diff --git a/lib/imagereader/imagereader.cc b/lib/imagereader/imagereader.cc
index 5ea4d360..b1fa0c95 100644
--- a/lib/imagereader/imagereader.cc
+++ b/lib/imagereader/imagereader.cc
@@ -58,12 +58,10 @@ void ImageReader::updateConfigForFilename(ImageReaderProto* proto, const std::st
 		{".dim",      [&]() { proto->mutable_dim(); }},
 		{".diskcopy", [&]() { proto->mutable_diskcopy(); }},
 		{".fdi",      [&]() { proto->mutable_fdi(); }},
-		{".FDI",      [&]() { proto->mutable_fdi(); }},
 		{".img",      [&]() { proto->mutable_img(); }},
 		{".st",       [&]() { proto->mutable_img(); }},
 		{".nsi",      [&]() { proto->mutable_nsi(); }},
 		{".td0",      [&]() { proto->mutable_td0(); }},
-		{".TD0",      [&]() { proto->mutable_td0(); }},
 		{".xdf",      [&]() { proto->mutable_img(); }},
 	};
 
diff --git a/lib/utils.cc b/lib/utils.cc
index f9b09cc2..d25a127b 100644
--- a/lib/utils.cc
+++ b/lib/utils.cc
@@ -7,11 +7,15 @@ bool beginsWith(const std::string& value, const std::string& ending)
     return std::equal(ending.begin(), ending.end(), value.begin());
 }
 
+// Case-insensitive for endings within ASCII.
 bool endsWith(const std::string& value, const std::string& ending)
 {
     if (ending.size() > value.size())
         return false;
-    return std::equal(ending.rbegin(), ending.rend(), value.rbegin());
+    std::string lowercase(ending.size(), 0);
+    std::transform(value.rbegin(), value.rbegin() + ending.size(), lowercase.begin(), [](unsigned char c){ return std::tolower(c); });
+    return std::equal(ending.rbegin(), ending.rend(), value.rbegin()) ||
+        std::equal(ending.rbegin(), ending.rend(), lowercase.begin());
 }