QT C++调用python传递RGB图像和三维数组，并接受python返回值(图像)

目的：

用QT调用python代码，将QT读取的图像(Qimage)作为参数传入python中，将QT的三维数组作为参数传递给python，python接收QT传入的图像进行计算，将结果返回给QT并显示。

一 .pro 头文件的配置，和lib库的配置


INCLUDEPATH += \-I D:\tools\python3_9\include
INCLUDEPATH += \-I D:\tools\python3_9\Lib\site-packages\numpy\core\include
LIBS += \-L D:\tools\python3_9\libs -lpython39

二。系统环境变量的配置在path添加 python环境 D:/tools/python3_9

三，python环境的初始化

//加入python环境
1. Py_SetPythonHome(L"D:/tools/python3_9");

2. 类似于先连接上Python Py_Initialize();

3. 注意使用这个 import_array1(); 用于后边numpy数组的调用， import_array();会报无返回值的错误。

其他看代码注释


void  MainForm::init_python()
{//加入pythonPy_SetPythonHome(L"D:/tools/python3_9");// 1. 类似于先连接上PythonPy_Initialize();import_array1();if (!Py_IsInitialized()) {qDebug() << "Fail to init Python.";}// 2. 加入python文件的路径PyRun_SimpleString("import os");PyRun_SimpleString("import sys");std::string path = "sys.path.append('E:/DigitalScreen/StuEmo/realtime_detect')";PyRun_SimpleString(&path[0]);PyRun_SimpleString("print(sys.path)");// 3. 找到要用的python文件PyObject * pModule = PyImport_ImportModule("capture_xjh");if (pModule == NULL) {qDebug() <<"Fail to load Python module (capture_xjh.py)";}// 1. 找到Python的类PyObject* pDict = PyModule_GetDict(pModule);if(!pDict) {qDebug() << "Cant find dictionary.";}Py_DECREF(pModule);PyObject* pClassCalc = PyDict_GetItemString(pDict, "RtDetector");if (!pClassCalc) {qDebug() << "Cant find PythonClass class.";}Py_DECREF(pDict);// 2. 初始化对象PyObject* pConstruct = PyInstanceMethod_New(pClassCalc);if (!pConstruct) {qDebug() << "Cant find PythonClass constructor.";}Py_DECREF(pClassCalc);PyObject* cons_args = PyTuple_New(5);PyTuple_SetItem(cons_args, 0, Py_BuildValue("s",  "group1"));PyTuple_SetItem(cons_args, 1, Py_BuildValue("s",  "E:/DigitalScreen/StuEmo/GROUP_DATA/"));PyTuple_SetItem(cons_args, 2, Py_BuildValue("s",   "E:/DigitalScreen/StuEmo/weights/detr_face_body.pt"));PyTuple_SetItem(cons_args, 3, Py_BuildValue("s",   "E:/DigitalScreen/StuEmo/realtime_detect/Person_reID/model/ft_ResNet50/net_last.pth"));PyTuple_SetItem(cons_args, 4, Py_BuildValue("O",   Py_True));pInstance = PyObject_CallObject(pConstruct, cons_args);if (!pInstance) {qDebug() << "Cant construct instance.";}Py_DECREF(cons_args);Py_DECREF(pConstruct);// PyObject* methods = PyObject_Dir(pInstance);// if (methods) {//     // 遍历返回的方法列表//     for (Py_ssize_t i = 0; i < PyList_GET_SIZE(methods); ++i) {//         PyObject* method = PyList_GET_ITEM(methods, i);//         const char* methodName = PyUnicode_AsUTF8(method);//         qDebug() << "Method Name:" << methodName;//     }//     Py_DECREF(methods);// } else {//     qDebug() << "Failed to get methods of the instance.";// }//测试// PyObject* pRet =PyObject_CallMethod(pInstance,"addTest1","ii",5,6);// if (!pRet) {//     qDebug() << "Cant addTest.";// }// else{//     double ret = PyFloat_AsDouble(pRet);//     qDebug() << "sum: " << ret;// }// Py_DECREF(pRet);//通过图片检测QImage qImage ("E:/DigitalScreen/StuEmo/images/1.png");UsePythonface(  qImage);
}

四，Qimage 转换到numpy数组的使用

Qimage 传入的是QImage::Format_RGB888格式图片，通过

for (int i = 0; i < height; i++)
{
for (int j = 0; j < width; j++)
{
QRgb pixel = qImage.pixel( j,i);

CArrays[index++] = qRed(pixel);
CArrays[index++] = qGreen(pixel);
CArrays[index++] = qBlue(pixel);
}
}转换为一维数组CArrays

// 创建 NumPy 数组通过CArrays转换而来
npy_intp dims[3] = { height, width, 3 }; // 图像是RGB格式的
PyObject* imageArray = PyArray_SimpleNewFromData(3, dims, NPY_UINT8, (void*)CArrays);

返回值又通过 mempcpy(CArrays,PyArray_DATA(imageData),width*height*3);
再生成 QImage img((unsigned char*)CArrays, width, height, QImage::Format_RGB888);

调用 disp_image( img);显示图像


void MainForm::UsePythonface( QImage qImage)
{if(!qImage.isNull()){int width = qImage.width();int height = qImage.height();unsigned char *CArrays = (unsigned  char*)malloc(sizeof(unsigned char) * width*height*3);qDebug()<<"qImage.width()"<<qImage.width()<<"qImage.height()"<<qImage.height()<<"qImage.format()"<<qImage.format()<<endl;int index =0;for (int i = 0; i < height; i++){for (int j = 0; j < width; j++){QRgb pixel = qImage.pixel( j,i);CArrays[index++] = qRed(pixel);CArrays[index++] = qGreen(pixel);CArrays[index++] = qBlue(pixel);}}//qDebug()<< CArrays[width*height*3-1] <<endl;// 创建 NumPy 数组npy_intp dims[3] = { height, width, 3 }; // 假设图像是RGB格式的PyObject* imageArray = PyArray_SimpleNewFromData(3, dims, NPY_UINT8, (void*)CArrays);//qDebug()<<"start UsePythonface"<<endl;PyObject* imageData = PyObject_CallMethod(pInstance, "process_frame", "O", imageArray);Py_DECREF(imageArray);if(!imageData){PyErr_Print(); // 打印 Python 错误信息qDebug()<<"cant UsePythonface"<<endl;return;}// qDebug()<<"end UsePythonface"<<endl;mempcpy(CArrays,PyArray_DATA(imageData),width*height*3);QImage img((unsigned char*)CArrays, width, height,  QImage::Format_RGB888);//qDebug()<<"img.width()"<<img.width()<<"img.height()"<<img.height()<<"img.format()"<<img.format()<<endl;CArrays = nullptr;delete[] CArrays;Py_DECREF(imageData);disp_image( img);}
}