gocv PeopleDetection not working on Linux

PeopleDetection not working on Linux

Open Lallassu opened this issue 4 years ago • 4 comments

Description

I'm trying to run the HOGDefaultPeopleDetector() on Ubuntu 19.04 and it always detect a person in the center of the image for any image. So it seems to fail to detect correctly. Example output for running on webcam without anything in front (same result with image or avi file).

[(91,22)-(163,165)]
[(91,22)-(163,165)]
[(91,22)-(163,165)]
[(91,22)-(163,165)]
[(91,22)-(163,165)]
[(91,22)-(163,165)]
[(91,22)-(163,165)]
[(91,22)-(163,165)]
[(91,22)-(163,165)]

Steps to Reproduce

Source code for the example provided below. Note that I've tried without making the image gray and also tried different conversions AND without conversion. Same result each time.

package main

import (
	"fmt"
	"image"
	"image/color"
	"os"

	"gocv.io/x/gocv"
)

func main() {
	hog := gocv.NewHOGDescriptor()
	defer hog.Close()
	hog.SetSVMDetector(gocv.HOGDefaultPeopleDetector())

	deviceID := os.Args[1]
	webcam, err := gocv.OpenVideoCapture(deviceID)
	if err != nil {
		fmt.Printf("Error opening video capture device: %v\n", deviceID)
		return
	}
	defer webcam.Close()

	// color for the rect when faces detected
	blue := color.RGBA{0, 0, 255, 0}

	img := gocv.NewMat()
	defer img.Close()

	window := gocv.NewWindow("Detection")
	defer window.Close()

	for {
		if ok := webcam.Read(&img); !ok {
			fmt.Printf("Device closed: %v\n", deviceID)
			return
		}
		if img.Empty() {
			continue
		}

		gocv.Resize(img, &img, image.Point{}, 0.4, 0.4, 1)

		gocv.CvtColor(img, &img, gocv.ColorRGBToGray)
		gocv.Threshold(img, &img, 80, 255, gocv.ThresholdBinaryInv)

		rects := hog.DetectMultiScale(img)

		fmt.Printf("%v\n", rects)

		for _, r := range rects {
			gocv.Rectangle(&img, r, blue, 1)
		}
		window.IMShow(img)

		if window.WaitKey(1) >= 0 {
			break
		}
	}
}

Your Environment

Operating System and version: Ubuntu 19.04
OpenCV version used: 3.2.0
How did you install OpenCV? apt
GoCV version used: v0.22.0
Go version: 1.14.1
Did you run the env.sh or env.cmd script before trying to go run or go build? No