使c ++插件asynchronous
我已经设法将dlibvideo跟踪器集成到我的节点应用程序中。 我现在的问题是让它不被阻塞。 任何帮助将不胜感激。 谢谢。
这是我的代码
#ifndef MYOBJECT_H #define MYOBJECT_H #include "ImageDetails.h" #include "opencv2/core/core_c.h" #include "../dlib/opencv/cv_image.h" #include "../dlib/image_processing.h" #include "../dlib/gui_widgets.h" #include "../dlib/image_io.h" #include "../dlib/dir_nav.h" #include "/home/pi/projects/lib/node-opencv-master/src/Matrix.h" #include "/home/pi/projects/lib/node-opencv-master/src/Contours.h" #include <nan.h> //#include <node_object_wrap.h> using namespace dlib; using namespace cv; using namespace std; class MyObject : public Nan::ObjectWrap { public: static void Init(v8::Local<v8::Object> exports); private: explicit MyObject(std::vector<ImageDetails> details, cv::Mat img); ~MyObject(); static void New(const Nan::FunctionCallbackInfo<v8::Value>& args); static void UpdateImage(const Nan::FunctionCallbackInfo<v8::Value>& args); static Nan::Persistent<v8::Function> constructor; std::vector <correlation_tracker> value_; }; #endif Imagedetails.h
#ifndef IMAGEDETAILS_H #define IMAGEDETAILS_H class ImageDetails { public: int width; int height; int xpoint; int ypoint; }; #endif
//
#include "VideoTracking.h" Nan::Persistent<v8::Function> MyObject::constructor; ImageDetails unpack_details(Isolate * , const Handle<Object> sample_obj); MyObject::MyObject(std::vector<ImageDetails> details, cv::Mat img){ value_.resize(details.size()); dlib::array2d<bgr_pixel> dlibImage; dlib::assign_image(dlibImage, dlib::cv_image<bgr_pixel>(img)); //value_.start_track(dlibImage, centered_rect(point(93,110), 38, 86)); for (unsigned int i=0; i < details.size(); i++){ cout << details[i].xpoint << endl; cout << details[i].ypoint << endl; cout << details[i].width << endl; cout << details[i].height << endl; value_[i].start_track(dlibImage, centered_rect(point(details[i].xpoint, details[i].ypoint), details[i].width, details[i].height)); } } MyObject::~MyObject() { } void MyObject::Init(v8::Local<v8::Object> exports) { Nan::HandleScope scope; // Prepare constructor template v8::Local<v8::FunctionTemplate> tpl = Nan::New<v8::FunctionTemplate>(New); tpl->SetClassName(Nan::New("MyObject").ToLocalChecked()); tpl->InstanceTemplate()->SetInternalFieldCount(1); Nan::SetPrototypeMethod(tpl, "updateImage", UpdateImage); constructor.Reset(tpl->GetFunction()); exports->Set(Nan::New("MyObject").ToLocalChecked(), tpl->GetFunction()); } void MyObject::New(const Nan::FunctionCallbackInfo<v8::Value>& args) { Isolate* isolate = args.GetIsolate(); v8::Local<v8::Object> location_obj = args[1]->ToObject(); v8::Handle<v8::Value> img_Value = location_obj->Get(v8::String::NewFromUtf8(isolate,"img")); v8::Local<v8::Array> input = v8::Local<v8::Array>::Cast(args[0]); unsigned int num_locations = input->Length(); std::vector<ImageDetails> tmp; // tmp.resize(num_locations); for (unsigned int i = 0; i < num_locations; i++) { tmp.push_back(unpack_details(isolate, v8::Local<v8::Object>::Cast(input->Get(i)))); } MyObject* obj = new MyObject(tmp, Nan::ObjectWrap::Unwrap<node_opencv::Matrix>(img_Value->ToObject())->mat); obj->Wrap(args.This()); args.GetReturnValue().Set(args.This()); } ImageDetails unpack_details(Isolate * isolate, const v8::Handle<v8::Object> location_obj) { ImageDetails tmp; v8::Handle<v8::Value> width = location_obj->Get(v8::String::NewFromUtf8(isolate,"width")); v8::Handle<v8::Value> heigth = location_obj->Get(v8::String::NewFromUtf8(isolate,"heigth")); v8::Handle<v8::Value> xpoint = location_obj->Get(v8::String::NewFromUtf8(isolate,"xpoint")); v8::Handle<v8::Value> ypoint = location_obj->Get(v8::String::NewFromUtf8(isolate,"ypoint")); tmp.width = width->NumberValue(); tmp.height = heigth->NumberValue(); tmp.xpoint = xpoint->NumberValue(); tmp.ypoint = ypoint->NumberValue(); return tmp; } void MyObject::UpdateImage(const Nan::FunctionCallbackInfo<v8::Value>& args) { // image_window win; Isolate* isolate = args.GetIsolate(); v8::Local<v8::Object> location_obj = args[0]->ToObject(); v8::Handle<v8::Value> img_Value = location_obj->Get(v8::String::NewFromUtf8(isolate,"img")); dlib::array2d<bgr_pixel> dlibImage; dlib::assign_image(dlibImage, dlib::cv_image<bgr_pixel>(Nan::ObjectWrap::Unwrap<node_opencv::Matrix>(img_Value->ToObject())->mat)); MyObject* obj = ObjectWrap::Unwrap<MyObject>(args.Holder()); v8::Local<v8::Array> arr = Array::New(isolate); for (unsigned int i=0; i < obj->value_.size(); i++){ obj->value_[i].update(dlibImage); cv::Rect r = cv::Rect(obj->value_[i].get_position().left(), obj->value_[i].get_position().top(), obj->value_[i].get_position().width(), obj->value_[i].get_position().height()); v8::Local < v8::Object > x = Nan::New<v8::Object>(); x->Set(Nan::New("x").ToLocalChecked(), Nan::New < Number > (rx)); x->Set(Nan::New("y").ToLocalChecked(), Nan::New < Number > (ry)); x->Set(Nan::New("width").ToLocalChecked(), Nan::New < Number > (r.width)); x->Set(Nan::New("height").ToLocalChecked(), Nan::New < Number > (r.height)); arr->Set(i, x); } // obj->value_.update(dlibImage); // // win.set_image(dlibImage); // win.clear_overlay(); // win.add_overlay(obj->value_.get_position()); //// sleep(10000); // cout << obj->value_.get_position().top() <<endl; // cin.get(); // Handle<Value> argv1[] = { Null(isolate) , arr}; args.GetReturnValue().Set(arr); }
基本上我需要一种方法来创build跟踪器，并稍后进行更新。 因此，我决定在创build一个新对象时创build跟踪器，并且在什么之后进行更新。 目前这是如何在我的js文件中调用。
这是我创build它的方式
var loc = { xpoint: detobj.x, ypoint: detobj.y, heigth: detobj.height, width: detobj.width }; details.push(loc); var image_obj = new addon.MyObject(details, obj1);
这是我如何更新图像
var obj = {img:matrix} var detobjs = image_obj.updateImage(obj1); for(var i =0; i < detobjs.length; i++){ var detobj = detobjs[i]; matrix.rectangle([detobj.x, detobj.y], [detobj.width, detobj.height], COLORRED, 1); } procobj.frame.imagejpg = matrix.toBuffer();
谢谢。
有很多教程描述如何做到这一点。 例如使用Nan构buildNode.js的asynchronousC ++插件 。
有两种常见的方法：
- 你挂钩到
libuv事件循环，然后在任务完成后调用JavaScript完成callback。 这种方法通常在nodejs中使用。 - 你使用自己的线程/任务。 这种方式JavaScript代码负责查询结果。 这种方法更容易实现，特别是如果你的插件已经使用了一些线程/任务，但需要额外的JavaScript代码来处理。