main.go

// What it does:
//
// This example uses the VideoCapture class to capture frames from a connected webcam,
// and displays the video in a Window class.
//
// How to run:
//
// 		go run ./cmd/capwindow/main.go
//

package main

import (
	"fmt"
	"os"

	"gocv.io/x/gocv"
)

func main() {
	if len(os.Args) < 2 {
		fmt.Println("How to run:\n\tcapwindow [camera ID]")
		return
	}

	// parse args
	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()

	window := gocv.NewWindow("Capture Window")
	defer window.Close()

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

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

		window.IMShow(img)
		if window.WaitKey(1) == 27 {
			break
		}
	}
}