docs

cmd/examples/rest_example/main.go

@@ -0,0 +1,140 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"image"
+	_ "image/jpeg"
+	"io/ioutil"
+	"log"
+	"net/http"
+
+	"go-darknet"
+)
+
+var configFile = flag.String("configFile", "",
+	"Path to network layer configuration file. Example: cfg/yolov3.cfg")
+var weightsFile = flag.String("weightsFile", "",
+	"Path to weights file. Example: yolov3.weights")
+var serverPort = flag.Int("port", 8090,
+	"Listening port")
+
+func main() {
+	flag.Parse()
+
+	if *configFile == "" || *weightsFile == "" {
+		flag.Usage()
+		return
+	}
+
+	n := darknet.YOLONetwork{
+		GPUDeviceIndex:           0,
+		NetworkConfigurationFile: *configFile,
+		WeightsFile:              *weightsFile,
+		Threshold:                .25,
+	}
+	if err := n.Init(); err != nil {
+		log.Println(err)
+		return
+	}
+	defer n.Close()
+
+	http.HandleFunc("/detect_objects", detectObjects(&n))
+	http.ListenAndServe(fmt.Sprintf(":%d", *serverPort), nil)
+}
+
+// DarknetResp Response
+type DarknetResp struct {
+	NetTime     string              `json:"net_time"`
+	OverallTime string              `json:"overall_time"`
+	Detections  []*DarknetDetection `json:"detections"`
+}
+
+// DarknetDetection Information about single detection
+type DarknetDetection struct {
+	ClassID     int           `json:"class_id"`
+	ClassName   string        `json:"class_name"`
+	Probability float32       `json:"probability"`
+	StartPoint  *DarknetPoint `json:"start_point"`
+	EndPoint    *DarknetPoint `json:"end_point"`
+}
+
+// DarknetPoint image.Image point
+type DarknetPoint struct {
+	X int `json:"x"`
+	Y int `json:"y"`
+}
+
+func detectObjects(n *darknet.YOLONetwork) func(w http.ResponseWriter, req *http.Request) {
+	return func(w http.ResponseWriter, req *http.Request) {
+		// Restrict file size up to 10mb
+		req.ParseMultipartForm(10 << 20)
+
+		file, _, err := req.FormFile("image")
+		if err != nil {
+			fmt.Fprintf(w, fmt.Sprintf("Error reading FormFile: %s", err.Error()))
+			return
+		}
+		defer file.Close()
+
+		fileBytes, err := ioutil.ReadAll(file)
+		if err != nil {
+			fmt.Fprintf(w, fmt.Sprintf("Error reading bytes: %s", err.Error()))
+			return
+		}
+
+		imgSrc, _, err := image.Decode(bytes.NewReader(fileBytes))
+		if err != nil {
+			fmt.Fprintf(w, fmt.Sprintf("Error decoding bytes to image: %s", err.Error()))
+			return
+		}
+
+		imgDarknet, err := darknet.Image2Float32(imgSrc)
+		if err != nil {
+			fmt.Fprintf(w, fmt.Sprintf("Error converting image.Image to darknet.DarknetImage: %s", err.Error()))
+			return
+		}
+		defer imgDarknet.Close()
+
+		dr, err := n.Detect(imgDarknet)
+		if err != nil {
+			fmt.Fprintf(w, fmt.Sprintf("Error detecting objects: %s", err.Error()))
+			return
+		}
+
+		resp := DarknetResp{
+			NetTime:     fmt.Sprintf("%v", dr.NetworkOnlyTimeTaken),
+			OverallTime: fmt.Sprintf("%v", dr.OverallTimeTaken),
+			Detections:  []*DarknetDetection{},
+		}
+
+		for _, d := range dr.Detections {
+			for i := range d.ClassIDs {
+				bBox := d.BoundingBox
+				resp.Detections = append(resp.Detections, &DarknetDetection{
+					ClassID:     d.ClassIDs[i],
+					ClassName:   d.ClassNames[i],
+					Probability: d.Probabilities[i],
+					StartPoint: &DarknetPoint{
+						X: bBox.StartPoint.X,
+						Y: bBox.StartPoint.Y,
+					},
+					EndPoint: &DarknetPoint{
+						X: bBox.EndPoint.X,
+						Y: bBox.EndPoint.Y,
+					},
+				})
+			}
+		}
+
+		respBytes, err := json.Marshal(resp)
+		if err != nil {
+			fmt.Fprintf(w, fmt.Sprintf("Error encoding response: %s", err.Error()))
+			return
+		}
+
+		fmt.Fprintf(w, string(respBytes))
+	}
+}