案的合理性. 展开更多
关键词 视频问答 数据融合与推理 多模态主动学习 视频细节描述提取 深度学习
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基于VideoCharger视频点播系统的设计与实现 被引量:2
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作者 朱友芹 陈圣琳 王欣 《计算机应用》 CSCD 北大核心 2001年第1期16-19,共4页
探讨了VideoCharger的逻辑组成、交互与配置方式 ,及详细的资源需求分析 ,给出了据此建立VOD系统的系列解决方案。
关键词 视频计算机系统 逻辑结构 视频点播 数据泵 图像处理
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