diff --git a/kadai1/.gitkeep b/kadai2/.gitkeep
similarity index 100%
rename from kadai1/.gitkeep
rename to kadai2/.gitkeep
diff --git a/kadai2/waytkheming/.gitignore b/kadai2/waytkheming/.gitignore
new file mode 100644
index 0000000..fa18208
--- /dev/null
+++ b/kadai2/waytkheming/.gitignore
@@ -0,0 +1,17 @@
+.DS_Store
+
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
diff --git a/kadai2/waytkheming/README.md b/kadai2/waytkheming/README.md
new file mode 100644
index 0000000..0d59e69
--- /dev/null
+++ b/kadai2/waytkheming/README.md
@@ -0,0 +1,16 @@
+# 課題１
+
+## 次の仕様を満たすコマンドを作って下さい
+
+- ディレクトリを指定する
+- 指定したディレクトリ以下のJPGファイルをPNGに変換（デフォルト）
+- ディレクトリ以下は再帰的に処理する
+- 変換前と変換後の画像形式を指定できる（オプション）
+
+## 以下を満たすように開発してください
+
+- mainパッケージと分離する
+- 自作パッケージと標準パッケージと準標準パッケージのみ使う
+- 準標準パッケージ：golang.org/x以下のパッケージ
+- ユーザ定義型を作ってみる
+- GoDocを生成してみる
diff --git a/kadai2/waytkheming/cli/cli.go b/kadai2/waytkheming/cli/cli.go
new file mode 100644
index 0000000..0231f18
--- /dev/null
+++ b/kadai2/waytkheming/cli/cli.go
@@ -0,0 +1,77 @@
+/*
+このパッケージはImageconvパッケージを起動するためのパッケージになります。
+
+*/
+
+package cli
+
+// Package cli is run Image convert function
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/waytkheming/godojo/dojo7/kadai2/waytkheming/imageconv"
+)
+
+var (
+	from, to string
+	wg       sync.WaitGroup
+)
+
+// Exit code.
+const (
+	ExitCodeOK = 0
+)
+
+// CLI -> cli struct
+type CLI struct {
+	outStream, errStream io.Writer
+}
+
+// NewCLI -> Initialize CLI
+func NewCLI(outStream, errStream io.Writer) *CLI {
+	return &CLI{outStream: outStream, errStream: errStream}
+}
+
+// Run -> run cli
+func (c *CLI) Run(args []string) int {
+	flags := flag.NewFlagSet("convert", flag.ContinueOnError)
+	flags.SetOutput(c.errStream)
+	flags.StringVar(&from, "from", "jpg",
+		"input file format (support: jpg/png/gif, default: jpg)")
+	flags.StringVar(&from, "f", "jpg",
+		"input file format (support: jpg/png/gif, default: jpg)")
+	flags.StringVar(&to, "to", "png",
+		"output file format (support: jpg/png/gif, default: png)")
+	flags.StringVar(&to, "t", "png",
+		"output file format (support: jpg/png/gif, default: png)")
+	flags.Parse(args[1:])
+	path := flags.Arg(0)
+
+	converter := imageconv.NewConverter(path, from, to)
+	fmt.Println(converter)
+	err := filepath.Walk(converter.Path, converter.CrawlFile)
+
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	queue := make(chan imageconv.ImageFile)
+	for _, image := range converter.Images {
+		wg.Add(1)
+		go converter.GetImages(queue, &wg)
+		queue <- image
+	}
+
+	close(queue)
+	wg.Wait()
+
+	return ExitCodeOK
+
+}
diff --git a/kadai2/waytkheming/cli/cli_test.go b/kadai2/waytkheming/cli/cli_test.go
new file mode 100644
index 0000000..2e501df
--- /dev/null
+++ b/kadai2/waytkheming/cli/cli_test.go
@@ -0,0 +1,24 @@
+package cli_test
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"github.com/waytkheming/godojo/dojo7/kadai2/waytkheming/cli"
+)
+
+func TestCLI_Run(t *testing.T) {
+	outStream, errStream := new(bytes.Buffer), new(bytes.Buffer)
+	c := cli.NewCLI(outStream, errStream)
+	args := strings.Split("convert ./../testdata/earthmap1k.jpg", " ")
+	exitCode := c.Run(args)
+
+	if exitCode != cli.ExitCodeOK {
+		t.Errorf("failed cli run, exit_code: %d", exitCode)
+	}
+
+	if errStream.Len() > 0 {
+		t.Errorf("failed cli run, output: %q", errStream.String())
+	}
+}
diff --git a/kadai2/waytkheming/imageconv/image.go b/kadai2/waytkheming/imageconv/image.go
new file mode 100644
index 0000000..c6bca47
--- /dev/null
+++ b/kadai2/waytkheming/imageconv/image.go
@@ -0,0 +1,22 @@
+package imageconv
+
+import (
+	"path/filepath"
+	"regexp"
+)
+
+//ImageFile -> Image struct
+type ImageFile struct {
+	Path   string
+	Name   string
+	Format string
+}
+
+// NewImage -> Initialize ImageFile
+func NewImage(path string) ImageFile {
+	format := filepath.Ext(path)
+	rep := regexp.MustCompile(format + "$")
+	name := filepath.Base(rep.ReplaceAllString(path, ""))
+
+	return ImageFile{Path: path, Name: name, Format: format}
+}
diff --git a/kadai2/waytkheming/imageconv/imageconv.go b/kadai2/waytkheming/imageconv/imageconv.go
new file mode 100644
index 0000000..5de9ff3
--- /dev/null
+++ b/kadai2/waytkheming/imageconv/imageconv.go
@@ -0,0 +1,124 @@
+/*
+このパッケージは、画像ファイルをpng,jpg,gifからpng,jpg,gifへ変換する機能を持っています。
+
+*/
+package imageconv
+
+import (
+	"image"
+	"image/gif"
+	"image/jpeg"
+	"image/png"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+)
+
+// Converter -> Converter struct
+type Converter struct {
+	Path   string
+	Images []ImageFile
+	From   string
+	To     string
+}
+
+// NewConverter -> Initialize ImageConverter
+func NewConverter(path string, from string, to string) Converter {
+	return Converter{Path: path, From: from, To: to}
+}
+
+// GetImages is queuing imageFile
+func (c *Converter) GetImages(q chan ImageFile, wg *sync.WaitGroup) {
+	for {
+		image, more := <-q
+		if more {
+			_ = c.Convert(image)
+		} else {
+			wg.Done()
+			return
+		}
+	}
+}
+
+//Convert -> Convert Image FIl
+func (c *Converter) Convert(i ImageFile) error {
+	file, err := os.Open(i.Path)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	image, err := c.decode(file)
+	if err != nil {
+		return err
+	}
+	outFile, err := os.Create(strings.TrimSuffix(c.Path, c.From) + c.To)
+	if err != nil {
+		return err
+	}
+	defer outFile.Close()
+
+	err = c.encode(outFile, image)
+
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// CrawlFile -> found image file and append Converter.Files
+func (c *Converter) CrawlFile(path string, info os.FileInfo, err error) error {
+	if checkExtension(filepath.Ext(path)) == ("." + c.From) {
+		if !info.IsDir() {
+			c.Images = append(c.Images, NewImage(path))
+		}
+	}
+	return nil
+}
+
+func checkExtension(path string) string {
+	if path == ".jpeg" {
+		return ".jpg"
+	}
+	return path
+}
+
+func (c *Converter) decode(file io.Reader) (image.Image, error) {
+	var (
+		img image.Image
+		err error
+	)
+	switch c.From {
+	case "jpeg", "jpg", "JPG", "JPEG":
+		img, err = jpeg.Decode(file)
+	case "gif", "GIF":
+		img, err = gif.Decode(file)
+	case "png", "PNG":
+		img, err = png.Decode(file)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	return img, nil
+}
+
+func (c *Converter) encode(file io.Writer, img image.Image) error {
+	var err error
+	switch c.To {
+	case "jpeg", "jpg", "JPG", "JPEG":
+		err = jpeg.Encode(file, img, nil)
+	case "gif", "GIF":
+		err = gif.Encode(file, img, nil)
+	case "png", "PNG":
+		err = png.Encode(file, img)
+	}
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
diff --git a/kadai2/waytkheming/imageconv/imageconv_test.go b/kadai2/waytkheming/imageconv/imageconv_test.go
new file mode 100644
index 0000000..8a57c3c
--- /dev/null
+++ b/kadai2/waytkheming/imageconv/imageconv_test.go
@@ -0,0 +1,119 @@
+package imageconv_test
+
+import (
+	"image/gif"
+	"image/jpeg"
+	"image/png"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/waytkheming/godojo/dojo7/kadai2/waytkheming/imageconv"
+)
+
+type testCase struct {
+	title  string
+	path   string
+	from   string
+	to     string
+	output string
+}
+
+func TestConvert(t *testing.T) {
+	var testFixtures = []testCase{
+		{
+			title:  "jpg to png",
+			path:   "../testdata/earthmap1k.jpg",
+			from:   "jpg",
+			to:     "png",
+			output: "../testdata/earthmap1k.png",
+		},
+		{
+			title:  "png to jpg",
+			path:   "../testdata/earthmap1k.png",
+			from:   "png",
+			to:     "jpg",
+			output: "../testdata/earthmap1k.jpg",
+		},
+		{
+			title:  "jpg to gif",
+			path:   "../testdata/earthmap1k.jpg",
+			from:   "jpg",
+			to:     "gif",
+			output: "../testdata/earthmap1k.gif",
+		},
+		{
+			title:  "png to gif",
+			path:   "../testdata/earthmap1k.png",
+			from:   "png",
+			to:     "gif",
+			output: "../testdata/earthmap1k.gif",
+		},
+		{
+			title:  "gif to jpg",
+			path:   "../testdata/earthmap1k.gif",
+			from:   "gif",
+			to:     "jpg",
+			output: "../testdata/earthmap1k.jpg",
+		},
+		{
+			title:  "gif to png",
+			path:   "../testdata/earthmap1k.gif",
+			from:   "gif",
+			to:     "png",
+			output: "../testdata/earthmap1k.png",
+		},
+	}
+	for _, testFixture := range testFixtures {
+		c := imageconv.NewConverter(testFixture.path, testFixture.from, testFixture.to)
+		i := imageconv.NewImage(testFixture.path)
+		t.Run("Check walk", func(t *testing.T) {
+			checkWalk(t, c)
+		})
+		t.Run("Check convert", func(t *testing.T) {
+			checkConvert(t, c, i)
+		})
+		t.Run("Check format", func(t *testing.T) {
+			checkFormat(t, testFixture.output, testFixture.to)
+		})
+	}
+}
+
+func checkWalk(t *testing.T, c imageconv.Converter) {
+	t.Helper()
+	if err := filepath.Walk(c.Path, c.CrawlFile); err != nil {
+		t.Errorf("Error: %s", err)
+	}
+}
+
+func checkConvert(t *testing.T, c imageconv.Converter, i imageconv.ImageFile) {
+	t.Helper()
+	if err := c.Convert(i); err != nil {
+		t.Errorf("Error: %s", err)
+	}
+}
+
+func checkFormat(t *testing.T, path string, to string) {
+	t.Helper()
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		t.Errorf("Expected output file %s %s is not exist", path, err.Error())
+	}
+	file, err := os.Open(path)
+	if err != nil {
+		t.Errorf("Couldn't open file path: %s, fileType: %s, error: %v", path, to, err)
+	}
+	defer file.Close()
+
+	switch to {
+	case "jpg", "jpeg":
+		_, err = jpeg.Decode(file)
+	case "png":
+		_, err = png.Decode(file)
+	case "gif":
+		_, err = gif.Decode(file)
+	}
+
+	if err != nil {
+		t.Errorf("Couldn't decode path: %s, fileType: %s, error: %v", path, to, err)
+	}
+}
diff --git a/kadai2/waytkheming/main.go b/kadai2/waytkheming/main.go
new file mode 100644
index 0000000..4002934
--- /dev/null
+++ b/kadai2/waytkheming/main.go
@@ -0,0 +1,14 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/waytkheming/godojo/dojo7/kadai2/waytkheming/cli"
+)
+
+func main() {
+	fmt.Println("Start running CLI...")
+	cli := cli.NewCLI(os.Stdout, os.Stderr)
+	os.Exit(cli.Run(os.Args))
+}
diff --git a/kadai2/waytkheming/screenshots/godoc-cli-pkg.png b/kadai2/waytkheming/screenshots/godoc-cli-pkg.png
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diff --git a/kadai2/waytkheming/screenshots/godoc-imageconv-pkg.png b/kadai2/waytkheming/screenshots/godoc-imageconv-pkg.png
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diff --git a/kadai2/waytkheming/testdata/earthmap1k.gif b/kadai2/waytkheming/testdata/earthmap1k.gif
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diff --git a/kadai2/waytkheming/testdata/earthmap1k.jpg b/kadai2/waytkheming/testdata/earthmap1k.jpg
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diff --git a/kadai2/waytkheming/testdata/earthmap1k.png b/kadai2/waytkheming/testdata/earthmap1k.png
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