基于音频特征的工程车辆工况识别研究

高效率地使用工程车辆是工程项目管理中节约成本的有效方法，无人监管环境下工程车辆的工况识别，是实现工程车辆高效率使用的有效手段。目前以GPS等技术为核心的车辆智能管理系统未对工程车辆进行工况识别，提出一种基于GRU循环神经网络的工程车辆工况识别方法，通过对工程车辆在不同工况下产生的音频信号进行分析，从中提取Mel倒谱系数作为主要特征，构建GRU循环神经网络模型进行训练和识别。实验结果表明，该方法可以实现对工程车辆工况的有效识别。     

Difference angle quantization index modulation scheme for image watermarking

In this paper, we propose a new angle quantization index modulation (AQIM) method, called the difference AQIM (DAQIM) method. The proposed method aims to improve the watermarking performance against gain attacks. Unlike the original AQIM method (Ourique et al., Angle QIM: a novel watermark embedding scheme robust against amplitude scaling distortions, in: Proceedings of IEEE International Conference on Acoustics, Speech, and Signal Processing, vol. 2, 2005, pp. 797–800), the DAQIM method quantizes the difference of the two angles instead of the angles themselves. The main advantage of the DAQIM method is to disperse the interference to the watermark signal from one angle to more angles. Thus, the watermark has a higher ability to resist attacks. We perform a theoretical analysis of the document-to-watermark ratio (DWR) based on our proposed method. We show that our proposed method can obtain a lower embedding distortion compared to the AQIM and the gradient direction watermarking (GDWM) (Nezhadarya et al., IEEE Trans. Inf. Forensics Secur., 6(4), 2011, 1200–1213), methods under the same robustness and payload conditions. The experimental results demonstrate that our proposed method outperforms common existing methods in terms of the robustness against various attacks such as the JPEG quantization noise, additive white Gaussian noise (AWGN), cropping effect and mean filtering.     

AoIP广播播控系统设想

本文首先回顾了广播播控系统发展的几个阶段;其次分析了本台播控系统的现状、播控系统存在的不足和缺陷;最后通过充分比对传统音频矩阵架构与AoIP架构的优缺点,提出了全新播控系统架构设想和功能设想。     

音频大地电磁法在新疆阿依拉苏铀矿勘查中的应用

阿依拉苏铀矿点具构造控矿的特征,但地表断层产状较陡,无法判断深部断层延伸情况。文章在综合地质调查的基础上,通过音频大地电磁测深,初步了解地下地质体的空间展布及断层的延伸情况。经钻探工程验证,深部存在铀矿体,最终认为地表矿点为深部含矿体错动地表所致。     

基于视觉显著模型的音视频交叉水印算法

提出一种基于Itti视觉显著模型的音视频交叉水印算法.首先利用音频码流的低通幅值特性生成水印,并嵌入到视频码流中;其次解码视频码流的关键帧Ⅰ帧,获取YUV序列上的亮度(Y)分量,并对其进行显著性分析;最后分块对非显著区域进行DCT变换,并通过量化索引调制嵌入水印.实验结果表明,该算法将嵌入水印后的关键帧平均PSRN值提高了1.678 5 dB,缓解了水印不可见性和鲁棒性的矛盾,实现了音视频码流之间的交叉保护.     

基于代价策略的H.264/AVC半脆弱水印算法

In order to solve some existing problems on detecting malicious tampering by video watermarking based on H.264/AVC video compression standard,a semi-fragile video watermarking algorithm for H.264/AVC based on cost strategy was proposed.To further improve the robustness of the feature codes in semi-fragile video watermarking algorithm,a new generation algorithm for feature codes by eliminating the correlation of them was proposed.In order to meet the requirement that the semi-fragile watermarks should be uniformly embedded into the video frames to locate the tampered region accurately,a minimal cost function was introduced to select a DCT coefficient in the 4 × 4 block residual to embed watermark which had minimal impact on the video quality and bit rates.Experimental results show that the proposed algorithm can significantly reduce impact on video quality and bit rate because of embedding the watermarking by adopting the minimum cost function and it is sensitive to malicious manipulations.The retrieved feature code and watermarking can detect and locate malicious manipulations.     

基于音频控制电路测试中PLC技术和模拟测试系统的应用

传统的音频控制电路测试所采用的系统是一种数模混合测试,此系统涉及模拟信号测试与数字信号测试两个方面,频率覆盖了从Hz到上GHz的范围,但缺乏结构化的可测试性设计,测试时间长也较为昂贵。本文研究引入全新的音频控制电路测试方案,是基于单片机的基础上,利用单片机功能强、集成度高、可靠性高及编程开发灵活等特点,并采用PLC技术和模拟测试系统等方式测试音频控制电路,进一步加深了对模拟电路测试系统的利用率。     

基于ITIL框架的面向视听新媒体运行维护指标体系研究

视听新媒体运行维护指标体系作为视听新媒体系统的重要组成和支撑部分,对于提高视听新媒体运行维护管理水平具有重要意义。在当前条件下应不断完善。本文参考ITIL的成熟实践经验,结合视听新媒体的技术特性,系统论述了构建该体系的背景、思路、主要内容、注意事项,希望能给相关运维团队提供技术建议。     

基于FPGA实现的PCI-I2S接口转换电路

提出了一种基于FPGA实现的PCI-I2S音频系统方法。通过在FPGA中将PCI软核、FIFO以及设计的接口电路等相结合,在FPGA上实现了PCI、I2C、I2S等多种总线,并且结合音频解码器实现了不同采样频率语音数据的传输以及播放功能。系统充分利用FPGA的片上资源及其可编程特性,减少了硬件电路的复杂度