学习OpenCV3：第3章了解OpenCV的数据类型

桃扇骨 2023-02-24 03:52 10阅读 0赞

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# 1、OpenCV的数据类型 #

1.  根据组织结构，OpenCV的数据类型主页分成三类：**直接从C=++原语中继承的基本数据类型**，如int、float、数组、矩阵等；**辅助对象**，如垃圾收集指针类、用于数据切片的范围对象、抽象的终止条件等；**大型数组类型**，如cv::Mat、cv::SparseMat。
2.  基本数据类型：**cv::Point、cv::Size、cv::Rect、cv::RotateRect、固定矩形类cv::Matx、固定向量类cv::Vec、cv::Scalar**。
3.  访问成员：cv::Point、cv::Size、cv::Rect、cv::RotateRect通过**变量名**访问，如p.x、p.y等；固定向量类cv::Vec、cv::Scalar、固定矩形类cv::Matx通过**下标**访问，如myvec\[0\]、myscalar\[2\]。
4.  类型别名中的原语：**b（unsigned int）、w（unsigned short int）、s（short int）、i（int）、f（float）、d（double）**。

# 2、基本数据类型 #

<table> 
 <thead> 
  <tr> 
   <th align="left">基本数据类型</th> 
   <th align="left">别名格式</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">cv::Point</td> 
   <td align="left"><code>cv::Point{2,3}{i,f,d}</code></td> 
  </tr> 
  <tr> 
   <td align="left">cv::Size</td> 
   <td align="left"><code>cv::Size2{i,f}</code></td> 
  </tr> 
  <tr> 
   <td align="left">cv::Rect</td> 
   <td align="left"><code>cv::Rect</code></td> 
  </tr> 
  <tr> 
   <td align="left">cv::RotateRect</td> 
   <td align="left"><code>cv::RotateRect</code></td> 
  </tr> 
  <tr> 
   <td align="left">cv::Complex</td> 
   <td align="left"><code>cv::Complex{f,d}</code></td> 
  </tr> 
  <tr> 
   <td align="left">cv::Matx</td> 
   <td align="left"><code>cv::Matx{1,2,3,4,6}{f,d}</code></td> 
  </tr> 
  <tr> 
   <td align="left">cv::Vec</td> 
   <td align="left"><code>cv::cv::Vec{2,3,4,6}{b,s,w,i,f,d}</code></td> 
  </tr> 
  <tr> 
   <td align="left">cv::Scalar</td> 
   <td align="left"><code>cv::Scalar</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Point类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::Point2i p</code><br><code>cv::Point3i p</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::Point3f p2(p1)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Pointf2i p(x0,x1)</code><br><code>cv::Pointf3d p(x0,x1,x2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">构造成固定向量类</td> 
   <td align="left"><code>(cv::Vec3f) p</code></td> 
  </tr> 
  <tr> 
   <td align="left">成员访问</td> 
   <td align="left"><code>p.x p.y p.z</code></td> 
  </tr> 
  <tr> 
   <td align="left">点乘</td> 
   <td align="left"><code>float x = p1.dot(p2)</code><br><code>double x = p1.ddot(p2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">叉乘</td> 
   <td align="left"><code>p1.cross(p2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">判断一个点是否在矩形r内</td> 
   <td align="left"><code>p.inside(r)</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Size类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::Size sz</code><br><code>cv::Size2i sz</code><br><code>cv::Size2f sz</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::Size sz2(sz1)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Size2f sz(w,h)</code></td> 
  </tr> 
  <tr> 
   <td align="left">成员访问</td> 
   <td align="left"><code>sz.width sz.height</code></td> 
  </tr> 
  <tr> 
   <td align="left">计算面积</td> 
   <td align="left"><code>sz.area()</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Rect类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::Rect r</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::Rect r2(r1)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Rect r(x,y,w,h)</code></td> 
  </tr> 
  <tr> 
   <td align="left">由起始点和大小构造</td> 
   <td align="left"><code>cv::Rect r(p,sz)</code></td> 
  </tr> 
  <tr> 
   <td align="left">由两个对角构造</td> 
   <td align="left"><code>cv::Rect r(p1,p2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">成员访问</td> 
   <td align="left"><code>r.x r.y r.width r.height</code></td> 
  </tr> 
  <tr> 
   <td align="left">计算面积</td> 
   <td align="left"><code>r.area()</code></td> 
  </tr> 
  <tr> 
   <td align="left">提取左上角</td> 
   <td align="left"><code>r.tl()</code></td> 
  </tr> 
  <tr> 
   <td align="left">提取右下角</td> 
   <td align="left"><code>r.bl()</code></td> 
  </tr> 
  <tr> 
   <td align="left">判断点p是否在矩形r内</td> 
   <td align="left"><code>r.contains(p)</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Rect类的覆写操作符</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">矩形r1和矩形r2的交集</td> 
   <td align="left"><code>cv::Rect r3 = r1 &amp; r2</code><br><code>r1 &amp;= r2</code></td> 
  </tr> 
  <tr> 
   <td align="left">同时包含矩形r1和矩形r2的最小面积矩形</td> 
   <td align="left"><code>cv::Rect r3 = r1 \| r2</code><br><code>r1 \|= r2</code></td> 
  </tr> 
  <tr> 
   <td align="left">矩形r平移x</td> 
   <td align="left"><code>cv::Rect r2 = r1 + x</code><br><code>r1 += x</code></td> 
  </tr> 
  <tr> 
   <td align="left">矩形r扩大s</td> 
   <td align="left"><code>cv::Rect r2 = r1 + s</code><br><code>r1 += s</code></td> 
  </tr> 
  <tr> 
   <td align="left">比较矩形r1和矩形r2是否相等</td> 
   <td align="left"><code>bool eq = (r1 == r2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">比较矩形r1和矩形r2是否不相等</td> 
   <td align="left"><code>bool ne = (r1 != r2)</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::RotateRect类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::RotateRect rr()</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::RotateRect rr2(rr1)</code></td> 
  </tr> 
  <tr> 
   <td align="left">由两个点构造</td> 
   <td align="left"><code>cv::RotateRect rr(p1,p2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Rect rr(p,sz,theta)</code></td> 
  </tr> 
  <tr> 
   <td align="left">成员访问</td> 
   <td align="left"><code>rr.center rr.size rr.angle</code></td> 
  </tr> 
  <tr> 
   <td align="left">返回四个角的列表</td> 
   <td align="left"><code>rr.points(pts[4])</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Complex类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::Complex z1</code><br><code>cv::Complexd z2</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::Complex z2(z1)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Complexd z(re)</code><br><code>cv::Complexd z(re,im)</code></td> 
  </tr> 
  <tr> 
   <td align="left">成员访问</td> 
   <td align="left"><code>z.re z.im</code></td> 
  </tr> 
  <tr> 
   <td align="left">复共轭</td> 
   <td align="left"><code>z2 = z1.conj()</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Matx类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::Matx33f m33f</code><br><code>cv::Matx43d m43d</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::Matx22d m22d(n22d)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Matx21f m(x0,x1)</code><br><code>cv::Matx23f m(x0,x1,x2,x3,x4,x5) //2行3列，从左到右，从上到下</code></td> 
  </tr> 
  <tr> 
   <td align="left">含相同元素的矩阵</td> 
   <td align="left"><code>m33f = cv::Matx33f::all(x)</code></td> 
  </tr> 
  <tr> 
   <td align="left">全零矩阵</td> 
   <td align="left"><code>m23d = cv::Matx23d::zeros()</code></td> 
  </tr> 
  <tr> 
   <td align="left">全一矩阵</td> 
   <td align="left"><code>m16f = cv::Matx16f::ones()</code></td> 
  </tr> 
  <tr> 
   <td align="left">单位矩阵</td> 
   <td align="left"><code>m33f = cv::Matx33f::eye()</code></td> 
  </tr> 
  <tr> 
   <td align="left">创建可容纳另一个矩阵对角线的矩阵</td> 
   <td align="left"><code>m31f = cv::Matx33f::diag()</code></td> 
  </tr> 
  <tr> 
   <td align="left">创建一个均匀分布的矩阵</td> 
   <td align="left"><code>m33f = cv::Matx33f::randu(min,max)</code></td> 
  </tr> 
  <tr> 
   <td align="left">创建一个正态分布的矩阵</td> 
   <td align="left"><code>m33f = cv::Matx33f::nrandn(mean,variance)</code></td> 
  </tr> 
  <tr> 
   <td align="left">成员访问</td> 
   <td align="left"><code>m(i,j) m(i)</code></td> 
  </tr> 
  <tr> 
   <td align="left">矩阵代数运算</td> 
   <td align="left"><code>m1=m0 m0*m1 m0+m1 m0-m1</code></td> 
  </tr> 
  <tr> 
   <td align="left">singleton代数</td> 
   <td align="left"><code>m*a a*m m/a</code></td> 
  </tr> 
  <tr> 
   <td align="left">比较</td> 
   <td align="left"><code>m1==m2 m1!=m2</code></td> 
  </tr> 
  <tr> 
   <td align="left">点积</td> 
   <td align="left"><code>m1.dot(m2)</code><br><code>m1.ddot(m2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">改变矩阵形状</td> 
   <td align="left"><code>m91f = m33f.reshape&lt;9,1&gt;()</code></td> 
  </tr> 
  <tr> 
   <td align="left">变换操作符</td> 
   <td align="left"><code>m44f = (cv::Matx44f) m44d</code></td> 
  </tr> 
  <tr> 
   <td align="left">提取(i,j)处2*2的子矩阵</td> 
   <td align="left"><code>m44f.get_minor&lt;2,2&gt;(i,j)</code></td> 
  </tr> 
  <tr> 
   <td align="left">提取第i行</td> 
   <td align="left"><code>m14f = m44f.row(i)</code></td> 
  </tr> 
  <tr> 
   <td align="left">提取第j列</td> 
   <td align="left"><code>m41f = m44f.col(j)</code></td> 
  </tr> 
  <tr> 
   <td align="left">提取矩阵对角线</td> 
   <td align="left"><code>m41f = m44f.diag()</code></td> 
  </tr> 
  <tr> 
   <td align="left">计算转置</td> 
   <td align="left"><code>n44f = m44f.t()</code></td> 
  </tr> 
  <tr> 
   <td align="left">逆矩阵</td> 
   <td align="left"><code>n44f = m44f.inv(method)</code></td> 
  </tr> 
  <tr> 
   <td align="left">解线性系统</td> 
   <td align="left"><code>m31f = m33f.solve(rhs31f,method)</code><br><code>m32f = m33f.solve&lt;2&gt;(rhs32f,method)</code></td> 
  </tr> 
  <tr> 
   <td align="left">每个元素的乘法</td> 
   <td align="left"><code>m1.mul(m2)</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Vec类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::Vec2s v2s</code><br><code>cv::Vec6f v6f</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::Vec3f u3f(v3f)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Vec2f v2f(x0,x1)</code><br><code>cv::Vec6d v6d(x0,x1,x2,x3,x4,x5)</code></td> 
  </tr> 
  <tr> 
   <td align="left">成员访问</td> 
   <td align="left"><code>v4f[i] v3w[j]</code></td> 
  </tr> 
  <tr> 
   <td align="left">向量叉乘</td> 
   <td align="left"><code>v3f.cross(u3f)</code></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <thead> 
  <tr> 
   <th align="left">cv::Scalar类支持的操作</th> 
   <th align="left">示例</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">默认构造函数</td> 
   <td align="left"><code>cv::Scalar s</code></td> 
  </tr> 
  <tr> 
   <td align="left">复制构造函数</td> 
   <td align="left"><code>cv::Scalar s2(s1)</code></td> 
  </tr> 
  <tr> 
   <td align="left">值构造函数</td> 
   <td align="left"><code>cv::Scalar s(x0)</code><br><code>cv::Scalar s(x,0,x1,x2,x3)</code></td> 
  </tr> 
  <tr> 
   <td align="left">元素相乘</td> 
   <td align="left"><code>s1.mul(s2)</code></td> 
  </tr> 
  <tr> 
   <td align="left">四元数共轭</td> 
   <td align="left"><code>s.conj()</code></td> 
  </tr> 
  <tr> 
   <td align="left">四元数真值测试</td> 
   <td align="left"><code>s.isReal()</code></td> 
  </tr> 
 </tbody> 
</table>

# 3、辅助对象 #

<table> 
 <thead> 
  <tr> 
   <th align="left">辅助对象</th> 
   <th align="left">作用</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">cv::TermCriteria</td> 
   <td align="left"><code>cv::TermCriteria(int type, int maxCount, double epsilon)</code><br>终止条件以确定何时退出</td> 
  </tr> 
  <tr> 
   <td align="left">cv::Range</td> 
   <td align="left"><code>cv::Range(int start, int end)</code><br>确定一个连续的整数序列</td> 
  </tr> 
  <tr> 
   <td align="left">cv::Ptr</td> 
   <td align="left"><code>cv::Ptr&lt;Matx33f&gt; p(new cv::Matx33f)</code><br><code>cv::Ptr&lt;Matx33f&gt; p = makePtr&lt;cv::Matx33f&gt;()</code><br>智能指针</td> 
  </tr> 
  <tr> 
   <td align="left">cv::Exception</td> 
   <td align="left"><code>CV_Error(errorcode, description)</code><br><code>CV_Error_(errorcode, printf_mt_str, [printf-args])</code><br><code>CV_Assert(condition)</code><br><code>CV_DbgAssert(condition)</code><br>抛出异常，处理错误</td> 
  </tr> 
  <tr> 
   <td align="left">cv::DataType&lt;&gt;</td> 
   <td align="left">传输特定数据类型</td> 
  </tr> 
  <tr> 
   <td align="left">cv::InputArray<br>cv::OutputArray<br>cv::InputOutputArray<br>cv::noArray</td> 
   <td align="left">常用于形参，可接受任意数组类型（如cv::Vec，cv::Mat等）作为初始值</td> 
  </tr> 
 </tbody> 
</table>

# 4、工具函数 #

<table> 
 <thead> 
  <tr> 
   <th align="left">工具函数和系统函数</th> 
   <th align="left">描述</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">cvCeil(x)</td> 
   <td align="left">对浮点数向上取整</td> 
  </tr> 
  <tr> 
   <td align="left">cvFloor(x)</td> 
   <td align="left">对浮点数向下取整</td> 
  </tr> 
  <tr> 
   <td align="left">cvRound(x)</td> 
   <td align="left">计算与浮点数最接近的整数</td> 
  </tr> 
  <tr> 
   <td align="left">cvIsInf(x)</td> 
   <td align="left">判断浮点数是否是正负无穷</td> 
  </tr> 
  <tr> 
   <td align="left">cvIsNan(x)</td> 
   <td align="left">判断浮点数是否不是一个数</td> 
  </tr> 
  <tr> 
   <td align="left">cv::fastAtan2(y,x)</td> 
   <td align="left">计算向量的二维角度（0~360）</td> 
  </tr> 
  <tr> 
   <td align="left">cv::cubeRoot(x)</td> 
   <td align="left">计算立方根</td> 
  </tr> 
  <tr> 
   <td align="left">cv::format(fmt, …)</td> 
   <td align="left">以sprintf类似，创建一个STL字符串</td> 
  </tr> 
  <tr> 
   <td align="left">cv::getOptimalDFTSize(n)</td> 
   <td align="left">计算传递给cv::dft()的数组的最适宜大小</td> 
  </tr> 
  <tr> 
   <td align="left">cv::alignPtr(ptr,n)</td> 
   <td align="left">对齐指针到给定字节数</td> 
  </tr> 
  <tr> 
   <td align="left">cv::alignSize(sz,n)</td> 
   <td align="left">将缓冲区大小与给定的字节数对齐</td> 
  </tr> 
  <tr> 
   <td align="left">cv::allocate(sz)</td> 
   <td align="left">与new类似，分配一个C风格的数组对象</td> 
  </tr> 
  <tr> 
   <td align="left">cv::deallocate(ptr, sz)</td> 
   <td align="left">与delete类似，释放一个C风格的数组对象</td> 
  </tr> 
  <tr> 
   <td align="left">cv::fastMalloc(size)</td> 
   <td align="left">与malloc类似，分配一个对齐的内存缓冲区</td> 
  </tr> 
  <tr> 
   <td align="left">cv::fastFree(ptr)</td> 
   <td align="left">与free类似，释放一个cv::fastMalloc()分配的内存</td> 
  </tr> 
  <tr> 
   <td align="left">cv::getCPUTickCount()</td> 
   <td align="left">获取CPU的tick数</td> 
  </tr> 
  <tr> 
   <td align="left">cv::getTickCount()</td> 
   <td align="left">获取系统的tick数</td> 
  </tr> 
  <tr> 
   <td align="left">cv::getTickFrequency()</td> 
   <td align="left">每秒的tick数</td> 
  </tr> 
  <tr> 
   <td align="left">cv::setNumThreads(nthreads)</td> 
   <td align="left">设置使用的线程数</td> 
  </tr> 
  <tr> 
   <td align="left">cv::getNumThreads()</td> 
   <td align="left">获取当前使用的线程数</td> 
  </tr> 
  <tr> 
   <td align="left">cv::getThreadNum()</td> 
   <td align="left">获取当前执行的线程的索引</td> 
  </tr> 
  <tr> 
   <td align="left">cv::setUseOptimized(on_off)</td> 
   <td align="left">开启或关闭代码优化功能</td> 
  </tr> 
  <tr> 
   <td align="left">cv::useOptimized()</td> 
   <td align="left">判断是否开启代码优化</td> 
  </tr> 
  <tr> 
   <td align="left">cv::CV_Assert(expt)<br>cv::CV_DbgAssert(expt)</td> 
   <td align="left">判断expt，若为false则抛出异常</td> 
  </tr> 
  <tr> 
   <td align="left">cv::CV_Error(ecode, estring)<br>cv::CV_Error_(ecode, fmt, …)</td> 
   <td align="left">构造cv::Exception并抛出一个异常</td> 
  </tr> 
  <tr> 
   <td align="left">cv::error(ex)</td> 
   <td align="left">提示错误并抛出异常</td> 
  </tr> 
 </tbody> 
</table>

# 5、模板结构 #

<table> 
 <thead> 
  <tr> 
   <th align="left">通用的固定长度模板</th> 
   <th align="left">描述</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="left">cv::Point_</td> 
   <td align="left">包含两个对象的点，对象类型为T</td> 
  </tr> 
  <tr> 
   <td align="left">cv::Rect_</td> 
   <td align="left">位置和宽高的类型均为T</td> 
  </tr> 
  <tr> 
   <td align="left">cv::Vec&lt;Type T, int H&gt;</td> 
   <td align="left">一个集合，元素的类型为T</td> 
  </tr> 
  <tr> 
   <td align="left">cv::Matx&lt;Type T, int H, int W&gt;</td> 
   <td align="left">一个H*W的矩阵，元素的类型为T</td> 
  </tr> 
  <tr> 
   <td align="left">cv::Scalar_</td> 
   <td align="left">一个包含四个对象的集合（和cv::Vec&lt;T,4&gt;类似），对象类型为T</td> 
  </tr> 
 </tbody> 
</table>