diff --git a/go.mod b/go.mod
index af97d99..5b7f30b 100644
--- a/go.mod
+++ b/go.mod
@@ -11,5 +11,6 @@ require (
 require (
 	github.com/gorilla/websocket v1.4.2 // indirect
 	golang.org/x/crypto v0.1.0 // indirect
+	golang.org/x/image v0.14.0 // indirect
 	golang.org/x/sys v0.1.0 // indirect
 )
diff --git a/go.sum b/go.sum
index d175853..a384f07 100644
--- a/go.sum
+++ b/go.sum
@@ -7,6 +7,8 @@ github.com/robfig/cron/v3 v3.0.1/go.mod h1:eQICP3HwyT7UooqI/z+Ov+PtYAWygg1TEWWzG
 golang.org/x/crypto v0.0.0-20210421170649-83a5a9bb288b/go.mod h1:T9bdIzuCu7OtxOm1hfPfRQxPLYneinmdGuTeoZ9dtd4=
 golang.org/x/crypto v0.1.0 h1:MDRAIl0xIo9Io2xV565hzXHw3zVseKrJKodhohM5CjU=
 golang.org/x/crypto v0.1.0/go.mod h1:RecgLatLF4+eUMCP1PoPZQb+cVrJcOPbHkTkbkB9sbw=
+golang.org/x/image v0.14.0 h1:tNgSxAFe3jC4uYqvZdTr84SZoM1KfwdC9SKIFrLjFn4=
+golang.org/x/image v0.14.0/go.mod h1:HUYqC05R2ZcZ3ejNQsIHQDQiwWM4JBqmm6MKANTp4LE=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.1.0 h1:kunALQeHf1/185U1i0GOB/fy1IPRDDpuoOOqRReG57U=
diff --git a/lib/cmds/chat.go b/lib/cmds/chat.go
index 23fcc3d..5bc8e35 100644
--- a/lib/cmds/chat.go
+++ b/lib/cmds/chat.go
@@ -16,6 +16,8 @@ import (
 	"time"
 	"unicode/utf8"
 
+	_ "golang.org/x/image/webp"
+
 	"github.com/bwmarrin/discordgo"
 	"github.com/tpc3/Bocchi-Go/lib/chat"
 	"github.com/tpc3/Bocchi-Go/lib/config"
@@ -95,11 +97,6 @@ func ChatCmd(session *discordgo.Session, orgMsg *discordgo.MessageCreate, guild
 			return
 		}
 
-		if !strings.Contains(imgurl, ".png") && !strings.Contains(imgurl, ".jpg") && !strings.Contains(imgurl, ".jpeg") && !strings.Contains(imgurl, ".gif") && !strings.Contains(imgurl, ".webp") {
-			ErrorReply(session, orgMsg, config.Lang[config.CurrentConfig.Guild.Lang].Error.NoSupportimage)
-			return
-		}
-
 		resp, err := http.Get(imgurl)
 		if err != nil {
 			if strings.Contains(err.Error(), "no such host") {
@@ -113,6 +110,21 @@ func ChatCmd(session *discordgo.Session, orgMsg *discordgo.MessageCreate, guild
 			ErrorReply(session, orgMsg, config.Lang[config.CurrentConfig.Guild.Lang].Error.BrokenLink)
 			return
 		}
+		imageConfig, imageType, err := image.DecodeConfig(resp.Body)
+		if err != nil {
+			if strings.Contains(err.Error(), "unknown format") {
+				ErrorReply(session, orgMsg, config.Lang[config.CurrentConfig.Guild.Lang].Error.NoSupportimage)
+				return
+			}
+			log.Panic("Faild to decode: ", err)
+		}
+
+		if imageType != "png" && imageType != "jpeg" && imageType != "webp" && imageType != "gif" {
+			ErrorReply(session, orgMsg, config.Lang[config.CurrentConfig.Guild.Lang].Error.NoSupportimage)
+			return
+		}
+
+		log.Print(imageType)
 
 		model = "gpt-4-vision-preview"
 
@@ -142,10 +154,6 @@ func ChatCmd(session *discordgo.Session, orgMsg *discordgo.MessageCreate, guild
 		if detail == "low" {
 			detcost = 85
 		} else if detail == "high" {
-			imageConfig, _, err := image.DecodeConfig(resp.Body)
-			if err != nil {
-				log.Panic("Faild to decode: ", err)
-			}
 
 			width := imageConfig.Width
 			height := imageConfig.Height
diff --git a/lib/config/lang.go b/lib/config/lang.go
index 3dba580..1d6f6ff 100644
--- a/lib/config/lang.go
+++ b/lib/config/lang.go
@@ -147,7 +147,7 @@ func loadLang() {
 			LongResponse:        "AIの生成した文章が長すぎました。指示を変更してもう一度お試しください。",
 			TimeOut:             "要求がタイムアウトしました。もう一度お試しください。",
 			CantReply:           "エラーへの返信はできません。",
-			NoDetail:            "highかlowのみ選択できます。",
+			NoDetail:            "`-d`の値はhighかlowのみです。。",
 			NoImage:             "画像が入力されていません。",
 			NoSupportimage:      "その画像形式は対応していません。",
 			NoUrl:               "URLを入力してください。",