[OpenCV] Chapter01-05 Working with UI elements such as scrollbars in OpenCV window

Working with UI elements such as scrollbars in OpenCV window

Source Code

package main

import (
 "log"

 "gocv.io/x/gocv"
)

func main() {
 windowForTrackbar := gocv.NewWindow("Trackbar Window")
 defer windowForTrackbar.Close()

 trackbarR := windowForTrackbar.CreateTrackbar("R", 255)
 trackbarG := windowForTrackbar.CreateTrackbar("G", 255)
 trackbarB := windowForTrackbar.CreateTrackbar("B", 255)
 trackbarA := windowForTrackbar.CreateTrackbar("A", 10)

 mat := gocv.NewMatWithSize(300, 300, gocv.MatTypeCV8UC3)

 log.Println("-----------------------")
 log.Println("Rows:", mat.Rows())
 log.Println("Cols:", mat.Cols())

 for {
  // BGR
  blue := float64(trackbarB.GetPos())
  green := float64(trackbarG.GetPos())
  red := float64(trackbarR.GetPos())
  alpha := float64(trackbarA.GetPos()) / 10

  log.Println("-----------------------")
  log.Println("blue:", blue)
  log.Println("green:", green)
  log.Println("red:", red)
  log.Println("alpha:", alpha)

  mat.SetTo(gocv.NewScalar(blue, green, red, alpha))

  windowForTrackbar.IMShow(mat)

  key := windowForTrackbar.WaitKey(3)
  if key == 27 {
   break
  }
 }
}

Execute Result