MainCarRemoteControl/app/src/main/cpp/traffic_light.cpp

//
// Created by UnknownObject on 2022/9/21.
// Copyright (c) 2022 UnknownNetworkService. All rights reserved.
//

//交通灯识别

#include "traffic_light.h"

namespace uns
{
	//取三个数中的最大值
	int TrafficLight::tri_max(int a, int b, int c)
	{
		return std::max(std::max(a, b), c);
	}
	
	//根据亮度获取亮起的灯的位置
	cv::Mat TrafficLight::GetLight(const cv::Mat &img)
	{
		cv::Mat hsv;
		cv::cvtColor(img, hsv, cv::COLOR_BGR2HSV);
		cv::Mat chn_v(hsv.size(), CV_8UC1);
		for (int r = 0; r < hsv.rows; r++)
		{
			for (int c = 0; c < hsv.cols; c++)
			{
				uchar v = hsv.at<cv::Vec3b>(r, c)[2];
				chn_v.at<uchar>(r, c) = (v >= 250 ? 0 : 255);
			}
		}
		cv::Mat kernel = cv::getStructuringElement(cv::MORPH_ELLIPSE, cv::Size(11, 11));
		cv::morphologyEx(chn_v, chn_v, cv::MORPH_CLOSE, kernel);
		cv::Rect max_validate_rect = GetMaxRect(chn_v);
		if (max_validate_rect.size().area() == 0)
			return cv::Mat();
		return img(max_validate_rect);
	}
	
	//获取图片中面积最大的轮廓的外接矩形
	cv::Rect TrafficLight::GetMaxRect(const cv::Mat &img)
	{
		cv::Rect max_rect;
		double max_rect_size = 0;
		std::vector<cv::Vec4i> hierarchy;
		std::vector<std::vector<cv::Point>> contours;
		cv::findContours(img, contours, hierarchy, cv::RETR_CCOMP, cv::CHAIN_APPROX_SIMPLE); //轮廓查找
		for (auto &contour: contours) //检测所找到的轮廓
		{
			double area = cv::contourArea(cv::Mat(contour));
			if (area > (img.size().area() / 2.0))
				continue;
			if (area > max_rect_size)
			{
				max_rect_size = area;
				max_rect = cv::boundingRect(contour);
			}
		}
		return max_rect;
	}
	
	//“远大于”函数
	bool TrafficLight::MuchLarger(int a, int b, double rate)
	{
		return (a >= (b * rate));
	}
	
	//识别灯的颜色
	Light::TL_COLOR TrafficLight::GetImageColor(const cv::Mat &img, double rate)
	{
		int cnt_r = 0, cnt_g = 0, cnt_y = 0;
		int cnt_g_less = 0, cnt_b_less = 0;
		for (int r = 0; r < img.rows; r++)
		{
			for (int c = 0; c < img.cols; c++)
			{
				uns::Colors::CVColor color(img.at<cv::Vec3b>(r, c));
				if (MuchLarger(color.GetR(), color.GetG(), rate) &&
					MuchLarger(color.GetR(), color.GetB(), rate))
					cnt_r++;
				else if (MuchLarger(color.GetG(), color.GetR(), rate) &&
						 MuchLarger(color.GetG(), color.GetB(), rate))
					cnt_g++;
				else if (MuchLarger(color.GetB(), color.GetR(), rate) &&
						 MuchLarger(color.GetB(), color.GetG(), rate))
					cnt_g++;
				else if (MuchLarger(color.GetR(), color.GetB(), rate) &&
						 MuchLarger(color.GetG(), color.GetB(), rate))
					cnt_y++;
				if (color.GetG() < 110)
					cnt_g_less++;
				if (color.GetB() < 110)
					cnt_b_less++;
			}
		}
		LOGI("GLess: %d, BLess: %d", cnt_g_less, cnt_b_less);
		int cnt_max = tri_max(cnt_r, cnt_g, cnt_y);
		if ((cnt_max == cnt_r) || (cnt_max == cnt_y))
		{
			if ((cnt_g_less < 50) /*&& (cnt_b_less < 5)*/)
				return Light::TL_COLOR::Yellow;
			else
				return Light::TL_COLOR::Red;
		}
		else if (cnt_max == cnt_g)
			return Light::TL_COLOR::Green;
		else
			return Light::TL_COLOR::Null;
	}
	
	//整合的识别函数
	Light::TL_COLOR TrafficLight::Reco(cv::Mat &img)
	{
		LOGI("Begin Traffic Light");
		img = GetLight(img);
		if (img.empty())
			return Light::TL_COLOR::Null;
		LOGI("Traffic Light Finished");
		cv::imwrite("/sdcard/MainCar/tlr_finished.jpg", img);
		return GetImageColor(img, 1.3);
	}
};

//导出的识别函数
extern "C" JNIEXPORT
jint JNICALL
Java_com_uns_maincar_cpp_1interface_TrafficLight_Recognize(JNIEnv *env, jclass _this, jobject image)
{
	cv::Mat img;
	if(!BitmapToMat(env,image,img))
		return 4;
	cv::imwrite("/sdcard/MainCar/red.jpg", img);
	uns::TrafficLight traffic_light;
	switch(traffic_light.Reco(img))
	{
		case uns::Light::TL_COLOR::Red:
			return 0;
		case uns::Light::TL_COLOR::Yellow:
			return 1;
		case uns::Light::TL_COLOR::Green:
			return 2;
		case uns::Light::TL_COLOR::Null:
			return 3;
	}
	return 5;
}

//导出的自检函数
extern "C" JNIEXPORT
jstring JNICALL
Java_com_uns_maincar_cpp_1interface_EnvTest_TrafficLightTest(JNIEnv *env, jclass _this)
{
	std::string version = "TrafficLightReco Found, Version: " + std::string(TRAFFIC_LIGHT_RECO_VERSION);
	return env->NewStringUTF(version.c_str());
}