Opencv3.1.0移植/人臉識(shí)別

opencv3.1.0移植到7688

修改/home/xl/OpenCV/opencv-3.1.0/platforms/linux目錄下的

arm-gnueabi.toolchain.cmake這個(gè)文件，為了區(qū)分其它的配置文件我改名為arm-gnueabi_7688.toolchain.cmake，

修改后如下：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image002.jpg

為方便管理創(chuàng)建opencv_7688目錄,在它下面再創(chuàng)建兩個(gè)目錄

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image004.jpg

進(jìn)入7688_build_dir 目錄執(zhí)行下面這條命令

$ cmake -D CMAKE_BUILD_TYPE=Release-D CMAKE_INSTALL_PREFIX=../7688_install_dir/ -D SOFTFP=ON -D ENABLE_NEON=ON -DCMAKE_TOOLCHAIN_FILE=../../arm-gnueabi_7688.toolchain.cmake ../../../../

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image006.jpg

注意路徑要對(duì)應(yīng)，最后面是源碼目錄

正常結(jié)束如下：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image008.jpg

之后在當(dāng)前目錄下多了許多文件如下：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image010.jpg

前面只是配置還不真正編譯，執(zhí)行make開(kāi)始編譯

移植opencv3.1.0到gk8602

修改/home/xl/OpenCV/opencv-3.1.0/platforms/linux目錄下的

arm-gnueabi.toolchain.cmake這個(gè)文件，修改如下

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image012.jpg

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image014.jpg

然后在當(dāng)前目錄下創(chuàng)建兩個(gè)文件夾，gk8602_build_dir，gk8602_install_dir，

進(jìn)入gk8602_build_dir目錄執(zhí)行如下一條命令

cmake -DCMAKE_BUILD_TYPE=Release -D CMAKE_INSTALL_PREFIX=../ gk8602_install_dir / -DSOFTFP=ON -D ENABLE_NEON=ON -DCMAKE_TOOLCHAIN_FILE=../arm-gnueabi.toolchain.cmake ../../../  

之后會(huì)在當(dāng)前目錄下生成許多文件及目錄，如下圖：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image016.jpg

再執(zhí)行make命令進(jìn)行編譯，make install 安裝（會(huì)自動(dòng)安裝到gk8602_install_dir目錄，這里的內(nèi)容是要放到開(kāi)發(fā)板上去的）

為方便管理，在linux目錄下創(chuàng)建一個(gè)gk_test目錄，如下

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image018.jpg

進(jìn)入gk_test目錄編寫(xiě)cpp文件

$vim  LoadImage.cpp

#include <iostream>

#include <string>

#include <opencv2/opencv.hpp>

using namespace std;

using namespace cv;

int main(int argc,char* argv[]){

    string path="/home/zzz/facedata/lena.jpg";

     Mat image = imread(path, 1 );

     if(image.isContinuous()){

         cout<<"read picture successfully!"<<endl;

     }else{

         cout<<"fail to read picture!"<<endl;

     }

     return 0;

}

再編寫(xiě)CMakeLists.txt文件如下：

# this is required

set(CMAKE_SYSTEM_NAME Linux)

#注意文件對(duì)應(yīng)的路徑別弄錯(cuò)了

set(CMAKE_FIND_ROOT_PATH/opt/goke/ct_glibc/4.6.1/usr/ /opt/goke/ct_glibc/4.6.1/usr)

set(ARM_LINUX_SYSROOT/opt/goke/ct_glibc/4.6.1/usr/ CACHE PATH "ARM cross compile systemroot")

# search for programs in the buildhost directories (not necessary)

SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAMNEVER)

# for libraries and headers inthe target directories

SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARYONLY)

SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDEONLY)

set(TOOLCHAIN_DIR"/opt/goke/ct_glibc/4.6.1/usr/")

set(CMAKE_C_COMPILER"/opt/goke/ct_glibc/4.6.1/usr/bin/arm-goke-linux-gnueabi-gcc")

set(CMAKE_CXX_COMPILER"/opt/goke/ct_glibc/4.6.1/usr/bin/arm-goke-linux-gnueabi-g++")

set(CMAKE_VERBOSE_MAKEFILE ON)

cmake_minimum_required(VERSION2.8)

project( LoadImage )

set(OpenCV_DIR/home/xl/OpenCV/opencv-3.1.0/platforms/linux/gk8602_build_dir/)

include_directories(/home/xl/OpenCV/opencv-3.1.0/platforms/linux/gk8602_install_dir/include)

#set(OpenCV_DIR /home/zzz/software/opencv-2.4.9/release)

#include_directories(/home/zzz/software/opencv-2.4.9/build/include)

find_package( OpenCV REQUIRED )

add_executable( LoadImageLoadImage.cpp )

target_link_libraries(LoadImage ${OpenCV_LIBS} )

再執(zhí)行cmake. 如下：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image020.jpg

執(zhí)行后如下：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image022.jpg

編譯時(shí)出錯(cuò)如下：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image024.jpg

于是修改CMakeCache.txt加下下面一個(gè)標(biāo)志

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image026.jpg

加了上面的內(nèi)容后再make如下提示：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image028.jpg

修改CMakeLists.txt如下，直接指定庫(kù)的路徑

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image030.jpg

再編譯出錯(cuò)：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image032.jpg

用ar –t命令查看下庫(kù)里面包含的文件，再用ar –x 把庫(kù)里的文件取出來(lái)，看下是什么格式，如下：

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image034.jpg

發(fā)現(xiàn)庫(kù)的是x86_64的，而我們要用在開(kāi)發(fā)板上應(yīng)該是這種格式才行

file:///C:/Users/Administrator/AppData/Local/Temp/msohtmlclip1/01/clip_image036.jpg

移植opencv3.1.0到hi3516a

參考文章：

一、交叉編譯opencv3.1.0

1、修改cmake文件
在源碼的platforms下已經(jīng)有對(duì)各平臺(tái)的交叉編譯支持，我們只需要做一些簡(jiǎn)單的修改。

[zzz@localhostplatforms]$ pwd

/home/zzz/software/opencv-3.1.0/platforms

[zzz@localhostplatforms]$ ll

total 28

drwxr-xr-x. 4 zzz zzz 4096 Dec 18 23:02 android

drwxr-xr-x. 3 zzz zzz 4096 Dec 18 23:02 ios

drwxr-xr-x. 4 zzz zzz 4096 Jan 22 17:24 linux

drwxr-xr-x. 2 zzz zzz 4096 Dec 18 23:02 osx

-rw-r--r--. 1 zzz zzz  323 Dec 18 23:02 readme.txt

drwxr-xr-x. 2 zzz zzz 4096 Dec 18 23:02 scripts

drwxr-xr-x. 2 zzz zzz 4096 Dec 18 23:02 winrt

我們的目標(biāo)是交叉編譯到arm上，那么就進(jìn)入到linux下：

[zzz@localhost linux]$ pwd

/home/zzz/software/opencv-3.1.0/platforms/linux

[zzz@localhost linux]$ ll

total 20

-rw-r--r--.  1 zzz zzz 4196 Jan22 16:35arm-gnueabi.toolchain.cmake

...

arm-gnueabi.toolchain.cmake指明了交叉編譯的一些路徑等設(shè)置，我們根據(jù)實(shí)際情況對(duì)其進(jìn)行適當(dāng)修改：

set(CMAKE_SYSTEM_NAMELinux)

set(CMAKE_SYSTEM_VERSION1)

set(CMAKE_SYSTEM_PROCESSORarm-hisiv300-linux-gnueabi)

set(GCC_COMPILER_VERSION"4.6" CACHE STRING "GCCCompiler version")

set(FLOAT_ABI_SUFFIX"")

if (NOT SOFTFP)

    set(FLOAT_ABI_SUFFIX"hf")

endif()

#CROSS COMPILESETTING

set(TOOLCHAIN_DIR"/opt/hisi-linux/x86-arm/arm-hisiv300-linux/")

set(CMAKE_C_COMPILER"/opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-gcc")

set(CMAKE_CXX_COMPILER"/opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-g++")

set(CMAKE_FIND_ROOT_PATH/opt/hisi-linux/ /opt/hisi-linux/x86-arm/arm-hisiv300-linux/)

set(ARM_LINUX_SYSROOT/opt/hisi-linux/x86-arm/arm-hisiv300-linux/ CACHE PATH "ARM cross compile system root")

MESSAGE(STATUS "Thisis cross compile dir --->"$(CMAKE_C_COMPILER))

#find_program(CMAKE_C_COMPILER NAMESarm-linux-gnueabi${FLOAT_ABI_SUFFIX}-gcc-${GCC_COMPILER_VERSION})

#find_program(CMAKE_CXX_COMPILER NAMESarm-linux-gnueabi${FLOAT_ABI_SUFFIX}-g++-${GCC_COMPILER_VERSION})

#set(ARM_LINUX_SYSROOT /usr/arm-linux-gnueabi${FLOAT_ABI_SUFFIX}CACHE PATH "ARM cross compilation systemroot")

#set(CMAKE_CXX_FLAGS          ""                    CACHESTRING "c++ flags")

#set(CMAKE_C_FLAGS            ""                    CACHESTRING "c flags")

#set(CMAKE_SHARED_LINKER_FLAGS ""                    CACHE STRING "shared linker flags")

#set(CMAKE_MODULE_LINKER_FLAGS ""                    CACHE STRING "module linker flags")

#set(CMAKE_EXE_LINKER_FLAGS   "-Wl,-z,nocopyreloc"  CACHE STRING "executable linker flags")

set(CMAKE_CXX_FLAGS"${CMAKE_CXX_FLAGS} -mthumb-fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi")

set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}-mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi")

set(CMAKE_SHARED_LINKER_FLAGS"-Wl,--fix-cortex-a8-Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now${CMAKE_SHARED_LINKER_FLAGS}")

set(CMAKE_MODULE_LINKER_FLAGS"-Wl,--fix-cortex-a8-Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now${CMAKE_MODULE_LINKER_FLAGS}")

set(CMAKE_EXE_LINKER_FLAGS    "-Wl,--fix-cortex-a8-Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now${CMAKE_EXE_LINKER_FLAGS}")

if(USE_NEON)

  message(WARNING "You use obsolete variable USE_NEON to enable NEONinstruction set. Use -DENABLE_NEON=ON instead." )

  set(ENABLE_NEONTRUE)

elseif(USE_VFPV3)

  message(WARNING "You use obsolete variable USE_VFPV3 to enable VFPV3instruction set. Use -DENABLE_VFPV3=ON instead." )

  set(ENABLE_VFPV3TRUE)

endif()

#set(CMAKE_FIND_ROOT_PATH ${CMAKE_FIND_ROOT_PATH}${ARM_LINUX_SYSROOT})

if(EXISTS${CUDA_TOOLKIT_ROOT_DIR})

    set(CMAKE_FIND_ROOT_PATH${CMAKE_FIND_ROOT_PATH} ${CUDA_TOOLKIT_ROOT_DIR})

endif()

set(CMAKE_SKIP_RPATH TRUE CACHE BOOL "Ifset, runtime paths are not added when using shared libraries." )

set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDEONLY)

set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARYONLY)

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAMONLY)

# macro to find programs on the host OS

macro( find_host_program )

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER )

set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY NEVER )

set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE NEVER )

if( CMAKE_HOST_WIN32 )

  SET( WIN32 1 )

  SET( UNIX )

elseif(CMAKE_HOST_APPLE )

  SET( APPLE 1 )

  SET( UNIX )

endif()

find_program( ${ARGN})

SET( WIN32 )

SET( APPLE )

SET( UNIX 1 )

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY )

set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY )

set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY )

endmacro()

# macro to find packages on the host OS

macro( find_host_package )

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER )

set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY NEVER )

set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE NEVER )

if( CMAKE_HOST_WIN32 )

  SET( WIN32 1 )

  SET( UNIX )

elseif(CMAKE_HOST_APPLE )

  SET( APPLE 1 )

  SET( UNIX )

endif()

find_package( ${ARGN})

SET( WIN32 )

SET( APPLE )

SET( UNIX 1 )

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY )

set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY )

set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY )

endmacro()

2、交叉編譯
設(shè)置好了以后，開(kāi)始進(jìn)行交叉編譯：
建立好執(zhí)行cmake的路徑:build_softfp，建立好編譯后的安裝路徑：install_dir

[zzz@localhost linux]$ ll

total 20

-rw-r--r--.  1 zzz zzz4196 Jan 22 16:35 arm-gnueabi.toolchain.cmake

drwxrwxr-x. 15 zzz zzz4096 Jan 22 16:38 build_softfp

drwxrwxr-x.  6 zzz zzz4096 Jan 22 15:51 install_dir

執(zhí)行：

[zzz@localhost build_softfp]$ pwd

/home/zzz/software/opencv-3.1.0/platforms/linux/build_softfp

[zzz@localhost build_softfp]$ cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../install_dir/ -D SOFTFP=ON -DENABLE_NEON=ON -DCMAKE_TOOLCHAIN_FILE=../arm-gnueabi.toolchain.cmake ../../../

等待10幾分鐘。

之后還要執(zhí)行make ,makeinstall,完成，再執(zhí)行下面的測(cè)試

二、編寫(xiě)測(cè)試程序

1、程序內(nèi)容
簡(jiǎn)單測(cè)試對(duì)圖片的加載：

#include <iostream>

#include <string>

#include <opencv2/opencv.hpp>

using namespace std;

using namespace cv;

int main(int argc,char*argv[]){

   string path="/home/zzz/facedata/lena.jpg";

    Mat image = imread( path, 1 );

    if(image.isContinuous()){

         cout<<"read picture successfully!"<<endl;

    }else{

         cout<<"fail to read picture!"<<endl;

    }

    return 0;

}

2、編譯
CMakeLists.txt:

# this is required

set(CMAKE_SYSTEM_NAME Linux)

set(CMAKE_FIND_ROOT_PATH /opt/hisi-linux/ /opt/hisi-linux/x86-arm/arm-hisiv300-linux/)

set(ARM_LINUX_SYSROOT/opt/hisi-linux/x86-arm/arm-hisiv300-linux/ CACHE PATH "ARM cross compile system root")

# search for programs in the build host directories (notnecessary)

SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)

# for libraries and headers in the target directories

SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)

SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

set(TOOLCHAIN_DIR "/opt/hisi-linux/x86-arm/arm-hisiv300-linux/")

set(CMAKE_C_COMPILER "/opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-gcc")

set(CMAKE_CXX_COMPILER "/opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-g++")

set(CMAKE_VERBOSE_MAKEFILE ON)

cmake_minimum_required(VERSION 2.8)

project( LoadImage )

set(OpenCV_DIR /home/zzz/software/opencv-3.1.0/platforms/linux/build_softfp/)

include_directories(/home/zzz/software/opencv-3.1.0/platforms/linux/install_dir/include)

#set(OpenCV_DIR /home/zzz/software/opencv-2.4.9/release)

#include_directories(/home/zzz/software/opencv-2.4.9/build/include)

find_package( OpenCV REQUIRED )

add_executable( LoadImage LoadImage.cpp )

target_link_libraries( LoadImage ${OpenCV_LIBS} )

可以把上半部分的內(nèi)容抽取出來(lái)，作為交叉編譯的指示文件：

# this is required

set(CMAKE_SYSTEM_NAMELinux)

set(CMAKE_FIND_ROOT_PATH/opt/hisi-linux/ /opt/hisi-linux/x86-arm/arm-hisiv300-linux/)

set(ARM_LINUX_SYSROOT/opt/hisi-linux/x86-arm/arm-hisiv300-linux/ CACHE PATH "ARM cross compile system root")

# search for programs in the build host directories (not necessary)

SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAMNEVER)

# for libraries and headers in the target directories

SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARYONLY)

SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDEONLY)

set(TOOLCHAIN_DIR"/opt/hisi-linux/x86-arm/arm-hisiv300-linux/")

set(CMAKE_C_COMPILER"/opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-gcc")

set(CMAKE_CXX_COMPILER"/opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-g++")

set(CMAKE_VERBOSE_MAKEFILEON)

執(zhí)行如下：

[zzz@localhost basictest]$ cmake .

-- The C compiler identification is GNU 4.8.3

-- The CXX compiler identification is GNU 4.8.3

-- Check for working C compiler: /opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-gcc

-- Check for working C compiler: /opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-gcc-- works

-- Detecting C compiler ABI info

-- Detecting C compiler ABI info - done

-- Check for working CXX compiler: /opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-g++

-- Check for working CXX compiler: /opt/hisi-linux/x86-arm/arm-hisiv300-linux/bin/arm-hisiv300-linux-uclibcgnueabi-g++-- works

-- Detecting CXX compiler ABI info

-- Detecting CXX compiler ABI info - done

-- Configuring done

-- Generating done

-- Build files have been written to:/home/zzz/workspace/arm-opencv3.1.0/src/basictest

[zzz@localhost basictest]$ make

Scanning dependencies of targetLoadImage

[100%] Building CXX objectCMakeFiles/LoadImage.dir/LoadImage.cpp.o

Linking CXX executable LoadImage

[100%] Built target LoadImage

[zzz@localhost basictest]$

三、在板上運(yùn)行
需要設(shè)置好LD_LIBRARY_PATH，使其也指向一開(kāi)始生成的opencv的庫(kù)文件路徑，或者直接將這些庫(kù)拷貝到LD_LIBRARY_PATH指定的當(dāng)前路徑中。

四、問(wèn)題
一開(kāi)始沒(méi)有設(shè)定好cmake的交叉編譯設(shè)置，導(dǎo)致在編譯測(cè)試程序的時(shí)候，使用的是系統(tǒng)的c++編譯器在編譯鏈接，結(jié)果提示無(wú)法讀取opencv的so的符號(hào)等。所以對(duì)cmake的設(shè)置要在實(shí)踐中慢慢掌握全面一些。

后記（2016-1-28）：
由于使用的板子有浮點(diǎn)運(yùn)算單元以及neon，但是上面的編譯腳本沒(méi)有使用相關(guān)的參數(shù)，包括編譯opencv的庫(kù)以及編譯自己的執(zhí)行程序時(shí)都沒(méi)有用上。因此，編譯出來(lái)的程序沒(méi)有用上硬件浮點(diǎn)單元的特性。需要進(jìn)行修改：
1、修改opencv的交叉編譯腳本
主要是設(shè)置:

27

28 set(CMAKE_CXX_FLAGS           "-mthumb -mcpu=cortex-a7 -mfloat-abi=softfp-mfpu=neon-vfpv4 -mno-unaligned-access -fno-aggressi    ve-loop-optimizations"    CACHE STRING "c++ flags")

29 set(CMAKE_C_FLAGS             "${CMAKE_CXX_FLAGS}"                    CACHE STRING "c flags")

30 set(CMAKE_SHARED_LINKER_FLAGS"${CMAKE_CXX_FLAGS}"                    CACHE STRING "shared linkerflags")

31 set(CMAKE_MODULE_LINKER_FLAGS"${CMAKE_CXX_FLAGS}"                    CACHE STRING "module linkerflags")

32 set(CMAKE_EXE_LINKER_FLAGS    "${CMAKE_CXX_FLAGS}-Wl,-z,nocopyreloc"  CACHE STRING "executable linker flags")

33

34 #set(CMAKE_CXX_FLAGS"${CMAKE_CXX_FLAGS} -mthumb -fdata-sections-Wa,--noexecstack -fsigned-char -Wno-psabi")

35 #set(CMAKE_C_FLAGS   "${CMAKE_C_FLAGS}-mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi")

36

37 #set(CMAKE_SHARED_LINKER_FLAGS"-Wl,--fix-cortex-a8-Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-    z,now ${CMAKE_SHARED_LINKER_FLAGS}")

38 #set(CMAKE_MODULE_LINKER_FLAGS"-Wl,--fix-cortex-a8-Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-    z,now ${CMAKE_MODULE_LINKER_FLAGS}")

39 #set(CMAKE_EXE_LINKER_FLAGS    "-Wl,--fix-cortex-a8-Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-    z,now ${CMAKE_EXE_LINKER_FLAGS}")

40

我這里只需要生成so，是否只需要設(shè)置CMAKE_SHARED_LINKER_FLAGS這個(gè)就可以了？

2、編譯出來(lái)的so的情況：

[zzz@localhost build_softfp]$ cmake-D CMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../install_dir/ -D SOFTFP=ON-DENABLE_NEON=ON -DCMAKE_TOOLCHAIN_FILE=../arm-gnueabi.toolchain.cmake ../../../

[zzz@localhost build_softfp]$ readelf-a lib/libopencv_imgproc.so.2.4.9

...

Attribute Section: aeabi

File Attributes

Tag_CPU_name: "Cortex-A7"

Tag_CPU_arch: v7

Tag_CPU_arch_profile: Application

Tag_ARM_ISA_use: Yes

Tag_THUMB_ISA_use: Thumb-2

Tag_FP_arch: VFPv4

Tag_Advanced_SIMD_arch: NEONv1 with Fused-MAC

Tag_ABI_PCS_wchar_t: 4

Tag_ABI_FP_denormal: Needed

Tag_ABI_FP_exceptions: Needed

Tag_ABI_FP_number_model: IEEE 754

Tag_ABI_align_needed: 8-byte

Tag_ABI_enum_size: int

Tag_ABI_HardFP_use: SP and DP

Tag_CPU_unaligned_access: v6

Tag_MPextension_use: Allowed

Tag_DIV_use: Allowed in v7-A with integer division extension

Tag_Virtualization_use: TrustZone andVirtualization Extensions

[zzz@localhost build_softfp]$

·         

我加了一個(gè)-DENABLE_NEON=ON，不加也可以。

3、修改執(zhí)行程序的腳本
在toolchainfile里增加：

set(CMAKE_CXX_FLAGS          "-mthumb -mcpu=cortex-a7-mfloat-abi=softfp -mfpu=neon-vfpv4 -mno-unaligned-access-fno-aggressive-loop-optimizations"    CACHE STRING "c++ flags")

set(CMAKE_C_FLAGS            "${CMAKE_CXX_FLAGS}"                    CACHE STRING "c flags")

set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_CXX_FLAGS}"                    CACHE STRING "shared linkerflags")

set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_CXX_FLAGS}"                    CACHE STRING "module linkerflags")

set(CMAKE_EXE_LINKER_FLAGS   "${CMAKE_CXX_FLAGS}-Wl,-z,nocopyreloc"  CACHE STRING "executable linker flags")

經(jīng)過(guò)測(cè)試，其實(shí)不設(shè)置CMAEK_CXX_FLAGS,CMAKE_C_FLAGS及其他，只設(shè)置CMAKE_EXE_LINKER_FLAGS，都能達(dá)到目標(biāo)。
產(chǎn)生的exe的情況：

Attribute Section: aeabi

File Attributes

Tag_CPU_name: "Cortex-A7"

Tag_CPU_arch: v7

Tag_CPU_arch_profile: Application

Tag_ARM_ISA_use: Yes

Tag_THUMB_ISA_use: Thumb-2

Tag_FP_arch: VFPv4

Tag_Advanced_SIMD_arch: NEONv1 with Fused-MAC

Tag_ABI_PCS_wchar_t: 4

Tag_ABI_FP_denormal: Needed

Tag_ABI_FP_exceptions: Needed

Tag_ABI_FP_number_model: IEEE 754

Tag_ABI_align_needed: 8-byte

Tag_ABI_enum_size: int

Tag_ABI_HardFP_use: SP and DP

Tag_CPU_unaligned_access: v6

Tag_MPextension_use: Allowed

Tag_DIV_use: Allowed in v7-A with integer division extension

Tag_Virtualization_use: TrustZone andVirtualization Extensions