Multitarget Detection Using a Circular Harmonic Joint Wavelet Transform Correlator with Power Spectrum Subtraction

将小波变换与圆谐联合变换相关器相结合，应用功率谱相减技术进行多目标检测，可以从输出面上直接看出系统对真目标的旋转不变检测及识别假目标的能力。分析和量化了输入景物噪声对结果的影响。计算机模拟实验表明这种方法明显改善了普通圆谐联合变换相关器的性能，具有良好的相关输出性能和抗噪声能力。A method of multitarget detection is presented.It combines circular harmonic joint transform correlator (CHJTC ) with wavelet transform, and introduces power spectrum subtraction technique.Using this method we can find out directly the rotation-invariant recognition for the real pattern and the discrimination performance relative to the false pattern.The effect on the result of noise in the input scene is analyzed and quantified.Computer simulation verifies that it can enhance obviously the performance of general CHJTC, and yield a better correlation output and higher capability of anti-background noise

Phase Modulated Real Time Joint TransForm Correlator

提出一种位相调制的实时联合变换相关器。它采用液晶显示屏作为输入器件，用液晶光阀记录和显示联合功率谱。利用液晶显示屏上的光栅状结构的衍射级，提高光能的利用率，并充分利用液晶光阀的有效使用面积。采用成像透镜放大各衍射级的联合频谱，适应液晶光阀较低的分辨率要求。在相关器的光路中插入两块倾斜的平行平面玻璃板，以改变各衍射级的参考图像和目标图像之间的位相差。这种方法可产生比传统的实时联合变换相关器更好的输出相关性能。实验结果证实了该系统设计及性能分析的正确性A phase modulated real time joint transForm correlator is proposed, in which a liquid crystal display screen is adopted as an input device and the joint power spectrum is recorded and displayed by a liquid crystal light valve.The diFFraction orders of the grating type structure on the liquid crystal display screen are utilized in this system.As a result, it can use the light energy as well as the physical area of the liquid crystal light valve more eFFiciently.In order to suit low resolution of the liquid crystal light valve, an imaging lens is applied to ampliFying joint Frequency spectrum of the diFFraction orders.The two oblique parallel plane glass plates are inserted in the correlator to manipulate the phase diFFerences between the reFerence image and the target image of the diFFraction orders.This technique yields better output correlation perFormences than the classical real time joint transForm correlator.The experimental results veriFied the correctness of the system design and perFormance analysis.福建省自然科学基

Multitarget Detection Using a High-eFFiciency Hybrid Optical Joint TransForm Correlator

提出一种使用高效光电混合的联合变换相关器作多目标检测的方法。这一方法将联台功率谱复制n份构成n个全同的联合功率谱列阵，可以更有效地利用空间光调制器的面积以及读出无效率，因而在输出面可获得增强的光学相关信号。The technique For multitarget detection using a high-eFFiciency hybrid optical joint transForm correlator is proposed.In this technique, N copies of the joint power spectrum are made and N identical joint power spectral array is constructed.This technique can eFFectively make use of the areas of the spatial light modulator as well as the eFFiciency of the read out light, so that an enhanced optical correlation signal can be obtained at the output plane

Rotation invariant Target Detection by Using a Modified Fringe adjusted Circular Harmonic Joint Transform Correlator

提出一种修正条纹调节的圆谐联合变换相关器作旋转不变的目标检测的方法.在这种方法中，参考图像（即圆谐展开分量的实部和虚部）、圆盘状的局部偏置函数以及目标图像同时显示于输入面.这一方法对联合功率谱作了修正，先将联合功率谱减去纯输入景物（含局部偏置函数）的功率谱和参考图象（含局部偏置函数）的功率谱，再加上局部偏置函数的功率谱，然后将所得修正的联合功率谱乘以条纹调节滤波函数.它能产生比普通的圆谐联合变换相关器更好的相关输出.给出计算机模拟结果.Rotation invariant target detection by using a modified fringe adjusted circular harmonic joint transform correlator is proposed.In this technique, the reference images ( i.e.the real and imaginary parts of the circular harmonic component ), the disk like local bias function and the target image are displayed simultaneously in the input plane.The joint power spectrum is first modified by the subtraction of the power spectra of the input scene only (including local bias function) as well as of the reference image (including local bias function) and by the addition of the power spectrum of the local bias function from it.The resultant joint power spectrum modified is then multiplied by the fringe adjusted filter function.The technique is found to yield a better correlation output than that yielded by a classical circular harmonic joint transform correlator.Computer simulation results are given.集美大学水产学院青年专项科研基

Digital Reconstruction of Holographic Interference

本文报告的全息干涉的数字重现方法 ,可消除像差、噪声和胶片非线性等因素的影响。用 CCD摄像机记录全息图 ,离散化的数据输入计算机。计算机的数字显示可产生较好的条纹图样和测量结果。给出了玻璃板平行度和物体表面微小转动的实验结果。A method of digital reconstruction of holographic interference is described.It can eliminate aberrations,noise,and film nonlinearity etc.The hologram is recorded by a CCD camera,and the discrete data are sent to the computer.The numerical display of the computer can yield better fringe pattern and measurement results.Experimental results for glass plate parallelism and small rotation of object surface are given.福建省教委科技项

Circular Harmonic Joint Transform Correlator Based on Wavelat Transform

将小波变换应用于圆谐联合变换相关器作旋转不变的目标检测．与高通滤波的圆谐联合变换相关器相比，其输出相关峰宽度、识别力、峰噪比和旋转不变性都有较大改善．小波函数采用改进的Ｍｅｘｉｃａｎ－ｈａｔ小波，圆谐联合变换相关器采用直流偏置型．给出计算机模拟实验结果．Wavelet transform is used in the circular harmonic joint transform correlator for ratation- invariant target detection. Comparing with the high pass filtering circular harmonic joint transform correlator, its correlation peak width, discrimination ability, peak-to-noise ratio, and rotation-invariant performance are better. The modified Mexican-hat wavelet is chosen as the wavelet function and the DC bias is adopted for the circular harmonic joint transform correlator. Computer simulaton results are given

Rotation Invariant Target Detection Using a Modified Amplitude Modulated Hybrid Optical Circular Harmonic Joint Transform Correlator

提出一种修正振幅调制的光电混合圆谐联合变换相关器作旋转不变的目标检测的实验系统。参考图像（即圆谐展开分量的实部和虚部）、圆盘状的局部偏置函数以及目标图像同时显示于输入面。此方法对联合功率谱作了修正，先将联合功率谱减去纯输入景物（含局部偏置函数）的功率谱和参考图像（含局部偏置函数）的功率谱，再加上局部偏置函数的功率谱，然后将所得修正的联合功率谱乘以振幅调制滤波函数。这种方法能产生比普通的圆谐联合变换相关器更好的相关输出。给出计算机模拟结果及光电混合实验结果。Rotation invariant target detection using a modified amplitude modulated hybrid optical circular harmonic joint transform correlator is proposed.In this technique, the reference images (i.e.the real and imaginary parts of the circular harmonic component), the disk like local bias function and the target image are displayed simultaneously in the input plane.The joint power spectrum is firstly modified by the subtraction of the power spectra of the input scene only (with local bias function) as well as of the reference image (with local bias function) and by the addition of the power spectrum of the local bias function from it.Then the resultant modified joint power spectrum is multiplied by the amplitude modulated filter function.The technique is found to yield a better correlation output than a classical circular harmonic joint transform correlator does.Computer simulation results and hybrid optical experimental results are given.集美大学水产学院青年专项科研基

Multitargct Detection Using a Chirp-encoded Joint TransForm Correlator with High Pass Filtering

根据啁啾编码的原理和高通滤波的方法.提出使用啁啾编码的高通滤波的联合变换相关器作多目标检测。使用这种方法.可使所想要的参考图像和目标像之间的互相关峰与不想要的直流项、各目标图像之间的互相关峰以及谐波峰输出在不同的平面上，从而提高对多目标检测的准确度，给出对具有灰度级的多目标输入景物的计算机模拟结果。Based on the chirp-encoding and high Pass Filtering, the multitarget detectionusing a chirp-encoded joint transForm correlator with high pass Filtering is proposed.Thistechnique Focuses the desired cross correlation terms between the reFerence image and thetarget images and the undesired terms, including D.C.term, selF- correlation termsbetween the target images and various higher-order correlation terms, onto separated outputplanes.Thus it has higher accuracy of detection.Computer simulation results For the inputgray-scale multitarget scenes are given.福建省自然科学基

Multitarget Detection Using a Real time Joint TransForm Correlator with Power Spectrum Subtraction

提出一种使用功率谱相减的实时联合变换相关器作多目标检测。使用这种方法，输入面有两套联合图像。在第二套联合图像中，参考图像是对比度反转的。使用衍射光栅对这两套联合功率谱作相减处理，这种方法可大大抑制输出面的直流项及不想要的伪相关峰，增强相关峰的强度、锐度和峰噪比，提高抗噪声干扰的能力，从而提高对多目标检测的准确度。给出对具有灰度级的多目标输入景物的计算机模拟结果和光学实验结果。实验结果证实了该系统设计及性能分析的正确性。Multitarget detection using a real time joint transForm correlator with power spectrum subtraction is proposed.It has two joint images in the input plane.In the second joint image, the reFerence image is contrast reversal.The two joint power spectra are subtracted using a diFFraction grating.The D.C.term and undesired terms are substantially suppressed by this technique.It can yield strong auto correlation peak intensity, sharp auto correlation peak width, big peak to noise ratio, and the high capability of anti background noise.Thus it produces higher accuracy of detection.Computer simulation results and optical implementation For input scences of the gray scale multitarget are given.The experimental results have veriFied the correctness of the system design and perFormance analysis.福建省自然科学基

White-Light Optical InFormation Processing by Computer-Generated Holographic Filter

在白光信息处理中，利用计算机产生的全息宽带扇形空间滤波器进行图象边缘增强和消模糊处理。分析其对光源空间相干性的要求。采用一种有效利用白光光源强度的简易实验装置。给出计算机模拟结果和光学实验结果。In white-light optical inFormation processing,image edge enhancementand image debluring are operated by computer-generated holographic broad-band Fan-shapedFilter.Spatial coherence requirement is analysed.A simply-built experimental installation,which is able to use eFFectually the intensity of white-light source,is adopted.Some results ofcomputer simulation and optical experiments are given