diff --git a/coders/jbig.c b/coders/jbig.c
index 9d11b8f..36ca5b4 100644
--- a/coders/jbig.c
+++ b/coders/jbig.c
@@ -446,7 +446,8 @@
     /*
       Allocate pixel data.
     */
-    if (IssRGBColorspace(image->colorspace) == MagickFalse)
+    if ((IssRGBColorspace(image->colorspace) == MagickFalse) &&
+        (IsImageGray(image,exception) == MagickFalse))
       (void) TransformImageColorspace(image,sRGBColorspace,exception);
     number_packets=(image->columns+7)/8;
     pixels=(unsigned char *) AcquireQuantumMemory(number_packets,