diff --git a/coolq/bot.go b/coolq/bot.go
index 126de63..de84131 100644
--- a/coolq/bot.go
+++ b/coolq/bot.go
@@ -23,6 +23,7 @@ import (
 	"github.com/Mrs4s/go-cqhttp/db"
 	"github.com/Mrs4s/go-cqhttp/global"
 	"github.com/Mrs4s/go-cqhttp/internal/base"
+	"github.com/Mrs4s/go-cqhttp/internal/mime"
 )
 
 // CQBot CQBot结构体,存储Bot实例相关配置
@@ -152,10 +153,9 @@ func (bot *CQBot) uploadLocalImage(target message.Source, img *LocalImageElement
 		defer func() { _ = f.Close() }()
 		img.Stream = f
 	}
-	if lawful, mime := base.IsLawfulImage(img.Stream); !lawful {
-		return nil, errors.New("image type error: " + mime)
+	if mt, ok := mime.CheckImage(img.Stream); !ok {
+		return nil, errors.New("image type error: " + mt)
 	}
-	// todo: enable multi-thread upload, now got error code 81
 	i, err := bot.Client.UploadImage(target, img.Stream, 4)
 	if err != nil {
 		return nil, err
diff --git a/coolq/cqcode.go b/coolq/cqcode.go
index 283213b..2c3bc65 100644
--- a/coolq/cqcode.go
+++ b/coolq/cqcode.go
@@ -28,6 +28,7 @@ import (
 	"github.com/Mrs4s/go-cqhttp/global"
 	"github.com/Mrs4s/go-cqhttp/internal/base"
 	"github.com/Mrs4s/go-cqhttp/internal/cache"
+	"github.com/Mrs4s/go-cqhttp/internal/mime"
 	"github.com/Mrs4s/go-cqhttp/internal/param"
 )
 
@@ -844,8 +845,8 @@ func (bot *CQBot) ToElement(t string, d map[string]string, sourceType message.So
 			return nil, err
 		}
 		if !global.IsAMRorSILK(data) {
-			lawful, mt := base.IsLawfulAudio(bytes.NewReader(data))
-			if !lawful {
+			mt, ok := mime.CheckAudio(bytes.NewReader(data))
+			if !ok {
 				return nil, errors.New("audio type error: " + mt)
 			}
 			data, err = global.EncoderSilk(data)
diff --git a/internal/base/feature.go b/internal/base/feature.go
index f27c0a0..d57a9aa 100644
--- a/internal/base/feature.go
+++ b/internal/base/feature.go
@@ -1,8 +1,6 @@
 package base
 
 import (
-	"io"
-
 	"github.com/pkg/errors"
 )
 
@@ -19,13 +17,3 @@ func encodeSilk(_ []byte, _ string) ([]byte, error) {
 func resampleSilk(data []byte) []byte {
 	return data
 }
-
-// Mime scan feature
-var (
-	IsLawfulImage = nocheck // 检查图片MIME
-	IsLawfulAudio = nocheck // 检查音频MIME
-)
-
-func nocheck(_ io.ReadSeeker) (bool, string) {
-	return true, ""
-}
diff --git a/modules/mime/mime.go b/internal/mime/mime.go
similarity index 65%
rename from modules/mime/mime.go
rename to internal/mime/mime.go
index f6bfa4b..c8765bd 100644
--- a/modules/mime/mime.go
+++ b/internal/mime/mime.go
@@ -9,11 +9,6 @@ import (
 	"github.com/Mrs4s/go-cqhttp/internal/base"
 )
 
-func init() {
-	base.IsLawfulImage = checkImage
-	base.IsLawfulAudio = checkAudio
-}
-
 const limit = 4 * 1024
 
 func scan(r io.ReadSeeker) string {
@@ -24,15 +19,15 @@ func scan(r io.ReadSeeker) string {
 	return http.DetectContentType(in)
 }
 
-// checkImage 判断给定流是否为合法图片
+// CheckImage 判断给定流是否为合法图片
 // 返回 是否合法, 实际Mime
 // 判断后会自动将 Stream Seek 至 0
-func checkImage(r io.ReadSeeker) (ok bool, t string) {
+func CheckImage(r io.ReadSeeker) (t string, ok bool) {
 	if base.SkipMimeScan {
-		return true, ""
+		return "", true
 	}
 	if r == nil {
-		return false, "image/nil-stream"
+		return "image/nil-stream", false
 	}
 	t = scan(r)
 	switch t {
@@ -42,15 +37,15 @@ func checkImage(r io.ReadSeeker) (ok bool, t string) {
 	return
 }
 
-// checkImage 判断给定流是否为合法音频
-func checkAudio(r io.ReadSeeker) (bool, string) {
+// CheckAudio 判断给定流是否为合法音频
+func CheckAudio(r io.ReadSeeker) (string, bool) {
 	if base.SkipMimeScan {
-		return true, ""
+		return "", true
 	}
 	t := scan(r)
 	// std mime type detection is not full supported for audio
 	if strings.Contains(t, "text") || strings.Contains(t, "image") {
-		return false, t
+		return t, false
 	}
-	return true, t
+	return t, true
 }
diff --git a/main.go b/main.go
index fa75ded..1d79704 100644
--- a/main.go
+++ b/main.go
@@ -5,7 +5,6 @@ import (
 	"github.com/Mrs4s/go-cqhttp/cmd/gocq"
 
 	_ "github.com/Mrs4s/go-cqhttp/db/leveldb"   // leveldb
-	_ "github.com/Mrs4s/go-cqhttp/modules/mime" // mime检查模块
 	_ "github.com/Mrs4s/go-cqhttp/modules/silk" // silk编码模块
 	// 其他模块
 	// _ "github.com/Mrs4s/go-cqhttp/db/mongodb"    // mongodb 数据库支持