win7VS2013OpenCV2.4.9 一、cvSmooth函数用法 译自OpenCV2.4.7,篇末有附录 定义原型 span style=font-size:14px;void cvSmooth(const CvArr* src,//输入图像CvArr* dst,//输出图像,一般大小和src相同int smoothtype=CV_GAUSSIAN,// 平滑方式int size1=3,//
win7+VS2013+OpenCV2.4.9
一、cvSmooth函数用法
译自OpenCV2.4.7,篇末有附录
定义原型
<span style="font-size:14px;">void cvSmooth( const CvArr* src,//输入图像 CvArr* dst,//输出图像,一般大小和src相同 int smoothtype=CV_GAUSSIAN,// 平滑方式 int size1=3,//平滑窗口的宽度 int size2=0,//平滑窗口的长度 double sigma1=0,// double sigma2=0// );</span>
参数说明:
src-输入图像.
dst-输出图像.
smoothtype-平滑方法:
CV_BLUR_NO_SCALE(简单不带尺度变换的模糊) - -对每个象素的size1×size2 领域求和。
如果邻域大小是变化的,可以事先利用函数 cvIntegral 计算积分图像。
CV_BLUR (simple blur)- -对每个象素param1×param2邻域求和并做尺度变换 1/(size1×size2)。
CV_GAUSSIAN(gaussian blur) - -对图像进行核大小为size1×size2 的高斯卷积。
CV_MEDIAN(median blur) - -对图像进行核大小为size1×size1 的中值滤波 (邻域是方的)。
CV_BILATERAL(双向滤波) - -应用双向 size1×size1滤波,彩色 sigma=sigma1,空间 sigma=sigma2.。
关于双向滤波,可参考http://www.dai.ed.ac.uk/CVonline/LOCAL_COPIES/MANDUCHI1/Bilateral_Filtering.html。
size1-平滑操作的第一个参数,平滑窗口的宽度。必须是正奇数(1,3,5,...)
size2-平滑操作的第二个参数,平滑窗口的高度。CV_MEDIAN和CV_BILATERAL模式无视之。
在其他三种模式下,如果size2被设置为默认值0,那么程序会自动将size2设为size1。否则size2必须为正奇数。
sigma1-对应高斯参数的 Gaussian sigma (标准差). 如果为零,则标准差由下面的核尺寸计算:
sigma = (n/2 - 1)*0.3 + 0.8, 其中 n=size1 对应水平核,n=size2 对应垂直核.
对小的卷积核 (3×3 to 7×7) 使用如上公式所示的标准 sigma 速度会快。
如果sigma1 不为零,而 size1 和 size2 为零,则核大小由sigma 计算 (以保证足够精确的操作).
sigma2-OpenCV2.4.7文档中未说明,Learning OpenCV 中解释为不对称高斯核垂直方向的sigma,而水平方向simga为sigma1
函数 cvSmooth 可使用上面任何一种方法平滑图像。每一种方法都有自己的特点以及局限:
1、 没有缩放的图像平滑仅支持单通道图像,并且支持8位到16位的转换(与cvSobel和cvLaplace相似)和32位浮点数到32位浮点数的变换格式。
2、简单模糊和高斯模糊支持 1- 或 3-通道, 8-比特 和 32-比特 浮点图像。这两种方法可以(in-place)方式处理图像。
3、中值和双向滤波工作于 1- 或 3-通道, 8-位图像,但是不能以 in-place 方式处理图像.
注意:此函数现被弃用。使用 GaussianBlur() , blur() , medianBlur() 或者 bilateralFilter()
二、说明例程:
#include<cv.h> #include<highgui.h> #include<stdio.h> int main(int argc,char** argv) { //check argin if(argc<br> 运行效果: <p> <img src="/inc/test.jsp?url=http%3A%2F%2Fimg.blog.csdn.net%2F20141106220914576%3Fwatermark%2F2%2Ftext%2FaHR0cDovL2Jsb2cuY3Nkbi5uZXQvZnVsbF9zcGVlZF90dXJibw%3D%3D%2Ffont%2F5a6L5L2T%2Ffontsize%2F400%2Ffill%2FI0JBQkFCMA%3D%3D%2Fdissolve%2F70%2Fgravity%2FSouthEast&refer=http%3A%2F%2Fblog.csdn.net%2Ffull_speed_turbo%2Farticle%2Fdetails%2F40868573" alt="Learning OpenCV 2.4.9 图像平滑 cvSmooth" ><br> </p> <p> *篇幅有限,只贴了<span>CV_BLUR</span></p> <p> <span>三、附录</span></p> <p> OpenCV 2.4.7.0 手册</p> <p> <span><strong>src </strong></span><span>– The source image<br> <span>dst <span>– The destination image<br> <span>smoothtype <span>– Type of the smoothing:<br> <span>– CV_BLUR_NO_SCALE <span>linear convolution with <span>size1 <span><em>× </em><span>size2 <span>box kernel (all 1’s).<br> <span>If you want to smooth different pixels with different-size box kernels, you can use the<br> <span>integral image that is computed using <span>integral()<br> <span>– CV_BLUR <span>linear convolution with <span>size1 <span><em>× </em><span>size2 <span>box kernel (all 1’s) with subsequent<br> <span>scaling by <span>1/<span>(<span>size1 <span><em>· </em><span>size2<span>)<br> <span>– CV_GAUSSIAN <span>linear convolution with a <span>size1 <span><em>× </em><span>size2 <span>Gaussian kernel<br> <span>– CV_MEDIAN <span>median filter with a <span>size1 <span><em>× </em><span>size1 <span>square aperture<br> <span>– CV_BILATERAL <span>bilateral filter with a <span>size1 <span><em>× </em><span>size1 <span>square aperture, color sigma=<br> <span>sigma1 <span>and spatial sigma= <span>sigma2 <span>. If <span>size1=0 <span>, the aperture square side is set<br> <span>to <span>cvRound(sigma2*1.5) *2+1 <span>. Information about bilateral filtering can be found at<br> <span>http://www.dai.ed.ac.uk/CVonline/LOCAL_COPIES/MANDUCHI1/Bilateral_Filtering.html<br> <span>size1 <span>– The first parameter of the smoothing operation, the aperture width. Must be a positive odd number (1, 3, 5, ...)<br> <span>size2 <span>– The second parameter of the smoothing operation, the aperture height. Ignored<br> <span>by <span>CV_MEDIAN <span>and <span>CV_BILATERAL <span>methods. In the case of simple scaled/non-scaled and<br> <span>Gaussian blur if <span>size2 <span>is zero, it is set to <span>size1 <span>. Otherwise it must be a positive odd<br> <span>number.<br> <span>sigma1 <span>– In the case of a Gaussian parameter this parameter may specify Gaussian <span>σ <span>(standard deviation). If it is zero, it is calculated from the kernel size:<br> <span>σ <span>= <span>0.3<span>(<span>n/2 <span>? <span>1<span>) + <span>0.8 <span>where <span>n <span>= <span>size1 <span>for horizontal kernel<br> <span>size2 <span>for vertical kernel<br> <span>3.1. Imag e Filtering 263<br> <span>The OpenCV Reference Manual, Release 2.4.7.0<br> <span>Using standard sigma for small kernels ( <span>3 <span><em>× </em><span>3 <span>to <span>7 <span><em>× </em><span>7 <span>) gives better speed. If <span>sigma1 <span>is<br> <span>not zero, while <span>size1 <span>and <span>size2 <span>are zeros, the kernel size is calculated from the sigma (to<br> <span>provide accurate enough operation).<br> <span>The function smooths an image using one of several methods. Every of the methods has some features and restrictions<br> <span>listed below:<br> <span>? Blur with no scaling works with single-channel images only and supports accumulation of 8-bit to 16-bit format<br> <span>(similar to <span>Sobel() <span>and <span>Laplacian() <span>) and 32-bit floating point to 32-bit floating-point format.<br> <span>? Simple blur and Gaussian blur support 1- or 3-channel, 8-bit and 32-bit floating point images. These two<br> <span>methods can process images in-place.<br> <span>? Median and bilateral filters work with 1- or 3-channel 8-bit images and can not process images in-place.<br> <span>Note: <span>The function is now obsolete. Use <span>GaussianBlur() <span>, <span>blur() <span>, <span>medianBlur() <span>or <span>bilateralFilter() <span>.</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><br> </span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><br> </p> <p><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><span><br> </span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></p> </stdio.h></highgui.h></cv.h>