实现python 调用 C++ 接口的 easypr
本文实现了用python 调用 C++ 的easypr ,实现车牌的识别. CMakelist.txt 以及调用方法将会附上
CMakelist.txt, 需要 注意 add_definitions(-fPIC) ,因为没有这句导致动态链接库编译失败,而且在easypr的编译中也要加上这句.
cmake_minimum_required(VERSION 3.0.0)
project(py_plate_locate)
#动态链接库因为没有加这个而失败
add_definitions(-fPIC)
# c++11 required
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
# set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "/home/k/SoftWare/opencv-3.1.0/build")
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "/home/k/SoftWare/opencv-3.2.0/build")
# OpenVC3 required
find_package(OpenCV3.2 REQUIRED)
# where to find header files
set(EASYPR_INCLUDE_DIRS "../include" )
#find include file
include_directories(.)
include_directories(${EASYPR_INCLUDE_DIRS})
include_directories(${OpenCV_INCLUDE_DIRS})
#find lib file path
link_directories(easypr "../build")
link_directories(thirdparty "../build/thirdparty")
# sub directories
#add_subdirectory(thirdparty easypr)
if (CMAKE_SYSTEM_NAME MATCHES "Darwin")
set(EXECUTABLE_NAME "py_plate_locate")
elseif (CMAKE_SYSTEM_NAME MATCHES "Linux")
set(EXECUTABLE_NAME "py_plate_locate")
endif ()
#"main.cpp"
set(SOURCE_FILES "py_plate_detector.cpp")
# set to be releas mode
# set(CMAKE_BUILD_TYPE Release)
# test cases 生成可执行文件
# add_executable(${EXECUTABLE_NAME} ${SOURCE_FILES})
#生成静态库
# add_library(${EXECUTABLE_NAME} STATIC ${SOURCE_FILES})
#生成动态库
add_library(${EXECUTABLE_NAME} SHARED ${SOURCE_FILES})
# link opencv& easypr libs
target_link_libraries(${EXECUTABLE_NAME} easypr thirdparty ${OpenCV_LIBS})
# MESSAGE(${CMAKE_BINARY_DIR}/../)
SET_TARGET_PROPERTIES(${EXECUTABLE_NAME} PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/../")
#SET_TARGET_PROPERTIES(${EXECUTABLE_NAME} PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/../")
C++ 部分 头文件:py_plate_detector.h
#ifndef PLATE_DETER_H
#define PLATE_DETER_H
#include <iostream>
#include <cstring>
#include "opencv2/opencv.hpp"
#include <easypr.h>
#include <algorithm>
#include<ctime>
extern "C"{
using namespace std;
using namespace cv;
using namespace easypr;
struct OutRec{
int locate[200];
};
unsigned int plate_recog(int height,int width, uchar* frame_data, OutRec &out);
}
#endifc++ 实现部分 py_plate_detector.cpp
#include "py_plate_detector.h"
unsigned int plate_recog(int height,int width, uchar* frame_data,OutRec &out){
//convert image for python type
cv::Mat image(height,width,CV_8UC3);
uchar* pxvec = image.ptr<uchar>(0);
int count = 0;
for(int row = 0; row < height; row++){
pxvec = image.ptr<uchar>(row);
for(int col = 0; col < width; col++){
for(int c = 0; c < 3; c++){
pxvec[col*3+c] = frame_data[count];
count++;
}
}
}
// using easypr to locate the plate
easypr::CPlateRecognize pr;
pr.setResultShow(false);
pr.setDetectType(easypr::PR_DETECT_CMSER);
vector<easypr::CPlate> plateVec;
int result = pr.plateRecognize(image, plateVec);
if (result != 0) return -1;
size_t num = plateVec.size();
// unsigned char * data = new unsigned char[4*num];
// vector<unsigned int> out_;
// memset(data,0, 4*num*sizeof(char));
// printf("num %d\n", num);
for (size_t j = 0; j < num; j++)
{
CPlate temp_plate = plateVec[j];
// imshow("plate_locate", temp_plate.getPlateMat());
RotatedRect rect = temp_plate.getPlatePos();
if (rect.size.height > rect.size.width)
{
std::swap(rect.size.height, rect.size.width);
}
int y_off_set = rect.size.height / 2;
int x_off_set = rect.size.width / 2;
Point2i left_P;
Point2i right_P;
left_P.x = rect.center.x - x_off_set;
left_P.y = rect.center.y - y_off_set;
right_P.x = rect.center.x + x_off_set;
right_P.y = rect.center.y + y_off_set;
Point2i corp_left_P = left_P;
Point2i corp_right_P = right_P;
corp_left_P.y = std::max(int(0), int(left_P.y - 4 * rect.size.height));
corp_right_P.y = left_P.y;
// cout << "corp_left_P" << corp_left_P << endl;
// cout << "corp_right_P" << corp_right_P << endl;
if(corp_left_P.y <0 ) continue;
if(corp_left_P.x <0) continue;
if(corp_right_P.y <0) continue;
if(corp_right_P.x <0) continue;
if(std::abs(corp_left_P.y - corp_right_P.y) < 50) continue;
if(std::abs(corp_left_P.x - corp_right_P.x) < 50) continue;
//yyxx
out.locate[4*j+0] = max(0,corp_left_P.y);
out.locate[4*j+1] = min(height,corp_right_P.y);
out.locate[4*j+2] = max(0,corp_left_P.x);
out.locate[4*j+3] = min(width,corp_right_P.x);
}
//out_.begin() 是只想第一个元素的迭代器，确切的说，不是指针
//传的话就以 &*out_.begin() 来进行传递，实际上一下方式显得更简单，不那么晦涩
return 0;
}
python 部分代码:
if __name__ == '__main__':
#read the so
ll = cdll.LoadLibrary
lib_plate_locate = ll("./libpy_plate_locate.so")
#read image
frame = cv2.imread("/home/k/Longlongaaago/EasyPR-master/crop_vehicle/testImg/12166814_川BZT515.jpg")
frame_data = np.asarray(frame, dtype=np.int8)
#change the data form
frame_data = frame_data.ctypes.data_as(c_char_p)
#create the struct
rec = OutRec()
#reference the struct
state = lib_plate_locate.plate_recog(frame.shape[0], frame.shape[1], frame_data,byref(rec))
locate_list = []
if state !=0:
print("plate locate false! or none!")
for i in range(0,len(rec.locate),4):
if rec.locate[i+0] == rec.locate[i+1] == rec.locate[i+2] == rec.locate[i+3] ==0:
break;
targrt = {}
targrt["min_y"] = rec.locate[i+0]
targrt["max_y"] = rec.locate[i + 1]
targrt["min_x"] = rec.locate[i + 2]
targrt["max_x"] = rec.locate[i + 3]
print(rec.locate[i+0])
print(rec.locate[i + 1])
print(rec.locate[i + 2])
print(rec.locate[i + 3])
locate_list.append(targrt)
for i in range(len(locate_list)):
new_frame = frame[locate_list[i]["min_y"]:locate_list[i]["max_y"],locate_list[i]["min_x"]:locate_list[i]["max_x"],:]
cv2.imshow('image', new_frame)
cv2.waitKey()
至于如何进行编译,还是要自己学习一些编译知识
调用成功后,还要注意数值解析
