https://github.com/ImageMagick/ImageMagick/issues/1517

diff --git a/coders/dpx.c b/coders/dpx.c
index d69cd983fa9ed4af675053f9aabf2c1f7d766c7c..f30763ecbbff9cf789e26fe502dda45878751233 100644 (file)
--- a/coders/dpx.c
+++ b/coders/dpx.c
@@ -2022,8 +2022,10 @@ static MagickBooleanType WriteDPXImage(const ImageInfo *image_info,Image *image,
       break;
     length=ExportQuantumPixels(image,(CacheView *) NULL,quantum_info,
       quantum_type,pixels,exception);
+    if (length == 0)
+      break;
     count=WriteBlob(image,extent,pixels);
-    if (count != (ssize_t) length)
+    if (count != (ssize_t) extent)
       break;
     status=SetImageProgress(image,SaveImageTag,(MagickOffsetType) y,
       image->rows);