【opencv】运行opencv3.4中的demo--facial_features.cpp
1.运行opencv3.4中的demo--facial_features.cpp
2.详解opencv中的CommandLineParser类
facial_features.cpp是一个检测人脸、眼睛、鼻子、嘴巴的cpp-demo，涉及到命令行操作，用的是opencv中的CommandLineParser类。facial_features.cpp在..\opencv3_4\opencv\sources\samples\cpp\facial_features.cpp 目录下。
1.运行opencv3.4中的demo--facial_features.cpp
【操作方法】
1.配置属性
配置属性==>调试==>命令参数：hebe2.jpg haarcascade_frontalface_alt.xml -eyes=haarcascade_eye.xml -noses=haarcascade_mcs_nose.xml -mouth=haarcascade_mcs_mouth.xml
注意：
1.每个命令参数之间用空格隔开；
2.上述路径实际是参数的路径，而不只是参数名称。例如，上述第一个参数 hebe2.jpg（实际上我将该图片文件放置在工程文件目录下了，所以可以省略路径）
如果不会设置相对文件路径，就直接将文件绝对路径写下来即可。
例如，hebe2.jpg的存放位置为"d:\opencv3_4\data\hebe2.jpg",则可以将上述第一个参数写为d:\opencv3_4\data\hebe2.jpg
同理，第二个参数的绝对路径为："d:\opencv3_4\xml\haarcascade_frontalface_alt.xml" ，则可将第二个参数写为：d:\opencv3_4\xml\haarcascade_frontalface_alt.xml
用绝对路径的配置方法为：
配置属性==>调试==>命令参数：d:\opencv3_4\data\hebe2.jpg d:\opencv3_4\xml\haarcascade_frontalface_alt.xml -eyes=d:\opencv3_4\xml\haarcascade_eye.xml -noses=d:\opencv3_4\xml\haarcascade_mcs_nose.xml -mouth=d:\opencv3_4\xml\haarcascade_mcs_mouth.xml
运行程序的参数打印输出的结果如下：
2.修改程序
将源程序中的利用命令行获取路径的方式修改一下：
把这两行替换掉： input_image_path = parser.get<string>(0);
face_cascade_path = parser.get<string>(1);
替换为：input_image_path = argv[1];
face_cascade_path = argv[2];
//input_image_path = parser.get<string>(0); //face_cascade_path = parser.get<string>(1); input_image_path = argv[1]; face_cascade_path = argv[2];
因为，若运行原程序中的获取路径方式，会报错如下：（在没搞清楚原因的情况下，改为上述方式，可使得程序正常运行。）
3.运行结果：
从结果看，face、eyes、nose、mouth都检测出来了。
【程序代码+注释】
//facial_features.cpp: 定义控制台应用程序的入口点。
#include "stdafx.h"
/*
* Author: Samyak Datta (datta[dot]samyak[at]gmail.com)
*
* A program to detect facial feature points using
* Haarcascade classifiers for face, eyes, nose and mouth
*
*/
#include "opencv2/objdetect.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/imgproc.hpp"
#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
using namespace cv;
// Functions for facial feature detection
static void help();
static void detectFaces(Mat&, vector<Rect_<int> >&, string);
static void detectEyes(Mat&, vector<Rect_<int> >&, string);
static void detectNose(Mat&, vector<Rect_<int> >&, string);
static void detectMouth(Mat&, vector<Rect_<int> >&, string);
static void detectFacialFeaures(Mat&, const vector<Rect_<int> >, string, string, string);
string input_image_path;
string face_cascade_path, eye_cascade_path, nose_cascade_path, mouth_cascade_path;
int main(int argc, char** argv)
{
cv::CommandLineParser parser(argc, argv, "{eyes||}{nose||}{mouth||}{help h||}"); // 构造函数初始化
for (int i = 0;i < argc;i++) //打印参数信息
{
cout << argv[i] << endl;
}
if (parser.has("help"))
{
help();
return 0;
}
//input_image_path = parser.get<string>(0);
//face_cascade_path = parser.get<string>(1);
input_image_path = argv[1];
face_cascade_path = argv[2];
eye_cascade_path = parser.has("eyes") ? parser.get<string>("eyes") : ""; //通过参数名称获取 参数
nose_cascade_path = parser.has("nose") ? parser.get<string>("nose") : "";
mouth_cascade_path = parser.has("mouth") ? parser.get<string>("mouth") : "";
if (input_image_path.empty() || face_cascade_path.empty())
{
cout << "IMAGE or FACE_CASCADE are not specified";
return 1;
}
// Load image and cascade classifier files
Mat image;
image = imread(input_image_path); //读取图片
// Detect faces and facial features
vector<Rect_<int> > faces;
detectFaces(image, faces, face_cascade_path); //检测人脸
detectFacialFeaures(image, faces, eye_cascade_path, nose_cascade_path, mouth_cascade_path); //检测人脸特征
imshow("Result", image);
waitKey(0);
return 0;
}
static void help() //包含程序的使用说明和例子
{
cout << "\nThis file demonstrates facial feature points detection using Haarcascade classifiers.\n"
"The program detects a face and eyes, nose and mouth inside the face."
"The code has been tested on the Japanese Female Facial Expression (JAFFE) database and found"
"to give reasonably accurate results. \n";
cout << "\nUSAGE: ./cpp-example-facial_features [IMAGE] [FACE_CASCADE] [OPTIONS]\n"
"IMAGE\n\tPath to the image of a face taken as input.\n"
"FACE_CASCSDE\n\t Path to a haarcascade classifier for face detection.\n"
"OPTIONS: \nThere are 3 options available which are described in detail. There must be a "
"space between the option and it's argument (All three options accept arguments).\n"
"\t-eyes=<eyes_cascade> : Specify the haarcascade classifier for eye detection.\n"
"\t-nose=<nose_cascade> : Specify the haarcascade classifier for nose detection.\n"
"\t-mouth=<mouth-cascade> : Specify the haarcascade classifier for mouth detection.\n";
cout << "EXAMPLE:\n"
"(1) ./cpp-example-facial_features image.jpg face.xml -eyes=eyes.xml -mouth=mouth.xml\n"
"\tThis will detect the face, eyes and mouth in image.jpg.\n"
"(2) ./cpp-example-facial_features image.jpg face.xml -nose=nose.xml\n"
"\tThis will detect the face and nose in image.jpg.\n"
"(3) ./cpp-example-facial_features image.jpg face.xml\n"
"\tThis will detect only the face in image.jpg.\n";
cout << " \n\nThe classifiers for face and eyes can be downloaded from : "
" \nhttps://github.com/opencv/opencv/tree/master/data/haarcascades";
cout << "\n\nThe classifiers for nose and mouth can be downloaded from : "
" \nhttps://github.com/opencv/opencv_contrib/tree/master/modules/face/data/cascades\n";
}
static void detectFaces(Mat& img, vector<Rect_<int> >& faces, string cascade_path)
{
CascadeClassifier face_cascade;
face_cascade.load(cascade_path);
face_cascade.detectMultiScale(img, faces, 1.15, 3, 0 | CASCADE_SCALE_IMAGE, Size(30, 30)); //多尺度检测人脸
return;
}
static void detectFacialFeaures(Mat& img, const vector<Rect_<int> > faces, string eye_cascade,
string nose_cascade, string mouth_cascade)
{
for (unsigned int i = 0; i < faces.size(); ++i)
{
// Mark the bounding box enclosing the face
Rect face = faces[i];
rectangle(img, Point(face.x, face.y), Point(face.x + face.width, face.y + face.height), //用矩形框标记出人脸
Scalar(255, 0, 0), 1, 4);
// Eyes, nose and mouth will be detected inside the face (region of interest)
Mat ROI = img(Rect(face.x, face.y, face.width, face.height));
// Check if all features (eyes, nose and mouth) are being detected
bool is_full_detection = false;
if ((!eye_cascade.empty()) && (!nose_cascade.empty()) && (!mouth_cascade.empty()))
is_full_detection = true;
// Detect eyes if classifier provided by the user
if (!eye_cascade.empty()) // 人眼检测
{
vector<Rect_<int> > eyes;
detectEyes(ROI, eyes, eye_cascade); // 人眼检测
// Mark points corresponding to the centre of the eyes
for (unsigned int j = 0; j < eyes.size(); ++j)
{
Rect e = eyes[j];
circle(ROI, Point(e.x + e.width / 2, e.y + e.height / 2), 3, Scalar(0, 255, 0), -1, 8); //用圆形 标记出眼睛
/* rectangle(ROI, Point(e.x, e.y), Point(e.x+e.width, e.y+e.height),
Scalar(0, 255, 0), 1, 4); */
}
}
// Detect nose if classifier provided by the user
double nose_center_height = 0.0;
if (!nose_cascade.empty()) // 鼻子检测
{
vector<Rect_<int> > nose;
detectNose(ROI, nose, nose_cascade);
// Mark points corresponding to the centre (tip) of the nose
for (unsigned int j = 0; j < nose.size(); ++j)
{
Rect n = nose[j];
circle(ROI, Point(n.x + n.width / 2, n.y + n.height / 2), 3, Scalar(0, 255, 0), -1, 8); //用圆形 标记出鼻子
nose_center_height = (n.y + n.height / 2);
}
}
// Detect mouth if classifier provided by the user
double mouth_center_height = 0.0;
if (!mouth_cascade.empty()) // 嘴巴检测
{
vector<Rect_<int> > mouth;
detectMouth(ROI, mouth, mouth_cascade);
for (unsigned int j = 0; j < mouth.size(); ++j)
{
Rect m = mouth[j];
mouth_center_height = (m.y + m.height / 2);
// The mouth should lie below the nose
if ((is_full_detection) && (mouth_center_height > nose_center_height)) // 检验鼻子比嘴巴高
{
rectangle(ROI, Point(m.x, m.y), Point(m.x + m.width, m.y + m.height), Scalar(0, 255, 0), 1, 4); //用矩形框标记出嘴巴
}
else if ((is_full_detection) && (mouth_center_height <= nose_center_height))
continue;
else
rectangle(ROI, Point(m.x, m.y), Point(m.x + m.width, m.y + m.height), Scalar(0, 255, 0), 1, 4);
}
}
}
return;
}
static void detectEyes(Mat& img, vector<Rect_<int> >& eyes, string cascade_path)
{
CascadeClassifier eyes_cascade;
eyes_cascade.load(cascade_path);
eyes_cascade.detectMultiScale(img, eyes, 1.20, 5, 0 | CASCADE_SCALE_IMAGE, Size(30, 30));
return;
}
static void detectNose(Mat& img, vector<Rect_<int> >& nose, string cascade_path)
{
CascadeClassifier nose_cascade;
nose_cascade.load(cascade_path);
nose_cascade.detectMultiScale(img, nose, 1.20, 5, 0 | CASCADE_SCALE_IMAGE, Size(30, 30));
return;
}
static void detectMouth(Mat& img, vector<Rect_<int> >& mouth, string cascade_path)
{
CascadeClassifier mouth_cascade;
mouth_cascade.load(cascade_path);
mouth_cascade.detectMultiScale(img, mouth, 1.20, 5, 0 | CASCADE_SCALE_IMAGE, Size(30, 30));
return;
}
【后续】笔者又调皮了一下，将程序作了如下修改
1.将keys的值添加了“{ faces ||}”，所以变为：
cv::CommandLineParser parser(argc, argv, "{faces||}{eyes||}{nose||}{mouth||}{help h||}"); // 构造函数初始化
这是因为，commandLineParse类中的key的定义方式是
// parse keys 解析key值
std::vector<String> k = impl->split_range_string(keys, '{', '}'); //用“{ }”来分割keys
...
std::vector<String> l = impl->split_string(k[i], '|', true); // 用“ | ”来分割开key[i]
// parse argv 解析命令行参数
String s(argv[i]);
bool hasSingleDash = s.length() > 1 && s[0] == '-'; // 用key的方式定义参数，需要在前面加“-”
2.并且将命令行参数中的face.xml文件前，添加了“-faces"，所以第二个命令行参数变为：
“-faces=haarcascade_frontalface_alt.xml ”
3.同时更改回程序：读取第二个参数的方式
//face_cascade_path = argv[2];
face_cascade_path= parser.has("faces") ? parser.get<string>("faces") : "";
4.然后，点击运行，发现OK！
【待解决问题】
通过阅读源代码，发现程序（隐含的）第0个参数，即源程序的路径，opencv中的commandLineParse类的读取第一个参数的方式是
// path to application
size_t pos_s = String(argv[0]).find_last_of("/\\"); //通过寻找argv[0]里的最后一个双斜杠“\\”，来找程序的名称 （.exe程序）
而，通过运行程序显示出来的argv[0]为：
发现不带双斜杠“\\”，所以可能造成opencv的commandLineParse类无法读取第0个参数。所以出现开始时的错误情况。这种方法可通过修改opencv源码的方式解决，改为“\”，使二者匹配；或者更改程序本身的源程序路径改为“\\”式样，使得二者匹配，也可。但我不会改，所以只是先到此为止，发现了问题，留待厉害的大神来指点一二吧！
2.详解opencv中的CommandLineParser类
CommandLineParser类的成员变量和函数如下：
class CV_EXPORTS CommandLineParser
{
public:
CommandLineParser(int argc, const char* const argv[], const String& keys); //构造函数
CommandLineParser(const CommandLineParser& parser); //构造函数
CommandLineParser& operator = (const CommandLineParser& parser);
~CommandLineParser(); //析构函数
String getPathToApplication() const; // 返回应用程序路径 Returns application path
template <typename T>
T get(const String& name, bool space_delete = true) const //通过参数名称获取参数 Access arguments by name
{
T val = T();
getByName(name, space_delete, ParamType<T>::type, (void*)&val); //调用成员函数getByName
return val;
}
/*
String keys = "{@arg1||}{@arg2||}"
String val_1 = parser.get<String>(0); // returns "abc", arg1
String val_2 = parser.get<String>(1); // returns "qwe", arg2
*/
template <typename T>
T get(int index, bool space_delete = true) const //通过索引访问位置参数 Access positional arguments by index
{
T val = T();
getByIndex(index, space_delete, ParamType<T>::type, (void*)&val); //调用成员函数getByIndex
return val;
}
/* Check if field was provided in the command line */
bool has(const String& name) const; //检查该参数是否 在命令行中
/** @brief Check for parsing errors
Returns true if error occurred while accessing the parameters (bad conversion, missing arguments,
etc.). Call @ref printErrors to print error messages list.
*/
bool check() const; // 检查在获取参数时是否有错误发生，若发生error，则打印error信息
/** @brief Set the about message
The about message will be shown when @ref printMessage is called, right before arguments table.
*/
void about(const String& message);
/** @brief Print help message
This method will print standard help message containing the about message and arguments description.
@sa about */
void printMessage() const; //打印help信息
/** @brief Print list of errors occurred
@sa check */
void printErrors() const;
protected:
void getByName(const String& name, bool space_delete, int type, void* dst) const;
void getByIndex(int index, bool space_delete, int type, void* dst) const;
struct Impl;
Impl* impl;
};
特将CommandLineParse类的构造函数附上：
CommandLineParser::CommandLineParser(int argc, const char* const argv[], const String& keys)
{
impl = new Impl;
impl->refcount = 1;
// path to application
size_t pos_s = String(argv[0]).find_last_of("/\\");
if (pos_s == String::npos)
{
impl->path_to_app = "";
impl->app_name = String(argv[0]);
}
else
{
impl->path_to_app = String(argv[0]).substr(0, pos_s);
impl->app_name = String(argv[0]).substr(pos_s + 1, String(argv[0]).length() - pos_s);
}
impl->error = false;
impl->error_message = "";
// parse keys
std::vector<String> k = impl->split_range_string(keys, '{', '}');
int jj = 0;
for (size_t i = 0; i < k.size(); i++)
{
std::vector<String> l = impl->split_string(k[i], '|', true);
CommandLineParserParams p;
p.keys = impl->split_string(l[0]);
p.def_value = l[1];
p.help_message = cat_string(l[2]);
p.number = -1;
if (p.keys.size() <= 0)
{
impl->error = true;
impl->error_message = "Field KEYS could not be empty\n";
}
else
{
if (p.keys[0][0] == '@')
{
p.number = jj;
jj++;
}
impl->data.push_back(p);
}
}
// parse argv
jj = 0;
for (int i = 1; i < argc; i++)
{
String s(argv[i]);
bool hasSingleDash = s.length() > 1 && s[0] == '-';
if (hasSingleDash)
{
bool hasDoubleDash = s.length() > 2 && s[1] == '-';
String key = s.substr(hasDoubleDash ? 2 : 1);
String value = "true";
size_t equalsPos = key.find('=');
if(equalsPos != String::npos) {
value = key.substr(equalsPos + 1);
key = key.substr(0, equalsPos);
}
impl->apply_params(key, value);
}
else
{
impl->apply_params(jj, s);
jj++;
}
}
impl->sort_params();
}
希望大神能解决我上述未解决的问题，欢迎留言！欢迎指正！
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参考：
https://blog.csdn.net/longji/article/details/78206901