--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/TiffReader.cpp	Tue Jul 18 07:13:36 2023 +0200
@@ -0,0 +1,131 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2023 Osimis S.A., Belgium
+ * Copyright (C) 2021-2023 Sebastien Jodogne, ICTEAM UCLouvain, Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "TiffReader.h"
+
+#include <Logging.h>
+#include <OrthancException.h>
+
+namespace OrthancWSI
+{
+  TiffReader::TiffReader(const std::string& path)
+  {
+    tiff_ = TIFFOpen(path.c_str(), "r");
+    if (tiff_ == NULL)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_InexistentFile,
+                                      "libtiff cannot open: " + path);
+    }
+  }
+
+
+  TiffReader::~TiffReader()
+  {
+    if (tiff_)
+    {
+      TIFFClose(tiff_);
+      tiff_ = NULL;
+    }
+  }
+
+
+  bool TiffReader::GetCurrentDirectoryInformation(ImageCompression& compression,
+                                                  Orthanc::PixelFormat& pixelFormat,
+                                                  Orthanc::PhotometricInterpretation& photometric)
+  {
+    uint16_t c;
+    if (!TIFFGetField(tiff_, TIFFTAG_COMPRESSION, &c))
+    {
+      return false;
+    }
+
+    switch (c)
+    {
+      case COMPRESSION_NONE:
+        compression = ImageCompression_None;
+        break;
+
+      case COMPRESSION_JPEG:
+        compression = ImageCompression_Jpeg;
+        break;
+
+      default:
+        return false;
+    }
+
+    // http://www.awaresystems.be/imaging/tiff/tifftags/baseline.html
+
+    uint16_t channels, photometricTiff, bpp, planar;
+    if (!TIFFGetField(tiff_, TIFFTAG_SAMPLESPERPIXEL, &channels) ||
+        channels == 0 ||
+        !TIFFGetField(tiff_, TIFFTAG_PHOTOMETRIC, &photometricTiff) ||
+        !TIFFGetField(tiff_, TIFFTAG_BITSPERSAMPLE, &bpp) ||
+        !TIFFGetField(tiff_, TIFFTAG_PLANARCONFIG, &planar))
+    {
+      return false;
+    }
+
+    if (compression == ImageCompression_Jpeg &&
+        channels == 3 &&     // This is a color image
+        bpp == 8 &&
+        planar == PLANARCONFIG_CONTIG)  // This is interleaved RGB
+    {
+      pixelFormat = Orthanc::PixelFormat_RGB24;
+
+      switch (photometricTiff)
+      {
+        case PHOTOMETRIC_YCBCR:
+          photometric = Orthanc::PhotometricInterpretation_YBRFull422;
+          break;
+
+        case PHOTOMETRIC_RGB:
+          photometric = Orthanc::PhotometricInterpretation_RGB;
+          break;
+
+        default:
+          LOG(ERROR) << "Unknown photometric interpretation in TIFF: " << photometricTiff;
+          return false;
+      }
+    }
+    else if (compression == ImageCompression_None &&
+             channels == 3 &&     // This is a color image
+             bpp == 8 &&
+             planar == PLANARCONFIG_CONTIG)  // This is interleaved RGB
+    {
+      pixelFormat = Orthanc::PixelFormat_RGB24;
+      photometric = Orthanc::PhotometricInterpretation_RGB;
+    }
+    else if (compression == ImageCompression_Jpeg &&
+             channels == 1 &&     // This is a grayscale image
+             bpp == 8)
+    {
+      pixelFormat = Orthanc::PixelFormat_Grayscale8;
+      photometric = Orthanc::PhotometricInterpretation_Monochrome2;
+    }
+    else
+    {
+      return false;
+    }
+
+    return true;
+  }
+}