diff --git a/src/lib/OpenEXR/ImfMultiPartInputFile.h b/src/lib/OpenEXR/ImfMultiPartInputFile.h
index b83ea9843b..69be13a12e 100644
--- a/src/lib/OpenEXR/ImfMultiPartInputFile.h
+++ b/src/lib/OpenEXR/ImfMultiPartInputFile.h
@@ -111,6 +111,8 @@ class IMF_EXPORT_TYPE MultiPartInputFile : public GenericInputFile
     friend class ScanLineInputFile;
     friend class DeepScanLineInputFile;
     friend class DeepTiledInputFile;
+
+    friend class RgbaInputFile;
 };
 
 
diff --git a/src/lib/OpenEXR/ImfRgbaFile.cpp b/src/lib/OpenEXR/ImfRgbaFile.cpp
index 47b87dee26..acd96257fa 100644
--- a/src/lib/OpenEXR/ImfRgbaFile.cpp
+++ b/src/lib/OpenEXR/ImfRgbaFile.cpp
@@ -13,6 +13,7 @@
 #include <ImfRgbaFile.h>
 #include <ImfOutputFile.h>
 #include <ImfInputFile.h>
+#include <ImfMultiPartInputFile.h>
 #include <ImfChannelList.h>
 #include <ImfRgbaYca.h>
 #include <ImfStandardAttributes.h>
@@ -1164,6 +1165,20 @@ RgbaInputFile::RgbaInputFile (const char name[], int numThreads):
 }
 
 
+RgbaInputFile::RgbaInputFile (int partNumber, const char name[], int numThreads):
+    _inputFile (0),
+    _fromYca (0),
+    _channelNamePrefix ("")
+{
+    _multiPartFile = new MultiPartInputFile(name, numThreads);
+    _inputFile = _multiPartFile->getInputPart<InputFile>(partNumber);
+    RgbaChannels rgbaChannels = channels();
+
+    if (rgbaChannels & (WRITE_Y | WRITE_C))
+	_fromYca = new FromYca (*_inputFile, rgbaChannels);
+}
+
+
 RgbaInputFile::RgbaInputFile (OPENEXR_IMF_INTERNAL_NAMESPACE::IStream &is, int numThreads):
     _inputFile (new InputFile (is, numThreads)),
     _fromYca (0),
@@ -1208,7 +1223,10 @@ RgbaInputFile::RgbaInputFile (OPENEXR_IMF_INTERNAL_NAMESPACE::IStream &is,
 
 RgbaInputFile::~RgbaInputFile ()
 {
-    delete _inputFile;
+    if (_multiPartFile)
+        delete _multiPartFile;
+    else
+        delete _inputFile;
     delete _fromYca;
 }
 
diff --git a/src/lib/OpenEXR/ImfRgbaFile.h b/src/lib/OpenEXR/ImfRgbaFile.h
index fc4b2b7511..7379642687 100644
--- a/src/lib/OpenEXR/ImfRgbaFile.h
+++ b/src/lib/OpenEXR/ImfRgbaFile.h
@@ -292,6 +292,10 @@ class IMF_EXPORT_TYPE RgbaInputFile
     RgbaInputFile (const char name[], int numThreads = globalThreadCount());
 
 
+    IMF_EXPORT
+    RgbaInputFile (int partNumber, const char name[], int numThreads = globalThreadCount());
+
+
     //-----------------------------------------------------------
     // Constructor -- attaches the new RgbaInputFile object to a
     // file that has already been opened by the caller.
@@ -412,6 +416,7 @@ class IMF_EXPORT_TYPE RgbaInputFile
     InputFile *			_inputFile;
     FromYca *			_fromYca;
     std::string			_channelNamePrefix;
+    MultiPartInputFile* _multiPartFile = nullptr;
 };