package imageutils import ( "fmt" "image/png" "os" "path/filepath" "testing" ) // Returns path of first occured file // with png extension in user's home directory. func firstPNG(root string) (filename string, err error) { var fn filepath.WalkFunc = func(path string, info os.FileInfo, fileErr error) error { if fileErr != nil { return fileErr } if !info.IsDir() && filepath.Ext(path) == ".png" { filename = path return nil } return nil } err = filepath.Walk(root, fn) return } func TestColorToHex(t *testing.T) { root := os.Getenv("HOME") path, err := firstPNG(root) if err != nil { t.Fatal(err) } f, err := os.Open(path) if err != nil { t.Fatal(err) } img, err := png.Decode(f) if err != nil { t.Fatal(err) } fmt.Println(ColorToHex(img.At(0, 0))) }