diff --git a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG3Tag.java b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG3Tag.java
index 2b2323bb2..9a24574f0 100644
--- a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG3Tag.java
+++ b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG3Tag.java
@@ -135,6 +135,10 @@ public class DefineBitsJPEG3Tag extends ImageTag implements AloneTag {
         setModified(true);
     }
 
+    public byte[] getImageAlpha() throws IOException {
+        return SWFInputStream.uncompressByteArray(bitmapAlphaData.getRangeData());
+    }
+
     public void setImageAlpha(byte[] data) throws IOException {
         ImageFormat fmt = ImageTag.getImageFormat(imageData);
         if (fmt != ImageFormat.JPEG) {
@@ -194,7 +198,7 @@ public class DefineBitsJPEG3Tag extends ImageTag implements AloneTag {
                 return img;
             }
 
-            byte[] alphaData = SWFInputStream.uncompressByteArray(bitmapAlphaData.getRangeData());
+            byte[] alphaData = getImageAlpha();
             int[] pixels = ((DataBufferInt) img.getRaster().getDataBuffer()).getData();
             for (int i = 0; i < pixels.length; i++) {
                 int a = alphaData[i] & 0xff;
diff --git a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG4Tag.java b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG4Tag.java
index 38e7a6baf..b7532ca92 100644
--- a/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG4Tag.java
+++ b/libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineBitsJPEG4Tag.java
@@ -140,6 +140,10 @@ public class DefineBitsJPEG4Tag extends ImageTag implements AloneTag {
         setModified(true);
     }
 
+    public byte[] getImageAlpha() throws IOException {
+        return SWFInputStream.uncompressByteArray(bitmapAlphaData.getRangeData());
+    }
+
     public void setImageAlpha(byte[] data) throws IOException {
         ImageFormat fmt = ImageTag.getImageFormat(imageData);
         if (fmt != ImageFormat.JPEG) {
@@ -195,7 +199,7 @@ public class DefineBitsJPEG4Tag extends ImageTag implements AloneTag {
                 return img;
             }
 
-            byte[] alphaData = SWFInputStream.uncompressByteArray(bitmapAlphaData.getRangeData());
+            byte[] alphaData = getImageAlpha();
             int[] pixels = ((DataBufferInt) img.getRaster().getDataBuffer()).getData();
             for (int i = 0; i < pixels.length; i++) {
                 int a = alphaData[i] & 0xff;
diff --git a/src/com/jpexs/decompiler/flash/gui/MainPanel.java b/src/com/jpexs/decompiler/flash/gui/MainPanel.java
index 7b29e337d..caeaa7c4d 100644
--- a/src/com/jpexs/decompiler/flash/gui/MainPanel.java
+++ b/src/com/jpexs/decompiler/flash/gui/MainPanel.java
@@ -2611,7 +2611,7 @@ public final class MainPanel extends JPanel implements TreeSelectionListener, Se
                         SWF swf = it.getSwf();
                         swf.clearImageCache();
                     } catch (IOException ex) {
-                        logger.log(Level.SEVERE, "Invalid image", ex);
+                        logger.log(Level.SEVERE, "Invalid alpha channel data", ex);
                         View.showMessageDialog(null, translate("error.image.invalid"), translate("error"), JOptionPane.ERROR_MESSAGE);
                     }
 
diff --git a/src/com/jpexs/decompiler/flash/gui/locales/MainFrame.properties b/src/com/jpexs/decompiler/flash/gui/locales/MainFrame.properties
index 8ad471245..1d71f84a6 100644
--- a/src/com/jpexs/decompiler/flash/gui/locales/MainFrame.properties
+++ b/src/com/jpexs/decompiler/flash/gui/locales/MainFrame.properties
@@ -625,3 +625,4 @@ import.script.result = %count% scripts imported.
 import.script.as12warning = Import script can import only AS1/2 scripts.
 
 error.constantPoolTooBig = Constant pool is too big. index=%index%, size=%size%
+error.image.alpha.invalid = Invalid alpha channel data.
diff --git a/src/com/jpexs/decompiler/flash/gui/locales/MainFrame_hu.properties b/src/com/jpexs/decompiler/flash/gui/locales/MainFrame_hu.properties
index 228452542..040d889ba 100644
--- a/src/com/jpexs/decompiler/flash/gui/locales/MainFrame_hu.properties
+++ b/src/com/jpexs/decompiler/flash/gui/locales/MainFrame_hu.properties
@@ -624,3 +624,4 @@ import.script.result = %count% szkript import\u00e1lva.
 import.script.as12warning = A szkript import\u00e1l\u00e1s csak AS1/2 szkriptekre m\u0171k\u00f6dik.
 
 error.constantPoolTooBig = Karakter l\u00e1nc t\u00e1rol\u00f3 t\u00fal nagy. index=%index%, m\u00e9ret=%size%
+error.image.alpha.invalid = \u00c9rv\u00e9nytelen alfa csatorna adat.