OpenCV opencv2/core/core.hpp: 没有这个文件或目录。

Question

我正在创建一个小项目，以测试在Android Studio 1.4上使用opencv（2.4）的功能，但当我尝试执行应用程序时，我遇到了NDK编译器的一个问题。我认为cpp文件找不到opencv的路径，但我不知道为什么。

有没有想法如何解决这个问题？

错误：

/home/User/AndroidStudioProjects/OpenCV/app/src/main/jni/native_processing.h Error:(10, 33) opencv2/core/core.hpp: No such file or directory

JNI：

OpenCV/app/src/main/jni/native_processing.cpp OpenCV/app/src/main/jni/native_processing.h

#ifndef OPENCV_SAMPLE_NATIVE_PROCESSING_H
#define OPENCV_SAMPLE_NATIVE_PROCESSING_H

#include <jni.h>

#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/features2d/features2d.hpp>
#include <vector>

extern "C" {
JNIEXPORT void JNICALL      Java_com_projeto_opencv_MainActivity_FindFeatures(JNIEnv *, jobject,
                                                                                 jlong addrGray,
                                                                                 jlong addrRgba);
 }
 #endif

Android.mk

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)
OPENCV_CAMERA_MODULES:=on
OPENCV_INSTALL_MODULES:=on
OPENCV_LIB_TYPE:=STATIC


PENCV_CAMERA_MODULES:=on
OPENCV_INSTALL_MODULES:=on
OPENCV_LIB_TYPE:=SHARED
include /home/User/AndroidStudioProjects/OpenCV/OpenCV-android-sdk2/sdk/native/jni/OpenCV.mk

LOCAL_C_INCLUDE :=/home/User/Download/OpenCV-android-sdk2/sdk/native/jni/include
LOCAL_SRC_FILES := native_processing.cpp
LOCAL_LDLIBS +=  -llog -ldl
LOCAL_MODULE:= native_test


include $(BUILD_SHARED_LIBRARY)

 

Error: Warning:Native C/C++ source code is found, but it seems that
NDK option is not configured.  Note that if you have an Android.mk, it is
not used for compilation.  The recommended workaround is to remove the
default jni source code directory by adding:

 android {
    sourceSets {
        main {
            jni.srcDirs = []
        }
    }
}    

to build.gradle, manually compile the code with ndk-build, and then
place the resulting shared object in src/main/jniLibs.
/home/User/AndroidStudioProjects/OpenCV/app/src/main/jni/native_processing.cpp
Information:(1) (Unknown) In file included
/home/User/AndroidStudioProjects/OpenCV/app/src/main/jni/native_processing.h
Error:(10, 33) opencv2/core/core.hpp: No such file or directory
compilation terminated.
make: ***
 [/home/User/AndroidStudioProjects/OpenCV/app/build/intermediates/ndk/debug/obj/local/arm64-v8a/objs/app//home/geison/AndroidStudioProjects/OpenCV/app/src/main/jni/native_processing.o] Error 1
:app:compileDebugNdk FAILED
Error:Execution failed for task ':app:compileDebugNdk'.
com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process 'command '/home/User/Android/Sdk/ndk-bundle/ndk-build'' finished with non-zero exit value 2

- user1590438

---

嗨，Geison，我也遇到了同样的问题。你能帮我解决吗？ - LuminiousAndroid

Answer 1

如果有的话，请在build.gradle中注释掉以下内容：

externalNativeBuild {
        cmake {
            path "CMakeLists.txt"
        }
    }

将此代码添加到gradle中：

sourceSets.main {
    jni.srcDirs = [] //disable automatic ndk-build call
}

- M. Usman Khan

Answer 2

你尝试过仅使用#include <opencv2/core.hpp>而非#include <opencv2/core/core.hpp>吗？这对我有效（在ubuntu 14.04和opencv 2.4下）。

- bdanos

---

我在 build.gradle 中添加了以下代码：android { sourceSets { main { jni.srcDirs = [] } } }它可以正常工作！ - user1590438

Answer 3

包含的OpenCV.mk为您定义了包含路径，因此在Include之后不要尝试重新定义它。此外，您可能更喜欢OPENCV_LIB_TYPE：= STATIC，因此请稍微清理一下Android.mk文件：

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)
OPENCV_CAMERA_MODULES:=on
OPENCV_LIB_TYPE:=STATIC
include /home/User/AndroidStudioProjects/OpenCV/OpenCV-android-sdk2/sdk/native/jni/OpenCV.mk

LOCAL_SRC_FILES := native_processing.cpp
LOCAL_LDLIBS +=  -llog -ldl
LOCAL_MODULE:= native_test

include $(BUILD_SHARED_LIBRARY)

你真的使用相机模块吗？

- Alex Cohn

---

没有生效。如果我去掉OpenCV的#include引用（#include <opencv2/core/core.hpp> <opencv2/imgproc/imgproc.hpp> <opencv2/features2d/features2d.hpp>）...编译器会在$include <vector>处报错...我认为问题不在OpenCV上。 - user1590438

你在 Application.mk 中定义了 APP_STL 吗？请发布 ndk-build V=1 的输出结果。 - Alex Cohn

但是，如果您使用Gradle插件来构建.so文件而不是ndk-build，则您的Android.mk文件无关紧要。重要的是build.gradle文件的内容。 - Alex Cohn