diff --git a/go.mod b/go.mod
index f180b76..ae9347d 100644
--- a/go.mod
+++ b/go.mod
@@ -2,9 +2,4 @@ module github.com/pepabo/oyaki
 
 go 1.19
 
-require (
-	github.com/disintegration/imaging v1.6.2
-	github.com/h2non/bimg v1.1.9
-)
-
-require golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8 // indirect
+require github.com/h2non/bimg v1.1.9
diff --git a/go.sum b/go.sum
index 9d879fe..0133487 100644
--- a/go.sum
+++ b/go.sum
@@ -1,7 +1,2 @@
-github.com/disintegration/imaging v1.6.2 h1:w1LecBlG2Lnp8B3jk5zSuNqd7b4DXhcjwek1ei82L+c=
-github.com/disintegration/imaging v1.6.2/go.mod h1:44/5580QXChDfwIclfc/PCwrr44amcmDAg8hxG0Ewe4=
 github.com/h2non/bimg v1.1.9 h1:WH20Nxko9l/HFm4kZCA3Phbgu2cbHvYzxwxn9YROEGg=
 github.com/h2non/bimg v1.1.9/go.mod h1:R3+UiYwkK4rQl6KVFTOFJHitgLbZXBZNFh2cv3AEbp8=
-golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8 h1:hVwzHzIUGRjiF7EcUjqNxk3NCfkPxbDKRdnNE1Rpg0U=
-golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
diff --git a/webp_test.go b/webp_test.go
index d53f3e8..73e95d2 100644
--- a/webp_test.go
+++ b/webp_test.go
@@ -6,10 +6,7 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"os"
-	"os/exec"
 	"testing"
-
-	"github.com/disintegration/imaging"
 )
 
 func TestProxyWebP(t *testing.T) {
@@ -60,47 +57,6 @@ func TestConvJPG2WebP(t *testing.T) {
 
 }
 
-func BenchmarkConvJPG2WebP_OldCwebpMethod(b *testing.B) {
-	tmpF, err := os.CreateTemp("/tmp", "")
-	if err != nil {
-		b.Fatal("failed to create tmp file")
-	}
-	defer tmpF.Close()
-	defer os.Remove(tmpF.Name())
-
-	f, err := os.Open("./testdata/oyaki.jpg")
-	if err != nil {
-		b.Fatal("failed to open testdata")
-	}
-	defer f.Close()
-
-	// to re-use src bytes
-	src, err := io.ReadAll(f)
-	if err != nil {
-		b.Fatal("failed to open testdata")
-	}
-
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		b.StopTimer()
-		srcBuf := bytes.NewBuffer(src)
-		b.StartTimer()
-		img, err := imaging.Decode(srcBuf, imaging.AutoOrientation(true))
-		if err != nil {
-			b.Fail()
-		}
-
-		if err := imaging.Encode(tmpF, img, imaging.JPEG); err != nil {
-			b.Fail()
-		}
-
-		params := []string{"-quiet", "-mt", "-jpeg_like", f.Name(), "-o", "-"}
-		if _, err = exec.Command("cwebp", params...).Output(); err != nil {
-			b.Fail()
-		}
-	}
-}
-
 func BenchmarkConvJPG2WebP_bimg(b *testing.B) {
 	f, err := os.Open("./testdata/oyaki.jpg")
 	if err != nil {