From 642e5687b69bf62a6b5725a1415a2c072f0141eb Mon Sep 17 00:00:00 2001
From: Lovell Fuller <github@lovell.info>
Date: Sat, 11 Jul 2015 22:56:18 +0100
Subject: [PATCH] Guard against unexpected overlay band format #97

---
 src/pipeline.cc | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/pipeline.cc b/src/pipeline.cc
index 674879ba..21b7334d 100755
--- a/src/pipeline.cc
+++ b/src/pipeline.cc
@@ -726,6 +726,16 @@ class PipelineWorker : public NanAsyncWorker {
         (baton->err).append("Overlay image is of an unsupported image format");
         return Error();
       }
+      if (image->BandFmt != VIPS_FORMAT_UCHAR && image->BandFmt != VIPS_FORMAT_FLOAT) {
+        (baton->err).append("Expected image band format to be uchar or float: ");
+        (baton->err).append(vips_enum_nick(VIPS_TYPE_BAND_FORMAT, image->BandFmt));
+        return Error();
+      }
+      if (overlayImage->BandFmt != VIPS_FORMAT_UCHAR && overlayImage->BandFmt != VIPS_FORMAT_FLOAT) {
+        (baton->err).append("Expected overlay image band format to be uchar or float: ");
+        (baton->err).append(vips_enum_nick(VIPS_TYPE_BAND_FORMAT, overlayImage->BandFmt));
+        return Error();
+      }
       if (!HasAlpha(overlayImage)) {
         (baton->err).append("Overlay image must have an alpha channel");
         return Error();