diff --git a/src/document.cpp b/src/document.cpp
index c43512dc..e1175b4c 100644
--- a/src/document.cpp
+++ b/src/document.cpp
@@ -7,6 +7,7 @@
 #include <QApplication>
 #include <QVector3D>
 #include <functional>
+#include <QBuffer>
 #include "document.h"
 #include "util.h"
 #include "snapshotxml.h"
@@ -719,6 +720,10 @@ void Document::setNodeBoneMark(QUuid nodeId, BoneMark mark)
 void Document::updateTurnaround(const QImage &image)
 {
     turnaround = image;
+    turnaroundPngByteArray.clear();
+    QBuffer pngBuffer(&turnaroundPngByteArray);
+    pngBuffer.open(QIODevice::WriteOnly);
+    turnaround.save(&pngBuffer, "PNG");
     emit turnaroundChanged();
 }
 
diff --git a/src/documentwindow.cpp b/src/documentwindow.cpp
index 4ec43de1..8ad85a65 100644
--- a/src/documentwindow.cpp
+++ b/src/documentwindow.cpp
@@ -1102,13 +1102,8 @@ void DocumentWindow::saveTo(const QString &saveAsFilename)
     if (modelXml.size() > 0)
         ds3Writer.add("model.xml", "model", &modelXml);
 
-    QByteArray imageByteArray;
-    QBuffer pngBuffer(&imageByteArray);
-    if (!m_document->turnaround.isNull()) {
-        pngBuffer.open(QIODevice::WriteOnly);
-        m_document->turnaround.save(&pngBuffer, "PNG");
-        if (imageByteArray.size() > 0)
-            ds3Writer.add("canvas.png", "asset", &imageByteArray);
+    if (!m_document->turnaround.isNull() && m_document->turnaroundPngByteArray.size() > 0) {
+        ds3Writer.add("canvas.png", "asset", &m_document->turnaroundPngByteArray);
     }
     
     std::set<QUuid> imageIds;
@@ -1133,15 +1128,11 @@ void DocumentWindow::saveTo(const QString &saveAsFilename)
     }
     
     for (const auto &imageId: imageIds) {
-        const QImage *image = ImageForever::get(imageId);
-        if (nullptr == image)
+        const QByteArray *pngByteArray = ImageForever::getPngByteArray(imageId);
+        if (nullptr == pngByteArray)
             continue;
-        QByteArray imageByteArray;
-        QBuffer pngBuffer(&imageByteArray);
-        pngBuffer.open(QIODevice::WriteOnly);
-        image->save(&pngBuffer, "PNG");
-        if (imageByteArray.size() > 0)
-            ds3Writer.add("images/" + imageId.toString() + ".png", "asset", &imageByteArray);
+        if (pngByteArray->size() > 0)
+            ds3Writer.add("images/" + imageId.toString() + ".png", "asset", pngByteArray);
     }
 
     if (ds3Writer.save(filename)) {
diff --git a/src/imageforever.cpp b/src/imageforever.cpp
index d58a885f..e397104e 100644
--- a/src/imageforever.cpp
+++ b/src/imageforever.cpp
@@ -1,12 +1,14 @@
 #include <map>
 #include <QMutex>
 #include <QMutexLocker>
+#include <QBuffer>
 #include "imageforever.h"
 
 struct ImageForeverItem
 {
     QImage *image;
     QUuid id;
+    QByteArray *imageByteArray;
 };
 static std::map<QUuid, ImageForeverItem> g_foreverMap;
 static std::map<qint64, QUuid> g_foreverCacheKeyToIdMap;
@@ -21,6 +23,15 @@ const QImage *ImageForever::get(const QUuid &id)
     return findResult->second.image;
 }
 
+const QByteArray *ImageForever::getPngByteArray(const QUuid &id)
+{
+    QMutexLocker locker(&g_mapMutex);
+    auto findResult = g_foreverMap.find(id);
+    if (findResult == g_foreverMap.end())
+        return nullptr;
+    return findResult->second.imageByteArray;
+}
+
 QUuid ImageForever::add(const QImage *image, QUuid toId)
 {
     QMutexLocker locker(&g_mapMutex);
@@ -35,7 +46,11 @@ QUuid ImageForever::add(const QImage *image, QUuid toId)
     if (g_foreverMap.find(newId) != g_foreverMap.end())
         return newId;
     QImage *newImage = new QImage(*image);
-    g_foreverMap[newId] = {newImage, newId};
+    QByteArray *imageByteArray = new QByteArray();
+    QBuffer pngBuffer(imageByteArray);
+    pngBuffer.open(QIODevice::WriteOnly);
+    newImage->save(&pngBuffer, "PNG");
+    g_foreverMap[newId] = {newImage, newId, imageByteArray};
     g_foreverCacheKeyToIdMap[newImage->cacheKey()] = newId;
     return newId;
 }
diff --git a/src/imageforever.h b/src/imageforever.h
index 769f598c..e843f650 100644
--- a/src/imageforever.h
+++ b/src/imageforever.h
@@ -2,11 +2,13 @@
 #define DUST3D_IMAGE_FOREVER_H
 #include <QImage>
 #include <QUuid>
+#include <QByteArray>
 
 class ImageForever
 {
 public:
     static const QImage *get(const QUuid &id);
+    static const QByteArray *getPngByteArray(const QUuid &id);
     static QUuid add(const QImage *image, QUuid toId=QUuid());
 };
 
diff --git a/src/skeletondocument.h b/src/skeletondocument.h
index 6050a81d..bb3d1494 100644
--- a/src/skeletondocument.h
+++ b/src/skeletondocument.h
@@ -5,6 +5,7 @@
 #include <QString>
 #include <cmath>
 #include <QImage>
+#include <QByteArray>
 #include "bonemark.h"
 #include "theme.h"
 #include "meshloader.h"
@@ -200,6 +201,7 @@ public:
     bool zlocked = false;
     bool radiusLocked = false;
     QImage turnaround;
+    QByteArray turnaroundPngByteArray;
     std::map<QUuid, SkeletonPart> partMap;
     std::map<QUuid, SkeletonNode> nodeMap;
     std::map<QUuid, SkeletonEdge> edgeMap;