[OpenCV] Chapter02-03 Non-image data persistence

Read image from file

Source Code

package main

import (
 "gocv.io/x/gocv"
 "io/ioutil"
 "log"
 "math/rand"
)

const (
 WIDTH   = 300
 HEIGHT  = 300
 CHANNEL = 3
)

func main() {
 filePath := "./random.cvs"

 newImage := createRandomImage(WIDTH, HEIGHT, CHANNEL)

 // save file
 err := ioutil.WriteFile(filePath, newImage, 0644)
 if err != nil {
  log.Panic("Can not write file", err)
  return
 }

 loadImage, err := ioutil.ReadFile(filePath)
 if err != nil {
  log.Panic("Can not read file", err)
  return
 }

 // show image
 mat, err := gocv.NewMatFromBytes(WIDTH, HEIGHT, gocv.MatTypeCV8UC3, loadImage)
 if err != nil {
  log.Panic("Can not convert bytes to Mat", err)
  return
 }

 window := gocv.NewWindow("Random Image")
 defer window.Close()
 window.IMShow(mat)

 // wait
 for {
  key := gocv.WaitKey(3)
  if key == 27 {
   log.Println("Pressed ESC")
   break
  }
 }
}

func createRandomImage(rows, cols, channel int) []uint8 {
 image := make([]uint8, rows*cols*channel)
 for row := 0; row < rows; row++ {
  for col := 0; col < cols; col++ {
   for ch := 0; ch < channel; ch++ {
    index := (rows*row+col)*channel + ch
    image[index] = uint8(rand.Intn(255))
   }
  }
 }
 return image
}

Execute Result