Since version 2.2, the OpenCV library is divided into several modules. These modules are built in library fles located in the lib directory. They are:
??1 The opencv_core module that contains the core functionalities of the library, in particular, the basic data structures and arithmetic functions.
??2 The opencv_imgproc module that contains the main image processing functions.
??3 The opencv_highgui module that contains the image and video reading and writing functions, along with other user interface functions.
??4 The opencv_features2d module that contains the feature point detectors and descriptors and the feature point matching framework.
??5 The opencv_calib3d module that contains the camera calibration, two-view geometry estimation, and stereo functions.
? 6 The opencv_video module that contains the motion estimation, feature tracking, and foreground extraction functions and classes.
??7 The opencv_objdetect module containing the object detection functions such as the face and people detectors.
The library also includes other utility modules containing machine learning functions (opencv_ml), computational geometry algorithms (opencv_flann), contributed code (opencv_contrib), obsolete code (opencv_legacy), and GPU accelerated code (opencv_gpu).
All of these modules have a header fle associated with them (located in include directory).
Typical OpenCV C++ code will therefore start by including the required modules. For example
(and this is the suggested declaration style):
#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui/highgui.hpp>
If you see OpenCV code starting with:
?#include "cv.h"
it is because it uses the old style, before the library was restructured into modules.

翻譯：

???opencv自從2.2版本起，將庫(kù)分成很多模塊，這些模塊編譯成庫(kù)，放在opencv的lib文件夾下。他們分別是：

1. opencv_core 模塊 它包含庫(kù)的核心函數(shù)，實(shí)際上它包含基本的數(shù)據(jù)結(jié)構(gòu)和算術(shù)函數(shù)

2. opencv_imgproc 模塊 它包含主要的圖像處理函數(shù)

3. The opencv_highgui 模塊，它包含圖像和視頻的讀寫(xiě)函數(shù)以及用戶(hù)交互函數(shù)

4. opencv_features2d 模塊，它包含特征點(diǎn)的檢測(cè)、描述以及匹配的框架

5. opencv_calib3d 模塊，它包含攝像頭的校準(zhǔn)，雙目幾何估計(jì)和立體函數(shù)

6. opencv_video 模塊，它包含運(yùn)動(dòng)目標(biāo)估計(jì)，特征跟蹤和前景提取的函數(shù)和類(lèi)

7. opencv_objdetect 模塊，它包含目標(biāo)檢測(cè)函數(shù)如人臉檢測(cè)，和行人檢測(cè)

opencv庫(kù)還包含其他單元模塊如機(jī)器學(xué)習(xí)模塊?(opencv_ml), 計(jì)算幾何算法模塊(opencv_flann), 已貢獻(xiàn)代碼模塊(opencv_contrib), 過(guò)時(shí)的代碼模塊opencv_legacy以及圖形加速模塊(opencv_gpu).
所有的模塊都有一個(gè)與之關(guān)聯(lián)的頭文件（在include路徑下）

典型的OPENCV c++代碼通常以包含這些必須的模塊開(kāi)始，如：

#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui/highgui.hpp>

OPENCV2.2源文件的結(jié)構(gòu)