基于亮度补偿算法的显示子系统低功耗的设计

低功耗设计是嵌入式系统的一个重要课题,显示系统的功耗在整个系统功耗占有很大比例,降低显示系统功耗成为嵌入式低功耗设计的重中之重。设计基于WindowsMobile操作系统、PXA270处理器,以标准亮度补偿算法为基础,动态降低背光电流以节省功耗,同时相应的调整LCD屏的光透过率,以补偿背光亮度降低带来的图像亮度降低,在人眼可接受的失真范围内,实现了系统功耗的降低。整个设计在驱动层实现,功能稳定,有很好的可移植性。     

动态控制的LED背光源设计

以往因CCFL亮度的不可控性,液晶电视是采用调节LCD的控制电压,改变液晶的透过率,来实现对LCD总体亮度的控制,这种方式在很多情况下造成背光模组的光能和电能浪费。而采用亮度动态控制的方式可以很方便地通过调节LED背光源电源的电压或输入电流的大小,从而改变LED的发光强度的方案,可使电视在LED较低能耗条件下工作。亮度动态控制就是通过对显示的画面进行分析,得到不同区域的最佳亮度同时控制LED背光达到相应的亮度。     

Saliency-based framework for facial expression recognition

This article proposes a novel framework for the recognition of six universal facial expressions. The framework is based on three sets of features extracted from a face image: entropy, brightness, and local binary pattern. First, saliency maps are obtained using the state-of-the-art saliency detection algorithm “frequency-tuned salient region detection”. The idea is to use saliency maps to determine appropriate weights or values for the extracted features (i.e., brightness and entropy).We have performed a visual experiment to validate the performance of the saliency detection algorithm against the human visual system. Eye movements of 15 subjects were recorded using an eye-tracker in free-viewing conditions while they watched a collection of 54 videos selected from the Cohn-Kanade facial expression database. The results of the visual experiment demonstrated that the obtained saliency maps are consistent with the data on human fixations. Finally, the performance of the proposed framework is demonstrated via satisfactory classification results achieved with the Cohn-Kanade database, FG-NET FEED database, and Dartmouth database of children’s faces.     

生石灰对碱回收白泥物性影响

研究生石灰对白泥基本性能的影响。结果表明,生石灰对白泥白度的影响比较显著,在生石灰添加比例从100%降至0%时,绿液作为碳酸根源,白泥白度值从76.44%ISO增至90.11%ISO,增幅为17.88%;生石灰有利沉降体积的增加,但对堆积密度存在负面影响;另外,生石灰对白泥的粒径影响也较明显,当生石灰添加比例从100%减至20%时,其中位径从5.73μm减小到4.88μm。     

沙柳P-RC APMP制浆工艺条件的研究

研究了沙柳P—RC APMP浆料性能的影响因素,并且从沙柳成浆后的纸浆白度,光学性能和纸浆强度出发,提出了沙柳P-P．CAPMP浆适合的化学预处理工艺条件。沙柳P—RcAPMP浆采用的化学预处理条件：NaOH用量8％、H2O2用量10％、处理温度60℃、时间40min、液比1：4,此时纸浆的白度和物理强度最佳,得率较高。纸浆得率75．78%,白度74．16％ ISO,不透明度86．25％,光散射系数42．84m2／kg,裂断长5．62km,撕裂指数3．30mN·m2／g,耐破指数1．42kPa．m2／g。     

现场总线型交通信号灯组的设计与实现

讨论一种新型的总线型智能交通信号灯组的设计与实现技术.     

基于陶器刻划符号的智能特征图形设计

目的 为了充分挖掘陶器刻划符号所蕴含的文化价值和美学价值,通过提取陶器刻划符号的图像特征并将其应用于智能终端产品的图形界面设计,来推动传统刻划图形在智能信息环境下的应用、传承与发展.方法 在陶器刻划符号图像亮度特征处理的基础之上,提出了基于卷积运算的图像亮度特征提取模型,以及动态特征图形的创建方法,并以双墩刻划符号为例,开展了基于亮度特征提取模型的智能特征的图形设计与应用实践.结果 研究与实践结果表明,图像亮度特征处理大大简化了图像特征的提取过程,而卷积运算提升了图像特征的提取精度,因此在此基础之上进行的智能特征图形设计精准而高效.结论 该方法实现了传统刻划图形的图像特征的有效提取与智能特征的图形设计,可应用于智慧博物、智慧旅游等智能终端产品的图形界面设计与展示.通过智能图形技术和产品应用形式来有效传达传统刻划图形的图像特征、文化内涵和美学价值.     

Brightness preserving bi‐level fuzzy histogram equalization for MRI brain image contrast enhancement

In this article, brightness preserving bi‐level fuzzy histogram equalization (BPFHE) is proposed for the contrast enhancement of MRI brain images. Histogram equalization (HE) is widely used for improving the contrast in digital images. As a result, such image creates side‐effects such as washed‐out appearance and false contouring due to the significant change in brightness. In order to overcome these problems, mean brightness preserving HE based techniques have been proposed. Generally, these methods partition the histogram of the original image into sub histograms and then independently equalize each sub‐histogram. The BPFHE consists of two stages. First, fuzzy histogram is computed based on fuzzy set theory to handle the inexactness of gray level values in a better way compared to classical crisp histograms. In the second stage, the fuzzy histogram is divided into two sub‐histograms based on the mean intensities of the multi‐peaks in the original image and then equalizes them independently to preserve image brightness. The quantitative and subjective enhancement of proposed BPBFHE algorithm is evaluated using two well known parameters like entropy or average information contents (AIC) and Feature Similarity Index Matrix (FSIM) for different gray scale images. The proposed method have been tested using several images and gives better visual quality as compared to the conventional methods. The simulation results show that the proposed method has better performance than the existing methods, and preserve the original brightness quite well, so that it is possible to be utilized in medical image diagnosis.     

基于自适应吸引半径的萤火虫算法的粒子滤波

针对粒子滤波算法对粒子数目的大量需求等弊端,提出一种基于改进的萤火虫算法的粒子滤波。首先,在萤火虫的亮度公式中引入观测值信息以提高算法跟踪的准确性;其次,提出自适应吸引半径参数来控制萤火虫群寻优时的吸引范围,使算法的实时性更好;最终利用萤火虫算法的迭代寻优来进行粒子更新。对比实验表明,该算法在跟踪精度和运行时间上都有所优化,说明该算法即使在粒子数目较少的条件下也能保证目标跟踪的准确性和实时性。     

VIIRS中波红外地表双向反射率反演算法研究

中波红外(mid-infrared,MIR)是目前地球观测中热点研究的光谱区域,相比于可见光具有很多优势。中波红外反射率在叶生物量估算、不同植被类型区分等方面得到了广泛的应用。但由于在白天时卫星传感器接收到的辐射能量存在反射与发射能量耦合的问题,使得中波红外数据的利用存在一些困难。本文通过类似劈窗技术的计算模型计算出无太阳辐射时地表亮温T0g,并结合中波红外辐射传输模型推导出了适用于VIIRS中波红外地表双向反射率的反演模型。结果表明：反射率理论反演值与实际值较吻合,在太阳天顶角为0°时RMSE仅为0.009;反演模型受气象因子和仪器噪声的影响很小,在实际应用中可以忽略。