diff --git a/common/basetilecreator.go b/common/basetilecreator.go
index 9e02df5..397411e 100644
--- a/common/basetilecreator.go
+++ b/common/basetilecreator.go
@@ -172,7 +172,7 @@ func (btc *BaseTileCreator) CreateTile(x, z int16, i, j int) (bool, error) {
 		return true, SaveAsPNG(path, image)
 	}
 
-	if btc.update(i, j, SHA1Image(image)) {
+	if btc.update(i, j, HashImage(image)) {
 		log.Printf("Writing (%d, %d) to file %s.\n", x, z, path)
 		return true, SaveAsPNGAtomic(path, image)
 	}
diff --git a/common/image.go b/common/image.go
index b2feeee..2fed583 100644
--- a/common/image.go
+++ b/common/image.go
@@ -7,7 +7,6 @@ package common
 import (
 	"bufio"
 	"bytes"
-	"crypto/sha1"
 	"errors"
 	"image"
 	"image/color"
@@ -18,6 +17,8 @@ import (
 	"sync"
 	"time"
 
+	"golang.org/x/crypto/blake2b"
+
 	"github.com/bamiaux/rez"
 )
 
@@ -112,9 +113,9 @@ func LoadPNG(path string, bg color.RGBA) image.Image {
 	return img
 }
 
-func SHA1Image(img *image.RGBA) []byte {
+func HashImage(img *image.RGBA) []byte {
 
-	hash := sha1.New()
+	hash, _ := blake2b.New256(nil)
 	w, h := img.Rect.Dx()*4, img.Rect.Dy()
 
 	pos := img.PixOffset(img.Rect.Min.X, img.Rect.Min.Y)