1、环境配置: Android NDK Android studio 2、下载头文件: 大家可以通过这个链接下载头文件:
http://download.csdn.net/detail/wjskeepmaking/9811058
【Android OpenCL测试程序,使用dlopen动态加载libOpenCL.so库】
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3、声明native函数并生成头文件:
public class OpenclTest {public String testOpencl(){
return testopencl();
}
public String getplatformName(){
return getPlatformName();
}
public String getdeviceName(){
return getDeviceName();
}public native Stringtestopencl();
public native String getPlatformName();
public native String getDeviceName();
}
进入package的同级目录,利用javah命令生成头文件:
![Android OpenCL测试程序,使用dlopen动态加载libOpenCL.so库](https://img.it610.com/image/info8/41a92180fbb54888a668e56f22a68cac.jpg)
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4、编写ocl.cpp文件:
//
// Created by wujs on 2017/4/11.
//
#include "CL/cl.h"
#include
#include
#include
#include
#include "topencl.h"
#include"com_pax_imagesobelfilter_OpenclTest.h"
#include
#define LOG_TAG "test"
#define LOGD(...) ((void)__android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__))
#define LEN(arr) sizeof(arr) / sizeof(arr[0])
#define N 1024
#define NUM_THREAD 128cl_uint num_device;
cl_uint num_platform;
cl_platform_id *platform;
cl_device_id *devices;
cl_int err;
cl_context context;
cl_command_queue cmdQueue;
cl_mem buffer,sum_buffer;
cl_program program ;
cl_kernel kernel;
const char* src[] = {
"__kernel void redution(\n"
"__global int *data,\n"
"__global int *output,\n"
"__local int *data_local\n"
")\n"
" {\n"
"int gid=get_group_id(0);
\n"
"int tid=get_global_id(0);
\n"
"int size=get_local_size(0);
\n"
"int id=get_local_id(0);
\n"
"data_local[id]=data[tid];
\n"
"barrier(CLK_LOCAL_MEM_FENCE);
\n"
"for(int i=size/2;
i>0;
i>>=1){\n"
"if(idNewStringUTF(result);
}
JNIEXPORT jstring JNICALL Java_com_pax_imagesobelfilter_OpenclTest_getPlatformName(JNIEnv *env , jobject thisobject)
{
char buffer[1024];
LOGD("getPlatformName start");
clGetPlatformInfo(platform[0],CL_PLATFORM_NAME,sizeof(buffer),buffer,NULL);
return env->NewStringUTF(buffer);
}
JNIEXPORT jstring JNICALL Java_com_pax_imagesobelfilter_OpenclTest_getDeviceName(JNIEnv *env , jobject thisobject)
{char buffer[1024];
LOGD("getDeviceName start");
clGetDeviceInfo(devices[0],CL_DEVICE_NAME,sizeof(buffer),buffer,NULL);
return env->NewStringUTF(buffer);
}void Init_OpenCL()
{
LOGD("start init OpenCL");
size_t nameLen1;
char platformName[1024];
err = clGetPlatformIDs(0, 0, &num_platform);
LOGD("err=clGetPlatformIDs");
platform=(cl_platform_id*)malloc(sizeof(cl_platform_id)*num_platform);
err = clGetPlatformIDs(num_platform, platform, NULL);
err=clGetDeviceIDs(platform[0],CL_DEVICE_TYPE_GPU,0,NULL,&num_device);
devices=(cl_device_id*)malloc(sizeof(cl_device_id)*num_device);
err=clGetDeviceIDs(platform[0],CL_DEVICE_TYPE_GPU,num_device,devices,NULL);
}void Context_cmd()
{
context=clCreateContext(NULL,num_device,devices,NULL,NULL,&err);
cmdQueue=clCreateCommandQueue(context,devices[0],0,&err);
}void Create_Buffer(int *data)
{buffer=clCreateBuffer(context,CL_MEM_READ_ONLY|CL_MEM_COPY_HOST_PTR,sizeof(int)*N,data,&err);
sum_buffer=clCreateBuffer(context,CL_MEM_WRITE_ONLY,sizeof(int)*num_block,0,&err);
}void Create_program()
{
program=clCreateProgramWithSource(context, LEN(src), src, NULL, NULL);
err=clBuildProgram(program,num_device,devices,NULL,NULL,NULL);
kernel = clCreateKernel(program, "redution", NULL);
}void Set_arg()
{
err=clSetKernelArg(kernel,0,sizeof(cl_mem),&buffer);
err=clSetKernelArg(kernel,1,sizeof(cl_mem),&sum_buffer);
err=clSetKernelArg(kernel,2,sizeof(int)*NUM_THREAD,NULL);
}void Execution()
{
const size_t globalWorkSize[1]={N};
const size_t localWorkSize[1]={NUM_THREAD};
err=clEnqueueNDRangeKernel(cmdQueue,kernel,1,NULL,globalWorkSize,localWorkSize,0,NULL,NULL);
clFinish(cmdQueue);
}void CopyOutResult(int*out)
{
err=clEnqueueReadBuffer(cmdQueue,sum_buffer,CL_TRUE,0,sizeof(int)*num_block,out,0,NULL,NULL);
}
5、创建topencl.h文件和topencl.c文件; 利用dlopen,实现动态加载libOpenCL.so库,由于代码太多,这里就不全部贴出来了,后面会有链接,大家可以去下载,根据自己的实际情况修改,需要修改的地方不会很多。 Note:下面代码是从系统中去加载动态库,这里有个问题,如果大家使用的机器是Android N以下,加载不会出错,但是,如果是Android N或以上的,加载会出现问题,因为从Android N开始,限制了程序对系统私有库(除了Android NDK中提供的那些库)的加载了。针对这种情况,现在的解决方法就是:把需要加载和依赖的库全部导入APP中,直接从APP中去加载,大家可以参阅这篇文章:解决Android N加载系统私有库的错误。 下面是topencl.c的库加载代码:
#define LIB_OPENCL "/system/vendor/lib/libOpenCL.so"
#define LIB_GLES_MALI "/system/vendor/lib/egl/libGLES_adreno.so"
#define LIB_LLVM"/system/lib/libllvm-a3xx.so"static void *getCLHandle(){LOGD("get_handle");
void *res = NULL;
char* so_name="Unknown Shared library for OpenCL";
res = dlopen(LIB_OPENCL,RTLD_LAZY);
if(res != NULL){
so_name = LIB_OPENCL;
}else{
res = dlopen(LIB_GLES_MALI,RTLD_LAZY);
}
if(res != NULL){
so_name = LIB_GLES_MALI;
}else{
res = dlopen(LIB_LLVM,RTLD_LAZY);
}
/*if(res==NULL){
res = dlopen("/home/rahul/stream/sdk2.7/lib/x86_64/libOpenCL.so",RTLD_LAZY);
}*/
if(res != NULL) {
so_name=LIB_LLVM;
} else {
LOGD("Could not open library :(\n");
}
LOGD("Loaded library name:%s\n",so_name);
return res;
}
6、编写Android.mk文件和Application.mk文件: android.mk文件:
要根据自己的Opencv4Android的路径去修改OPENCV_ANDROID_SDK
LOCAL_PATH := $(call my-dir)include $(CLEAR_VARS)
OPENCV_ANDROID_SDK := F:\Android\opencv-3.2.0-android-sdk\OpenCV-android-sdk
ifdef OPENCV_ANDROID_SDK
ifneq ("","$(wildcard $(OPENCV_ANDROID_SDK)/OpenCV.mk)")
include ${OPENCV_ANDROID_SDK}/OpenCV.mk
else
include ${OPENCV_ANDROID_SDK}/sdk/native/jni/OpenCV.mk
endif
else
include ../../sdk/native/jni/OpenCV.mk
endifLOCAL_MODULE:= ocl
LOCAL_CPPFLAGS += -I$(LOCAL_PATH)
LOCAL_SRC_FILES := ocl.cpp topencl.c
LOCAL_LDLIBS += -llog -ldl
include $(BUILD_SHARED_LIBRARY)
Application.mk文件:
APP_CPPFLAGS := -frtti -fexceptions
#APP_STL := stlport_static
APP_STL := gnustl_static
APP_ABI := armeabi-v7a arm64-v8a
APP_PLATFORM := android-8
7、编译: 进入 jni 的同级目录,利用ndk-build进行编译:
![Android OpenCL测试程序,使用dlopen动态加载libOpenCL.so库](https://img.it610.com/image/info8/728156a11fa54c1fa4c16d53f3ef6de9.png)
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、
8、程序运行结果:
![Android OpenCL测试程序,使用dlopen动态加载libOpenCL.so库](https://img.it610.com/image/info8/ef60730edf9d4a5c904a8211e05ddf81.jpg)
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以上例程是参考这篇博文写的:http://blog.csdn.net/wcj0626/article/details/26272019#comments。但这个链接中使用静态库进行编译的。所以,我在这里写一个通过 动态加载手机中的OpenCL库的文章,供大家参考使用。我的另一篇文章,使用opencv T-API来获取GPU信息: Opencv4Android的OpenCL的测试,使用Opencv的ocl封装库
代码链接: CSDN OpenCV manager因为Opencv4Android sdk 太大了,所以,我从代码中剔除之后再上传的,如果大家下载学习,要把Opencv4Android SDK 导入和安装OpenCV manager.apk(上面提供了连链接下载,除了X86和X86_64)之后才能正确运行。 如果大家有什么疑问,也请在评论中提出,能回答尽量回答,大家互相学习。