edge_dtection

1 SIFT 发展历程 SIFT算法由D.G.Lowe 1999年提出，2004年完善总结。后来Y.Ke将其描述子部分用PCA代替直方图的方式，对其进行改进。 2 SIFT 主要思想 SIFT算法是一种提取局部特征的算法，在尺度空间寻找极值点，提取位置，尺度，旋转不变量。 3 SIFT算法的主要特点： a) SIFT特征是图像的局部特征，其对旋转、尺度缩放、亮度变化保持不变性，对视角变化、仿射变换、噪声也保持一定程度的稳定性。 b) 独特性(Distinctiveness)好，信息量丰富，适用于在海量特征数据库中进行快速、准确的匹配[23]。 c) 多量性，即使少数的几个物体也可以产生大量SIFT特征向量。 d) 高速性，经优化的SIFT匹配算法甚至可以达到实时的要求。 e) 可扩展性，可以很方便的与其他形式的特征向量进行联合。 4 SIFT算法步骤： 1） 检测尺度空间极值点 2） 精确定位极值点 3） 为每个关键点指定方向参数 4） 关键点描述子的生成 本包内容为sift算法matlab源码(1 SIFT course of development SIFT algorithm by DGLowe in 1999, the perfect summary of 2004. Later Y.Ke its description of the sub-part of the histogram with PCA instead of its improvement. 2 the SIFT main idea The SIFT algorithm is an algorithm to extract local features in scale space to find the extreme point of the extraction location, scale, rotation invariant. 3 the main features of the SIFT algorithm: a) SIFT feature is the local characteristics of the image, zoom, rotate, scale, brightness change to maintain invariance, the perspective changes, affine transformation, the noise also maintain a certain degree of stability. b) unique (Distinctiveness), informative, and mass characteristics database for fast, accurate matching [23]. c) large amounts, even if a handful of objects can also produce a large number of SIFT feature vectors. d) high-speed and optimized SIFT matching algorithm can even achieve real-time requirements. e) The scalability can be very convenient fe)

说明：  自己写的isodata和C均值matlab程序，文件带注释，简单易懂(Wrote it myself isodata and C mean matlab programs, files with comments, easy to understand)

中值滤波快速算法，对搜索框的排序进行归并排序，并利用前一个已排好的结果(Fast median filtering algorithm)

如题，时间序列分析相关matlab程序代码，应该比较全了(Relevant matlab code such as the title, time series analysis, all)

matlab源程序，可以仿真出来经典的BA无标度网络模型(Matlab source, can be simulated classic BA scale-free network model)

线性卷积要求两个输人序列具有持续时间，但在实际应用中，可能遇到输人序列具有无限持续时间的情况。在这种情况下，分段卷积是一种有效的解决方案。文章讨论了计算分段卷积的两种方法。仿真试验表明，分段卷积方法正确且高效。(The linear convolution needs two finite-time input sequences, but in the actual application, two infi- nite-time input sequences are possible. Under this kind of situation, the partition convolution is an effective solu- tion. In this paper, two methods of the partition convolution are discussed. The simulation experiment indicatesthat the partition convolution is correct and effective.)

说明：  使用Matlab实现的一个图像Warping的算法，通过指定需要进行Warping的点以及操作之后的位置，对图片进行扭曲变形，是图形图像处理的经典算法。(Implemented using the Matlab image Warping algorithm, Warping by specifying the need for operation after the point and the location of the distortion of the picture is the classic graphic image processing algorithms.)

说明：  Matlab实现的数字调制算法源代码(ASK, OOK, BPSK, QPSK, 8PSK)(Matlab implementation of the digital modulation algorithm source code (ASK, OOK, BPSK, QPSK, 8PSK))

Source code for MULTIPLE RADAR PULSE COMPRESSION: barker, frank, costas, polyphase(P1--> P4), polytime (T1--> T4), Linear Frequency Modulation (LFM). CHECKED & WORKED for me

根据书面协议的代码是3GPP LTE速率匹配的代码。该代码包含速率匹配交织在一起，重要的内容有点熟。(The code is on LTE 3GPP rate matching code based on written agreement. The code contains a rate matching intertwined, important content bit cropping.)