diff --git a/3rdparty/libtiff/CMakeLists.txt b/3rdparty/libtiff/CMakeLists.txt
index addbb5551..5793021b7 100644
--- a/3rdparty/libtiff/CMakeLists.txt
+++ b/3rdparty/libtiff/CMakeLists.txt
@@ -6,6 +6,7 @@ project(${TIFF_LIBRARY})
 
 include(CheckFunctionExists)
 include(CheckIncludeFile)
+include(TestBigEndian)
 
 check_include_file(assert.h HAVE_ASSERT_H)
 check_include_file(fcntl.h HAVE_FCNTL_H)
@@ -16,6 +17,7 @@ check_include_file(search.h HAVE_SEARCH_H)
 check_include_file(string.h HAVE_STRING_H)
 check_include_file(sys/types.h HAVE_SYS_TYPES_H)
 check_include_file(unistd.h HAVE_UNISTD_H)
+test_big_endian(HOST_BIGENDIAN)
 
 if(WIN32 AND NOT HAVE_WINRT)
   set(USE_WIN32_FILEIO 1)
diff --git a/3rdparty/libtiff/tif_config.h.cmakein b/3rdparty/libtiff/tif_config.h.cmakein
index 182f2833d..55c6cb26a 100644
--- a/3rdparty/libtiff/tif_config.h.cmakein
+++ b/3rdparty/libtiff/tif_config.h.cmakein
@@ -54,7 +54,7 @@
 
 /* Native cpu byte order: 1 if big-endian (Motorola) or 0 if little-endian
    (Intel) */
-#define HOST_BIGENDIAN 0
+#define HOST_BIGENDIAN @HOST_BIGENDIAN@
 
 /* Set the native cpu bit order (FILLORDER_LSB2MSB or FILLORDER_MSB2LSB) */
 #define HOST_FILLORDER FILLORDER_LSB2MSB
diff --git a/modules/highgui/src/grfmt_tiff.cpp b/modules/highgui/src/grfmt_tiff.cpp
index 5179531f5..c86b4e365 100644
--- a/modules/highgui/src/grfmt_tiff.cpp
+++ b/modules/highgui/src/grfmt_tiff.cpp
@@ -111,18 +111,21 @@ bool TiffDecoder::readHeader()
     bool result = false;
 
     close();
-    TIFF* tif = TIFFOpen( m_filename.c_str(), "rb" );
+    // TIFFOpen() mode flags are different to fopen().  A 'b' in mode "rb" has no effect when reading.
+    // http://www.remotesensing.org/libtiff/man/TIFFOpen.3tiff.html
+    TIFF* tif = TIFFOpen( m_filename.c_str(), "r" );
 
     if( tif )
     {
-        int wdth = 0, hght = 0, photometric = 0;
+        uint wdth = 0, hght = 0;
+        ushort photometric = 0;
         m_tif = tif;
 
         if( TIFFGetField( tif, TIFFTAG_IMAGEWIDTH, &wdth ) &&
             TIFFGetField( tif, TIFFTAG_IMAGELENGTH, &hght ) &&
             TIFFGetField( tif, TIFFTAG_PHOTOMETRIC, &photometric ))
         {
-            int bpp=8, ncn = photometric > 1 ? 3 : 1;
+            ushort bpp=8, ncn = photometric > 1 ? 3 : 1;
             TIFFGetField( tif, TIFFTAG_BITSPERSAMPLE, &bpp );
             TIFFGetField( tif, TIFFTAG_SAMPLESPERPIXEL, &ncn );
 
@@ -175,12 +178,12 @@ bool  TiffDecoder::readData( Mat& img )
     if( m_tif && m_width && m_height )
     {
         TIFF* tif = (TIFF*)m_tif;
-        int tile_width0 = m_width, tile_height0 = 0;
+        uint tile_width0 = m_width, tile_height0 = 0;
         int x, y, i;
         int is_tiled = TIFFIsTiled(tif);
-        int photometric;
+        ushort photometric;
         TIFFGetField( tif, TIFFTAG_PHOTOMETRIC, &photometric );
-        int bpp = 8, ncn = photometric > 1 ? 3 : 1;
+        ushort bpp = 8, ncn = photometric > 1 ? 3 : 1;
         TIFFGetField( tif, TIFFTAG_BITSPERSAMPLE, &bpp );
         TIFFGetField( tif, TIFFTAG_SAMPLESPERPIXEL, &ncn );
         const int bitsPerByte = 8;
diff --git a/modules/highgui/test/test_grfmt.cpp b/modules/highgui/test/test_grfmt.cpp
index 86954e3e1..edccc0280 100644
--- a/modules/highgui/test/test_grfmt.cpp
+++ b/modules/highgui/test/test_grfmt.cpp
@@ -408,8 +408,8 @@ TEST(Highgui_Tiff, decode_tile16384x16384)
 
     try
     {
-        cv::imread(file3);
-        EXPECT_NO_THROW(cv::imread(file4));
+        cv::imread(file3, CV_LOAD_IMAGE_UNCHANGED);
+        EXPECT_NO_THROW(cv::imread(file4, CV_LOAD_IMAGE_UNCHANGED));
     }
     catch(const std::bad_alloc&)
     {
@@ -419,4 +419,52 @@ TEST(Highgui_Tiff, decode_tile16384x16384)
     remove(file3.c_str());
     remove(file4.c_str());
 }
+
+TEST(Highgui_Tiff, write_read_16bit_big_little_endian)
+{
+    // see issue #2601 "16-bit Grayscale TIFF Load Failures Due to Buffer Underflow and Endianness"
+
+    // Setup data for two minimal 16-bit grayscale TIFF files in both endian formats
+    uchar tiff_sample_data[2][86] = { {
+        // Little endian
+        0x49, 0x49, 0x2a, 0x00, 0x0c, 0x00, 0x00, 0x00, 0xad, 0xde, 0xef, 0xbe, 0x06, 0x00, 0x00, 0x01,
+        0x03, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x01, 0x01, 0x03, 0x00, 0x01, 0x00,
+        0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02, 0x01, 0x03, 0x00, 0x01, 0x00, 0x00, 0x00, 0x10, 0x00,
+        0x00, 0x00, 0x06, 0x01, 0x03, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x11, 0x01,
+        0x04, 0x00, 0x01, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x17, 0x01, 0x04, 0x00, 0x01, 0x00,
+        0x00, 0x00, 0x04, 0x00, 0x00, 0x00 }, {
+        // Big endian
+        0x4d, 0x4d, 0x00, 0x2a, 0x00, 0x00, 0x00, 0x0c, 0xde, 0xad, 0xbe, 0xef, 0x00, 0x06, 0x01, 0x00,
+        0x00, 0x03, 0x00, 0x00, 0x00, 0x01, 0x00, 0x02, 0x00, 0x00, 0x01, 0x01, 0x00, 0x03, 0x00, 0x00,
+        0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x01, 0x02, 0x00, 0x03, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10,
+        0x00, 0x00, 0x01, 0x06, 0x00, 0x03, 0x00, 0x00, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x01, 0x11,
+        0x00, 0x04, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x08, 0x01, 0x17, 0x00, 0x04, 0x00, 0x00,
+        0x00, 0x01, 0x00, 0x00, 0x00, 0x04 }
+        };
+
+    // Test imread() for both a little endian TIFF and big endian TIFF
+    for (int i = 0; i < 2; i++)
+    {
+        string filename = cv::tempfile(".tiff");
+
+        // Write sample TIFF file
+        FILE* fp = fopen(filename.c_str(), "wb");
+        ASSERT_TRUE(fp != NULL);
+        ASSERT_EQ((size_t)1, fwrite(tiff_sample_data, 86, 1, fp));
+        fclose(fp);
+
+        Mat img = imread(filename, CV_LOAD_IMAGE_UNCHANGED);
+
+        EXPECT_EQ(1, img.rows);
+        EXPECT_EQ(2, img.cols);
+        EXPECT_EQ(CV_16U, img.type());
+        EXPECT_EQ(sizeof(ushort), img.elemSize());
+        EXPECT_EQ(1, img.channels());
+        EXPECT_EQ(0xDEAD, img.at<ushort>(0,0));
+        EXPECT_EQ(0xBEEF, img.at<ushort>(0,1));
+
+        remove(filename.c_str());
+    }
+}
+
 #endif