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Android NDK开发:Opencv实现戴口罩识别

Android NDK开发:Opencv实现戴口罩识别

作者: itfitness | 来源:发表于2022-12-19 18:25 被阅读0次

    目录

    效果展示

    相关文章及项目

    这里的程序是以我的这篇文章为基础的:Android NDK开发:Opencv实现人脸识别
    这里我参考了这个项目:https://github.com/hpc203/FaceMaskDetection-dnn,用的这个项目里面的C语言部分的代码和dnn模型数据,移植到了Android上

    实现步骤

    1.创建人脸框类

    这里创建一个用于存储人脸框和是否佩戴口罩的类用于绘制

    public class FaceMaskBean {
        private int isMask = 0;//是否戴口罩了,0没戴,1戴了
        private Rect faceRect;//人脸框
    
        public FaceMaskBean(int isMask, Rect faceRect) {
            this.isMask = isMask;
            this.faceRect = faceRect;
        }
    
        public int getIsMask() {
            return isMask;
        }
    
        public void setIsMask(int isMask) {
            this.isMask = isMask;
        }
    
        public Rect getFaceRect() {
            return faceRect;
        }
    
        public void setFaceRect(Rect faceRect) {
            this.faceRect = faceRect;
        }
    }
    
    2.修改JNI返回类型

    Android NDK开发:Opencv实现人脸识别中的代码相比,修改NativeUtil中ndkCheckFace函数的返回类型为FaceMaskBean类型的数组

    object NativeUtil {
        init {
            System.loadLibrary("NDKInterface")
            System.loadLibrary("opencv_java4")
        }
    
        /**
         * 加载模型
         */
        external fun ndkInit(protoTxtFilePath:String,modelFilePath:String)
    
        /**
         * 人脸检测
         */
        external fun ndkCheckFace(yuvData:ByteArray,rotation:Int,width:Int,height:Int):Array<FaceMaskBean>
    }
    
    3.移植戴口罩识别代码

    这里我把文章开头提到的项目中的代码做了如下修改
    FaceMask.h

    #ifndef OPENCVCHECKFACE_FACEMASK_H
    #define OPENCVCHECKFACE_FACEMASK_H
    #include <iostream>
    #include <opencv2/dnn.hpp>
    #include <opencv2/imgproc.hpp>
    #include <opencv2/highgui.hpp>
    #include <math.h>
    #include <jni.h>
    using namespace cv;
    using namespace dnn;
    using namespace std;
    
    class FaceMask {
    public:
        FaceMask(const float conf_thresh = 0.5, const float iou_thresh = 0.4);
        jobjectArray detect(Mat &srcimg,JNIEnv* &env);
    private:
        const int feature_map_sizes[5][2] = {{33, 33}, {17, 17}, {9, 9}, {5, 5}, {3, 3}};
        const float anchor_sizes[5][2] = {{0.04, 0.056}, {0.08, 0.11}, {0.16, 0.22}, {0.32, 0.45}, {0.64, 0.72}};
        const float anchor_ratios[3] = {1, 0.62, 0.42};
        const float variances[4] = {0.1, 0.1, 0.2, 0.2};
        float conf_thresh;
        float iou_thresh;
        const Size target_shape = Size(260, 260);
        const int num_prior = 5972;
        float* prior_data;
        Net net;
    
        void generate_priors();
        void decode(Mat loc, Mat conf, vector<Rect>& boxes, vector<float>& confidences, vector<int>& classIds, const int srcimg_h, const int srcimg_w);
    };
    
    
    #endif //OPENCVCHECKFACE_FACEMASK_H
    
    

    FaceMask.cpp,其中模型数据我为了方便直接手动拷贝到了SD卡中,然后直接用路径加载的

    #include "FaceMask.h"
    
    FaceMask::FaceMask(const float conf_thresh, const float iou_thresh)
    {
        this->conf_thresh = conf_thresh;
        this->iou_thresh = iou_thresh;
        this->net = readNet("/storage/emulated/0/Android/data/com.itfitness.opencvcheckface/files/Download/face_mask_detection.caffemodel"
                , "/storage/emulated/0/Android/data/com.itfitness.opencvcheckface/files/Download/face_mask_detection.prototxt");
        this->generate_priors();
    }
    
    void FaceMask::generate_priors()
    {
        this->prior_data = new float[this->num_prior *4];
        float* pdata = prior_data;
        int i = 0, j = 0, h = 0, w = 0;
        float height = 0, width = 0, ratio = 0;
        for (i = 0; i < 5; i++)
        {
            const int feature_map_height = this->feature_map_sizes[i][0];
            const int feature_map_width = this->feature_map_sizes[i][1];
            for (h = 0; h < feature_map_height; h++)
            {
                for (w = 0; w < feature_map_width; w++)
                {
                    ratio = sqrt(this->anchor_ratios[0]);
                    for(j=0;j<2;j++)
                    {
                        width = this->anchor_sizes[i][j] * ratio;
                        height = this->anchor_sizes[i][j] / ratio;
    //                    pdata[0] = (w + 0.5) / feature_map_width - 0.5 * width;       ///xmin
    //                    pdata[1] = (h + 0.5) / feature_map_height - 0.5 * height;      ////ymin
    //                    pdata[2] = (w + 0.5) / feature_map_width + 0.5 * width;       ///xmax
    //                    pdata[3] = (h + 0.5) / feature_map_height + 0.5 * height;      ////ymax
                        pdata[0] = (w + 0.5) / feature_map_width;       ///center_x
                        pdata[1] = (h + 0.5) / feature_map_height;      ////center_y
                        pdata[2] = width;       ///width
                        pdata[3] = height;      ////height
                        pdata += 4;
                    }
    
                    for(j=0;j<2;j++)
                    {
                        ratio = sqrt(this->anchor_ratios[j+1]);
                        width = this->anchor_sizes[i][0] * ratio;
                        height = this->anchor_sizes[i][0] / ratio;
    //                    pdata[0] = (w + 0.5) / feature_map_width - 0.5 * width;       ///xmin
    //                    pdata[1] = (h + 0.5) / feature_map_height - 0.5 * height;      ////ymin
    //                    pdata[2] = (w + 0.5) / feature_map_width + 0.5 * width;       ///xmax
    //                    pdata[3] = (h + 0.5) / feature_map_height + 0.5 * height;      ////ymax
                        pdata[0] = (w + 0.5) / feature_map_width;       ///center_x
                        pdata[1] = (h + 0.5) / feature_map_height;      ////center_y
                        pdata[2] = width;       ///width
                        pdata[3] = height;      ////height
                        pdata += 4;
                    }
                }
            }
        }
    }
    
    void FaceMask::decode(Mat loc, Mat conf, vector<Rect>& boxes, vector<float>& confidences, vector<int>& classIds, const int srcimg_h, const int srcimg_w)
    {
        if(loc.dims==3)
        {
            loc = loc.reshape(0, this->num_prior);
        }
        if(conf.dims==3)
        {
            conf = conf.reshape(0, this->num_prior);
        }
        float predict_xmin = 0, predict_ymin = 0, predict_w = 0, predict_h = 0;
        int srcimg_xmin = 0, srcimg_ymin = 0;
        int i = 0;
        for(i=0;i<this->num_prior;i++)
        {
            Mat scores = conf.row(i).colRange(0, 2);
            Point classIdPoint;
            double score;
            // Get the value and location of the maximum score
            minMaxLoc(scores, 0, &score, 0, &classIdPoint);
            if (score>this->conf_thresh)
            {
                const int row_ind = i * 4;
                const float* pbox = (float*)loc.data + row_ind;
                predict_w = exp(pbox[2] * this->variances[2]) * this->prior_data[row_ind + 2];
                predict_h = exp(pbox[3] * this->variances[3]) * this->prior_data[row_ind + 3];
                predict_xmin = pbox[0] * this->variances[0] * this->prior_data[row_ind + 2] + this->prior_data[row_ind] - 0.5 * predict_w;
                predict_ymin = pbox[1] * this->variances[1] * this->prior_data[row_ind + 3] + this->prior_data[row_ind + 1] - 0.5 * predict_h;
                classIds.push_back(classIdPoint.x);
                confidences.push_back(score);
                srcimg_xmin = (int)max(predict_xmin * srcimg_w, 0.f);
                srcimg_ymin = (int)max(predict_ymin * srcimg_h, 0.f);
                boxes.push_back(Rect(srcimg_xmin, srcimg_ymin, (int)(predict_w * srcimg_w), (int)(predict_h * srcimg_h)));
            }
        }
    }
    
    jobjectArray FaceMask::detect(Mat &srcimg,JNIEnv* &env)
    {
        int height = srcimg.rows;
        int width = srcimg.cols;
        Mat blob = blobFromImage(srcimg, 1/255.0, this->target_shape);
        this->net.setInput(blob);
        vector<Mat> outs;
        this->net.forward(outs, this->net.getUnconnectedOutLayersNames());
        ////post process
        vector<int> classIds;
        vector<float> confidences;
        vector<Rect> boxes;
        this->decode(outs[0], outs[1], boxes, confidences, classIds, height, width);
        vector<int> indices;
        NMSBoxes(boxes, confidences, this->conf_thresh, this->iou_thresh, indices);
    
    
        jclass faceMaskBeanCls = env->FindClass("com/itfitness/opencvcheckface/FaceMaskBean");
        jmethodID faceMaskBean_construct = env->GetMethodID(faceMaskBeanCls, "<init>","(ILandroid/graphics/Rect;)V"); //Rect的构造函数
    
        jclass rectCls = env->FindClass("android/graphics/Rect");
        jmethodID rect_construct = env->GetMethodID(rectCls, "<init>", "(IIII)V"); //Rect的构造函数
        jobjectArray faceRectArray = env->NewObjectArray(indices.size(),faceMaskBeanCls,nullptr);
    
        for (size_t i = 0; i < indices.size(); ++i)
        {
            int idx = indices[i];
            Rect box = boxes[idx];
            if(classIds[idx]==1)
            {
    //            rectangle(srcimg, Point(box.x, box.y), Point(box.x + box.width, box.y + box.height), Scalar(0, 0, 255), 2);
    //            putText(srcimg, "No mask", Point(box.x, box.y -10), FONT_HERSHEY_SIMPLEX, 0.75, Scalar(0, 0, 255), 1);
                jobject rect = env->NewObject(rectCls,rect_construct,box.x,box.y,box.x + box.width,box.y + box.height);
                jobject faceMaskBean = env->NewObject(faceMaskBeanCls,faceMaskBean_construct,0,rect);
                env->SetObjectArrayElement(faceRectArray,i,faceMaskBean);
            }
            else
            {
    //            rectangle(srcimg, Point(box.x, box.y), Point(box.x + box.width, box.y + box.height), Scalar(0, 255, 0), 2);
    //            putText(srcimg, "wear mask", Point(box.x, box.y -10), FONT_HERSHEY_SIMPLEX, 0.75, Scalar(0, 255, 0), 1);
                jobject rect = env->NewObject(rectCls,rect_construct,box.x,box.y,box.x + box.width,box.y + box.height);
                jobject faceMaskBean = env->NewObject(faceMaskBeanCls,faceMaskBean_construct,1,rect);
                env->SetObjectArrayElement(faceRectArray,i,faceMaskBean);
            }
        }
        return faceRectArray;
    }
    

    NDK的ndkCheckFace函数也进行了修改,如下所示:

    extern "C"
    JNIEXPORT jobjectArray JNICALL
    Java_com_itfitness_opencvcheckface_NativeUtil_ndkCheckFace(JNIEnv *env, jobject thiz,
                                                               jbyteArray yuv_data, jint rotation,jint width,jint height) {
        jbyte *yuvBuffer = (jbyte *) env->GetByteArrayElements(yuv_data, JNI_FALSE);
    
        Mat imageSrc(height + height / 2, width, CV_8UC1, (unsigned char *) yuvBuffer);
    
    
    
        Mat bgrCVFrame;
        cvtColor(imageSrc, bgrCVFrame, cv::COLOR_YUV2BGR_NV21);
    
        rotateMat(bgrCVFrame,rotation);
    
        return modelMask.detect(bgrCVFrame,env);
    }
    

    案例源码

    https://gitee.com/itfitness/opencv-face-mask

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