diff --git a/pdfminer/pdfinterp.py b/pdfminer/pdfinterp.py
index c1a85973..7d7da4f9 100644
--- a/pdfminer/pdfinterp.py
+++ b/pdfminer/pdfinterp.py
@@ -938,7 +938,7 @@ def do_ID(self) -> None:
 
     def do_EI(self, obj: PDFStackT) -> None:
         """End inline image object"""
-        if isinstance(obj, PDFStream) and "W" in obj and "H" in obj:
+        if isinstance(obj, PDFStream) and hasattr(obj, 'W') and hasattr(obj, 'H'):
             iobjid = str(id(obj))
             self.device.begin_figure(iobjid, (0, 0, 1, 1), MATRIX_IDENTITY)
             self.device.render_image(iobjid, obj)