1、前期準備工作

a. 安裝交叉編譯鏈
  我使用的是arm-linux-gcc 4.3.2，解壓到目錄/usr/local/arm/4.3.2，然後在環境變數PATH中增加/usr/local/arm/4.3.2/bin

b. 安裝CMake
  Opencv 2.0之後的版本，必須使用CMake建立Makefile。我使用的CMake版本是2.8.2，解壓到目錄/usr/local/cmake-2.8.2-Linux-i386，然後在環境變數PATH中增加/usr/local/cmake-2.8.2-Linux-i386/bin

2、編譯Opencv

1、解壓Opencv 2.4.9

2、建立build目錄，作為CMake編譯arm版本的工作目錄

3、在X環境下，執行cmake-gui（如果沒裝的話，按照提示安裝一個）
   選擇原始碼目錄
   選擇Build目錄：

點選Configure，保持generator為Unix Makefiles，選擇Specify options for cross-compiling，點選Next
Operating System填寫arm-inux

點選NEXT再跳出的介面中做如下設定

Operating System 選擇目標系統arm-linux

Compilers中選擇交叉編譯器的gcc和g++

Target Root選擇交叉編譯器的路徑

程式庫的Target Root填寫/usr/local/arm/，然後點選Finish

點選Finish按鈕，開始生成配置檔案，但是這個時候會報錯

System is unknown to cmake, create:

Platform/arm-linux to use this system, please send your config file to [email protected] so it can be added to cmake

但是這個時候還有其他錯誤

CMake Error at cmake/FindCUDA.cmake:763 (if):

if given arguments:

"CUDA_VERSION" "VERSION_GREATER" "5.0" "AND" "CMAKE_CROSSCOMPILING" "AND" "MATCHES" "arm"

Unknown arguments specified

Call Stack (most recent call first):

cmake/OpenCVDetectCUDA.cmake:26 (find_package)

cmake/OpenCVFindLibsPerf.cmake:24 (include)

CMakeLists.txt:468 (include)

修改預設配置，預設安裝目錄為/usr/local，由於我之前有裝x86版的opencv,所以對於交叉編譯的庫來說並不合適，所以我把CMAKE_INSTALL_PREFIX變數改為/usr/local/arm/

4、 點選Generate生成Makefile

(1)如果你現在make，是肯定會出錯的！（不修改，可能白等了至少15分鐘，前車之鑑）

../../lib/libopencv_core.so: undefined reference to `pthread_spin_init'

../../lib/libopencv_core.so: undefined reference to `pthread_spin_unlock'
../../lib/libopencv_core.so: undefined reference to `pthread_spin_lock'
../../lib/libopencv_core.so: undefined reference to `pthread_spin_destroy'
../../lib/libopencv_core.so: undefined reference to `pthread_once'
../../lib/libopencv_core.so: undefined reference to `clock_gettime'
../../lib/libopencv_core.so: undefined reference to `pthread_spin_trylock'

原因是找不到pthread連結庫，開啟資料夾下的CmakeCache.txt進行修改

//Flags used by the linker.(大概在194行附近)
CMAKE_EXE_LINKER_FLAGS:STRING=-lpthread -lrt  

(2)  opencv編譯OPENEXR時要用到libImath.so，

在配置介面要把build_opencvxr和with_opencvxr去掉，否則會出現這個問題。

/usr/lib/libImath.so: could not read symbols: File in wrong format

collect2: ld returned 1 exit status

make[2]: *** [lib/libopencv_highgui.so] 錯誤 1

make[1]: *** [modules/highgui/CMakeFiles/opencv_highgui.dir/all] 錯誤 2 make: *** [all] 錯誤 2

還要去掉build_opencv_ocl和with_opencl,否則會出下面的錯誤

../../lib/libopencv_ocl.so:undefined reference to 'dlopen'

還要去掉tiff庫的編譯

5、make

6、sudo make install

3、測試opencv庫是否安裝正確

<span style="font-family:SimSun;font-size:14px;">#include "cv.h"
#include"highgui.h"
const char*picture = "lena.jpg";
int main(int argc,char** argv)
{
	IplImage *pImage=cvLoadImage(picture,1);
	cvNamedWindow("Test",CV_WINDOW_AUTOSIZE);
	cvShowImage("Test",pImage);
	cvWaitKey(0);
	cvReleaseImage(&pImage);
	cvDestroyWindow("Test");
}
</span>

<span style="font-family:SimSun;font-size:14px;">all:test
CFLAGS=-Wall
OPENCV_INCLUDE=-I /usr/local/arm/include/opencv
CC = arm-linux-g++
OPENCV_LINK =-L/usr/local/arm/lib -lcv -lcxcore -lhighgui -lpthread -lrt
%:%.cpp
#$(CC) `pkg-config opencv --libs` $(OPENCV_INCLUDE) $< -o [email protected] $(OPENCV_LINK)
	$(CC) $(OPENCV_INCLUDE) $< -o [email protected] $(OPENCV_LINK)
.PHONY:clean
clean:
	rm -f test
</span>

4、移植到mini2440開發板上

首先複製主機/usr/local/arm/lib//下面的全部.so檔案到嵌入式根檔案系統的/lib/目錄下，再複製我們編譯的test到嵌入式系統/opt/myworks/目錄下（並確保檔案test屬性為可執行），如果test可正常執行沒有報告缺少庫檔案，說明我們編譯的arm-linux版OpenCV庫已經可以正常使用。