diff --git a/imageimpl.go b/imageimpl.go
index 152895f4c..92c19df12 100644
--- a/imageimpl.go
+++ b/imageimpl.go
@@ -28,26 +28,16 @@ import (
 	"github.com/hajimehoshi/ebiten/internal/loop"
 )
 
-type drawImageHistoryItem struct {
-	image    *Image
-	vertices []int16
-	geom     GeoM
-	colorm   ColorM
-	mode     opengl.CompositeMode
-}
-
 type imageImpl struct {
-	image            *graphics.Image
-	disposed         bool
-	width            int
-	height           int
-	filter           Filter
-	pixels           []uint8
-	baseColor        color.Color
-	drawImageHistory []*drawImageHistoryItem
-	volatile         bool
-	screen           bool
-	m                sync.Mutex
+	image         *graphics.Image
+	disposed      bool
+	width         int
+	height        int
+	filter        Filter
+	restoringInfo imageRestoringInfo
+	volatile      bool
+	screen        bool
+	m             sync.Mutex
 }
 
 func newImageImpl(width, height int, filter Filter, volatile bool) (*imageImpl, error) {
@@ -61,8 +51,9 @@ func newImageImpl(width, height int, filter Filter, volatile bool) (*imageImpl,
 		height:   height,
 		filter:   filter,
 		volatile: volatile,
-		pixels:   make([]uint8, width*height*4),
 	}
+	i.restoringInfo.imageImpl = i
+	i.restoringInfo.resetWithPixels(make([]uint8, width*height*4))
 	runtime.SetFinalizer(i, (*imageImpl).Dispose)
 	return i, nil
 }
@@ -93,8 +84,9 @@ func newImageImplFromImage(source image.Image, filter Filter) (*imageImpl, error
 		width:  w,
 		height: h,
 		filter: filter,
-		pixels: pixels,
 	}
+	i.restoringInfo.imageImpl = i
+	i.restoringInfo.resetWithPixels(pixels)
 	runtime.SetFinalizer(i, (*imageImpl).Dispose)
 	return i, nil
 }
@@ -110,8 +102,9 @@ func newScreenImageImpl(width, height int) (*imageImpl, error) {
 		height:   height,
 		volatile: true,
 		screen:   true,
-		pixels:   make([]uint8, width*height*4),
 	}
+	i.restoringInfo.imageImpl = i
+	i.restoringInfo.resetWithPixels(make([]uint8, width*height*4))
 	runtime.SetFinalizer(i, (*imageImpl).Dispose)
 	return i, nil
 }
@@ -122,9 +115,7 @@ func (i *imageImpl) Fill(clr color.Color) error {
 	if i.disposed {
 		return errors.New("ebiten: image is already disposed")
 	}
-	i.pixels = nil
-	i.baseColor = clr
-	i.drawImageHistory = nil
+	i.restoringInfo.fill(clr)
 	return i.image.Fill(clr)
 }
 
@@ -137,9 +128,7 @@ func (i *imageImpl) clearIfVolatile() error {
 	if !i.volatile {
 		return nil
 	}
-	i.pixels = nil
-	i.baseColor = nil
-	i.drawImageHistory = nil
+	i.restoringInfo.clear()
 	return i.image.Fill(color.Transparent)
 }
 
@@ -181,7 +170,7 @@ func (i *imageImpl) DrawImage(image *Image, options *DrawImageOptions) error {
 		colorm:   options.ColorM,
 		mode:     opengl.CompositeMode(options.CompositeMode),
 	}
-	i.drawImageHistory = append(i.drawImageHistory, c)
+	i.restoringInfo.appendDrawImageHistory(c)
 	geom := &options.GeoM
 	colorm := &options.ColorM
 	mode := opengl.CompositeMode(options.CompositeMode)
@@ -200,26 +189,11 @@ func (i *imageImpl) At(x, y int, context *opengl.Context) color.Color {
 	if i.disposed {
 		return color.Transparent
 	}
-	if i.pixels == nil || i.drawImageHistory != nil {
-		var err error
-		i.pixels, err = i.image.Pixels(context)
-		if err != nil {
-			panic(err)
-		}
-		i.drawImageHistory = nil
+	clr, err := i.restoringInfo.at(x, y, context)
+	if err != nil {
+		panic(err)
 	}
-	idx := 4*x + 4*y*i.width
-	r, g, b, a := i.pixels[idx], i.pixels[idx+1], i.pixels[idx+2], i.pixels[idx+3]
-	return color.RGBA{r, g, b, a}
-}
-
-func (i *imageImpl) hasHistoryWith(target *Image) bool {
-	for _, c := range i.drawImageHistory {
-		if c.image == target {
-			return true
-		}
-	}
-	return false
+	return clr
 }
 
 func (i *imageImpl) resetHistoryIfNeeded(target *Image, context *opengl.Context) error {
@@ -228,26 +202,16 @@ func (i *imageImpl) resetHistoryIfNeeded(target *Image, context *opengl.Context)
 	if i.disposed {
 		return nil
 	}
-	if i.drawImageHistory == nil {
-		return nil
+	if err := i.restoringInfo.resetHistoryIfNeeded(target, context); err != nil {
+		return err
 	}
-	if !i.hasHistoryWith(target) {
-		return nil
-	}
-	var err error
-	i.pixels, err = i.image.Pixels(context)
-	if err != nil {
-		return nil
-	}
-	i.baseColor = nil
-	i.drawImageHistory = nil
 	return nil
 }
 
 func (i *imageImpl) hasHistory() bool {
 	i.m.Lock()
 	defer i.m.Unlock()
-	return i.drawImageHistory != nil
+	return i.restoringInfo.hasHistory()
 }
 
 func (i *imageImpl) restore(context *opengl.Context) error {
@@ -274,42 +238,11 @@ func (i *imageImpl) restore(context *opengl.Context) error {
 		}
 		return nil
 	}
-	img := image.NewRGBA(image.Rect(0, 0, i.width, i.height))
-	if i.pixels != nil {
-		for j := 0; j < i.height; j++ {
-			copy(img.Pix[j*img.Stride:], i.pixels[j*i.width*4:(j+1)*i.width*4])
-		}
-	} else if i.baseColor != nil {
-		r32, g32, b32, a32 := i.baseColor.RGBA()
-		r, g, b, a := uint8(r32), uint8(g32), uint8(b32), uint8(a32)
-		for idx := 0; idx < len(img.Pix)/4; idx++ {
-			img.Pix[4*idx] = r
-			img.Pix[4*idx+1] = g
-			img.Pix[4*idx+2] = b
-			img.Pix[4*idx+3] = a
-		}
-	}
 	var err error
-	i.image, err = graphics.NewImageFromImage(img, glFilter(i.filter))
+	i.image, err = i.restoringInfo.restore(context)
 	if err != nil {
 		return err
 	}
-	for _, c := range i.drawImageHistory {
-		if c.image.impl.hasHistory() {
-			panic("not reach")
-		}
-		if err := i.image.DrawImage(c.image.impl.image, c.vertices, &c.geom, &c.colorm, c.mode); err != nil {
-			return err
-		}
-	}
-	if 0 < len(i.drawImageHistory) {
-		i.pixels, err = i.image.Pixels(context)
-		if err != nil {
-			return err
-		}
-	}
-	i.baseColor = nil
-	i.drawImageHistory = nil
 	return nil
 }
 
@@ -326,9 +259,7 @@ func (i *imageImpl) Dispose() error {
 	}
 	i.image = nil
 	i.disposed = true
-	i.pixels = nil
-	i.baseColor = nil
-	i.drawImageHistory = nil
+	i.restoringInfo.clear()
 	runtime.SetFinalizer(i, nil)
 	return nil
 }
@@ -339,12 +270,7 @@ func (i *imageImpl) ReplacePixels(p []uint8) error {
 	}
 	i.m.Lock()
 	defer i.m.Unlock()
-	if i.pixels == nil {
-		i.pixels = make([]uint8, i.width*i.height*4)
-	}
-	copy(i.pixels, p)
-	i.baseColor = nil
-	i.drawImageHistory = nil
+	i.restoringInfo.resetWithPixels(p)
 	if i.disposed {
 		return errors.New("ebiten: image is already disposed")
 	}
diff --git a/imagerestoringinfo.go b/imagerestoringinfo.go
new file mode 100644
index 000000000..bc352526b
--- /dev/null
+++ b/imagerestoringinfo.go
@@ -0,0 +1,146 @@
+// Copyright 2016 Hajime Hoshi
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ebiten
+
+import (
+	"image"
+	"image/color"
+
+	"github.com/hajimehoshi/ebiten/internal/graphics"
+	"github.com/hajimehoshi/ebiten/internal/graphics/opengl"
+)
+
+type drawImageHistoryItem struct {
+	image    *Image
+	vertices []int16
+	geom     GeoM
+	colorm   ColorM
+	mode     opengl.CompositeMode
+}
+
+type imageRestoringInfo struct {
+	imageImpl        *imageImpl
+	pixels           []uint8
+	baseColor        color.Color
+	drawImageHistory []*drawImageHistoryItem
+}
+
+func (i *imageRestoringInfo) resetWithPixels(pixels []uint8) {
+	if i.pixels == nil {
+		i.pixels = make([]uint8, len(pixels))
+	}
+	copy(i.pixels, pixels)
+	i.baseColor = nil
+	i.drawImageHistory = nil
+}
+
+func (i *imageRestoringInfo) clear() {
+	i.pixels = nil
+	i.baseColor = nil
+	i.drawImageHistory = nil
+}
+
+func (i *imageRestoringInfo) fill(clr color.Color) {
+	i.pixels = nil
+	i.baseColor = clr
+	i.drawImageHistory = nil
+}
+
+func (i *imageRestoringInfo) appendDrawImageHistory(item *drawImageHistoryItem) {
+	i.drawImageHistory = append(i.drawImageHistory, item)
+}
+
+func (i *imageRestoringInfo) at(x, y int, context *opengl.Context) (color.Color, error) {
+	if i.pixels == nil || i.drawImageHistory != nil {
+		var err error
+		i.pixels, err = i.imageImpl.image.Pixels(context)
+		if err != nil {
+			return nil, err
+		}
+		i.baseColor = nil
+		i.drawImageHistory = nil
+	}
+	idx := 4*x + 4*y*i.imageImpl.width
+	r, g, b, a := i.pixels[idx], i.pixels[idx+1], i.pixels[idx+2], i.pixels[idx+3]
+	return color.RGBA{r, g, b, a}, nil
+}
+
+func (i *imageRestoringInfo) hasHistoryWith(target *Image) bool {
+	for _, c := range i.drawImageHistory {
+		if c.image == target {
+			return true
+		}
+	}
+	return false
+}
+
+func (i *imageRestoringInfo) resetHistoryIfNeeded(target *Image, context *opengl.Context) error {
+	if i.drawImageHistory == nil {
+		return nil
+	}
+	if !i.hasHistoryWith(target) {
+		return nil
+	}
+	var err error
+	i.pixels, err = i.imageImpl.image.Pixels(context)
+	if err != nil {
+		return err
+	}
+	i.baseColor = nil
+	i.drawImageHistory = nil
+	return nil
+}
+
+func (i *imageRestoringInfo) hasHistory() bool {
+	return i.drawImageHistory != nil
+}
+
+func (i *imageRestoringInfo) restore(context *opengl.Context) (*graphics.Image, error) {
+	w, h := i.imageImpl.width, i.imageImpl.height
+	img := image.NewRGBA(image.Rect(0, 0, w, h))
+	if i.pixels != nil {
+		for j := 0; j < h; j++ {
+			copy(img.Pix[j*img.Stride:], i.pixels[j*w*4:(j+1)*w*4])
+		}
+	} else if i.baseColor != nil {
+		r32, g32, b32, a32 := i.baseColor.RGBA()
+		r, g, b, a := uint8(r32), uint8(g32), uint8(b32), uint8(a32)
+		for idx := 0; idx < len(img.Pix)/4; idx++ {
+			img.Pix[4*idx] = r
+			img.Pix[4*idx+1] = g
+			img.Pix[4*idx+2] = b
+			img.Pix[4*idx+3] = a
+		}
+	}
+	gimg, err := graphics.NewImageFromImage(img, glFilter(i.imageImpl.filter))
+	if err != nil {
+		return nil, err
+	}
+	for _, c := range i.drawImageHistory {
+		if c.image.impl.hasHistory() {
+			panic("not reach")
+		}
+		if err := gimg.DrawImage(c.image.impl.image, c.vertices, &c.geom, &c.colorm, c.mode); err != nil {
+			return nil, err
+		}
+	}
+	i.pixels, err = gimg.Pixels(context)
+	if err != nil {
+		return nil, err
+	}
+	i.baseColor = nil
+	i.drawImageHistory = nil
+	return gimg, nil
+}