安卓NDK开发——基于JNI与NCNN实现深度神经网络口罩佩带检测模型部署
前言
1.这是一个是检测人员是否佩戴口罩的的安卓NDK项目，只检测人脸上是否有口罩是，是于检测是否佩戴标准，比如是否盖住嘴巴和鼻子，是否标准的医用的口罩的模型还在优化训练中。项目源码地址：https://download.csdn.net/download/matt45m/85252239
2.开发环境是win10,IDE是Android studio 北极狐，用到的库有NCNN,OpenCV，NCNN库可以用官方编译好的releases库，也可以按官方文档自己编译。OpenCV用的是nihui大佬简化过的opencv-mobile，大小只有10多M,如果不嫌大也可以用OpenCV官方的版本。测试使用的安卓手机是mate 30 pro ,有测试CPU和GPU两个性能。
3.项目的各种依赖版本：
一、模型训练
1.使用的数据集是开源的人脸口罩数据集：https://github.com/X-zhangyang/Real-World-Masked-Face-Dataset。数据集基本都是标佩戴。
2.所用的模型训练框架是 yolov5 lite ,在移动端上在保证精度的同时，如果能用上GPU加速，速度能达到10FPS以上。
3.把训练好的模型先onnx，简化之后再转ncnn的模型，这个可以参考ncnn的官网，如果觉得麻烦，也可以直接转pnnx之后直接转ncnn。
二、项目部署
1.创建一个Native C++项目
2.把下载好的NCNN和OpenCV so库粘贴到cpp目录下，这里只要arm64-v8a和armeadbi-v7a这两个库，这样的话，项目会小很多，但就是不能在安卓的虚拟机上运行，毕竟ncnn在虚拟机也是跑不动的。
3.添加推理代码
3.1 faceMask.h
#ifndef _FACE_FACEMASK_H_
#define _FACE_FACEMASK_H_
#include "net.h"
#include 3.2 faceMask.cpp
#include "faceMaks.h"
#include 3.3 在原本的jni.cpp文件上添加代码
#include 以上C++部分的代码已添加完成。
4.编写makefile文件
project(photo)
cmake_minimum_required(VERSION 3.4.1)
#导入ncnn库
set(ncnn_DIR ${CMAKE_SOURCE_DIR}/ncnn/${ANDROID_ABI}/lib/cmake/ncnn)
find_package(ncnn REQUIRED)
#导入opencv库
set(OpenCV_DIR ${CMAKE_SOURCE_DIR}/opencv/sdk/native/jni)
find_package(OpenCV REQUIRED core imgproc)
#导入cpp文件
add_library(${PROJECT_NAME} SHARED faceMask.cpp mask_jni.cpp)
target_link_libraries(${PROJECT_NAME} ncnn ${OpenCV_LIBS})
5.添加java接口文件
package com.dashu.photo;
import android.content.res.AssetManager;
import android.graphics.Bitmap;
public class Mask
{
public native boolean Init(AssetManager mgr);
public native Bitmap maskDetect(Bitmap bitmap);
static {
System.loadLibrary("photo");
}
}
6.jave实现代码
package com.dashu.photo;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.media.ExifInterface;
import android.graphics.Matrix;
import java.io.IOException;
import java.io.FileNotFoundException;
public class MainActivity extends Activity
{
private static final int SELECT_IMAGE = 1;
private ImageView imageView;
private Bitmap bitmap = null;
private Bitmap temp = null;
private Bitmap showImage = null;
private Bitmap bitmapCopy = null;
private Bitmap dst = null;
boolean useGPU = true;
private Mask mask = new Mask();
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
imageView = (ImageView) findViewById(R.id.imageView);
boolean ret_init = mask.Init(getAssets());
if (!ret_init)
{
Log.e("MainActivity", "Mask Init failed");
}
//打开图像
ImageButton openFile = (ImageButton) findViewById(R.id.btn_open_images);
openFile.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View arg0)
{
Intent i = new Intent(Intent.ACTION_PICK);
i.setType("image/*");
startActivityForResult(i, SELECT_IMAGE);
}
});
//检测图像
ImageButton image_gray = (ImageButton) findViewById(R.id.btn_detection);
image_gray.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View arg0)
{
if (showImage == null)
{
return;
}
Bitmap bitmap = mask.maskDetect(showImage);
imageView.setImageBitmap(bitmap);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK && null != data) {
Uri selectedImage = data.getData();
try
{
if (requestCode == SELECT_IMAGE)
{
bitmap = decodeUri(selectedImage);
showImage = bitmap.copy(Bitmap.Config.ARGB_8888, true);
bitmapCopy = bitmap.copy(Bitmap.Config.ARGB_8888, true);
imageView.setImageBitmap(bitmap);
}
}
catch (FileNotFoundException e)
{
Log.e("MainActivity", "FileNotFoundException");
return;
}
}
}
private Bitmap decodeUri(Uri selectedImage) throws FileNotFoundException
{
// Decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(getContentResolver().openInputStream(selectedImage), null, o);
// The new size we want to scale to
final int REQUIRED_SIZE = 640;
// Find the correct scale value. It should be the power of 2.
int width_tmp = o.outWidth, height_tmp = o.outHeight;
int scale = 1;
while (true) {
if (width_tmp / 2 < REQUIRED_SIZE
|| height_tmp / 2 < REQUIRED_SIZE) {
break;
}
width_tmp /= 2;
height_tmp /= 2;
scale *= 2;
}
// Decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(selectedImage), null, o2);
// Rotate according to EXIF
int rotate = 0;
try
{
ExifInterface exif = new ExifInterface(getContentResolver().openInputStream(selectedImage));
int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);
switch (orientation) {
case ExifInterface.ORIENTATION_ROTATE_270:
rotate = 270;
break;
case ExifInterface.ORIENTATION_ROTATE_180:
rotate = 180;
break;
case ExifInterface.ORIENTATION_ROTATE_90:
rotate = 90;
break;
}
}
catch (IOException e)
{
Log.e("MainActivity", "ExifInterface IOException");
}
Matrix matrix = new Matrix();
matrix.postRotate(rotate);
return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
}
}
7.布局文件
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<ImageView
android:id="@+id/imageView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
ImageView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageButton
android:id="@+id/btn_open_images"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="@mipmap/open_images" />
<ImageButton
android:id="@+id/btn_detection"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:src="@mipmap/detection" />
LinearLayout>
LinearLayout>
三、项目效果
1.佩戴口罩
2.不佩戴口罩
