git clone https://github.com/ShiqiYu/libfacedetection.git

cmake -DENABLE_NEON=OFF -DCMAKE_BUILD_TYPE=RELEASE .

-- The C compiler identification is GNU 11.3.0
-- The CXX compiler identification is GNU 11.3.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/cc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
BUILD_VERSION:v0.0.3
-- Found OpenMP_C: -fopenmp (found version "4.5") 
-- Found OpenMP_CXX: -fopenmp (found version "4.5") 
-- Found OpenMP: TRUE (found version "4.5")  
-- Performing Test COMPILER_HAS_HIDDEN_VISIBILITY
-- Performing Test COMPILER_HAS_HIDDEN_VISIBILITY - Success
-- Performing Test COMPILER_HAS_HIDDEN_INLINE_VISIBILITY
-- Performing Test COMPILER_HAS_HIDDEN_INLINE_VISIBILITY - Success
-- Performing Test COMPILER_HAS_DEPRECATED_ATTR
-- Performing Test COMPILER_HAS_DEPRECATED_ATTR - Success
CXX_FLAGS:  -O3 -mavx2 -mfma -fopenmp
LINKER_FLAGS:  
AVX512 = OFF
AVX2 = ON
NEON = OFF
OpenMP = TRUE
DEMO = OFF
-- Configuring done
-- Generating done
CMake Warning:
  Manually-specified variables were not used by the project:

    NABLE_NEON


-- Build files have been written to: /home/jason/file/libfacedetection-master

make -j4

[ 25%] Building CXX object CMakeFiles/facedetection.dir/src/facedetectcnn-data.cpp.o
[ 50%] Building CXX object CMakeFiles/facedetection.dir/src/facedetectcnn-model.cpp.o
[ 75%] Building CXX object CMakeFiles/facedetection.dir/src/facedetectcnn.cpp.o
[100%] Linking CXX static library libfacedetection.a
[100%] Built target facedetection

#include <stdio.h>
#include <opencv2/opencv.hpp>
#include "facedetectcnn.h"

//define the buffer size. Do not change the size!
//0x9000 = 1024 * (16 * 2 + 4), detect 1024 face at most
#define DETECT_BUFFER_SIZE 0x9000
using namespace cv;
using namespace std;

int main()
{


	//load an image and convert it to gray (single-channel)
    string img_path = "/home/jason/file/02-use-libfacedetection/cnnresult.png";
    Mat image = imread(img_path);
	if(image.empty())
	{
        printf("Can not load the image file %s.\n", img_path.c_str());
		return -1;
	}

	int * pResults = NULL; 
    //pBuffer is used in the detection functions.
    //If you call functions in multiple threads, please create one buffer for each thread!
    unsigned char * pBuffer = (unsigned char *)malloc(DETECT_BUFFER_SIZE);
    if(!pBuffer)
    {
        fprintf(stderr, "Can not alloc buffer.\n");
        return -1;
    }
	

	///
	// CNN face detection 
	// Best detection rate
	//
	//!!! The input image must be a BGR one (three-channel) instead of RGB
	//!!! DO NOT RELEASE pResults !!!
    TickMeter cvtm;
    cvtm.start();

	pResults = facedetect_cnn(pBuffer, (unsigned char*)(image.ptr(0)), image.cols, image.rows, (int)image.step);
    
    cvtm.stop();    
    printf("time = %gms\n", cvtm.getTimeMilli());
    
    printf("%d faces detected.\n", (pResults ? *pResults : 0));
	Mat result_image = image.clone();
	//print the detection results
	for(int i = 0; i < (pResults ? *pResults : 0); i++)
	{
        short * p = ((short*)(pResults + 1)) + 16*i;
		int confidence = p[0];
		int x = p[1];
		int y = p[2];
		int w = p[3];
		int h = p[4];
        
        //show the score of the face. Its range is [0-100]
        char sScore[256];
        snprintf(sScore, 256, "%d", confidence);
        cv::putText(result_image, sScore, cv::Point(x, y-3), cv::FONT_HERSHEY_SIMPLEX, 0.5, cv::Scalar(0, 255, 0), 1);
        //draw face rectangle
		rectangle(result_image, Rect(x, y, w, h), Scalar(0, 255, 0), 2);
        //draw five face landmarks in different colors
        cv::circle(result_image, cv::Point(p[5], p[5 + 1]), 1, cv::Scalar(255, 0, 0), 2);
        cv::circle(result_image, cv::Point(p[5 + 2], p[5 + 3]), 1, cv::Scalar(0, 0, 255), 2);
        cv::circle(result_image, cv::Point(p[5 + 4], p[5 + 5]), 1, cv::Scalar(0, 255, 0), 2);
        cv::circle(result_image, cv::Point(p[5 + 6], p[5 + 7]), 1, cv::Scalar(255, 0, 255), 2);
        cv::circle(result_image, cv::Point(p[5 + 8], p[5 + 9]), 1, cv::Scalar(0, 255, 255), 2);
        
        //print the result
        printf("face %d: confidence=%d, [%d, %d, %d, %d] (%d,%d) (%d,%d) (%d,%d) (%d,%d) (%d,%d)\n", 
                i, confidence, x, y, w, h, 
                p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13],p[14]);

	}
	imshow("result", result_image);

	waitKey();

    //release the buffer
    free(pBuffer);

	return 0;
}