--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancFramework/Sources/DicomFormat/DicomMap.cpp	Wed Jun 10 20:30:34 2020 +0200
@@ -0,0 +1,1424 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders of this
+ * program give permission to link the code of its release with the
+ * OpenSSL project's "OpenSSL" library (or with modified versions of it
+ * that use the same license as the "OpenSSL" library), and distribute
+ * the linked executables. You must obey the GNU General Public License
+ * in all respects for all of the code used other than "OpenSSL". If you
+ * modify file(s) with this exception, you may extend this exception to
+ * your version of the file(s), but you are not obligated to do so. If
+ * you do not wish to do so, delete this exception statement from your
+ * version. If you delete this exception statement from all source files
+ * in the program, then also delete it here.
+ * 
+ * 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "../PrecompiledHeaders.h"
+#include "DicomMap.h"
+
+#include <stdio.h>
+#include <memory>
+
+#include "../Compatibility.h"
+#include "../Endianness.h"
+#include "../Logging.h"
+#include "../OrthancException.h"
+#include "../Toolbox.h"
+#include "DicomArray.h"
+
+
+namespace Orthanc
+{
+  namespace
+  {
+    struct MainDicomTag
+    {
+      const DicomTag tag_;
+      const char*    name_;
+    };
+  }
+
+  static const MainDicomTag PATIENT_MAIN_DICOM_TAGS[] =
+  {
+    // { DicomTag(0x0010, 0x1010), "PatientAge" },
+    // { DicomTag(0x0010, 0x1040), "PatientAddress" },
+    { DicomTag(0x0010, 0x0010), "PatientName" },
+    { DicomTag(0x0010, 0x0030), "PatientBirthDate" },
+    { DicomTag(0x0010, 0x0040), "PatientSex" },
+    { DicomTag(0x0010, 0x1000), "OtherPatientIDs" },
+    { DICOM_TAG_PATIENT_ID, "PatientID" }
+  };
+    
+  static const MainDicomTag STUDY_MAIN_DICOM_TAGS[] =
+  {
+    // { DicomTag(0x0010, 0x1020), "PatientSize" },
+    // { DicomTag(0x0010, 0x1030), "PatientWeight" },
+    { DICOM_TAG_STUDY_DATE, "StudyDate" },
+    { DicomTag(0x0008, 0x0030), "StudyTime" },
+    { DicomTag(0x0020, 0x0010), "StudyID" },
+    { DICOM_TAG_STUDY_DESCRIPTION, "StudyDescription" },
+    { DICOM_TAG_ACCESSION_NUMBER, "AccessionNumber" },
+    { DICOM_TAG_STUDY_INSTANCE_UID, "StudyInstanceUID" },
+
+    // New in db v6
+    { DICOM_TAG_REQUESTED_PROCEDURE_DESCRIPTION, "RequestedProcedureDescription" },
+    { DICOM_TAG_INSTITUTION_NAME, "InstitutionName" },
+    { DICOM_TAG_REQUESTING_PHYSICIAN, "RequestingPhysician" },
+    { DICOM_TAG_REFERRING_PHYSICIAN_NAME, "ReferringPhysicianName" }
+  };
+    
+  static const MainDicomTag SERIES_MAIN_DICOM_TAGS[] =
+  {
+    // { DicomTag(0x0010, 0x1080), "MilitaryRank" },
+    { DicomTag(0x0008, 0x0021), "SeriesDate" },
+    { DicomTag(0x0008, 0x0031), "SeriesTime" },
+    { DICOM_TAG_MODALITY, "Modality" },
+    { DicomTag(0x0008, 0x0070), "Manufacturer" },
+    { DicomTag(0x0008, 0x1010), "StationName" },
+    { DICOM_TAG_SERIES_DESCRIPTION, "SeriesDescription" },
+    { DicomTag(0x0018, 0x0015), "BodyPartExamined" },
+    { DicomTag(0x0018, 0x0024), "SequenceName" },
+    { DicomTag(0x0018, 0x1030), "ProtocolName" },
+    { DicomTag(0x0020, 0x0011), "SeriesNumber" },
+    { DICOM_TAG_CARDIAC_NUMBER_OF_IMAGES, "CardiacNumberOfImages" },
+    { DICOM_TAG_IMAGES_IN_ACQUISITION, "ImagesInAcquisition" },
+    { DICOM_TAG_NUMBER_OF_TEMPORAL_POSITIONS, "NumberOfTemporalPositions" },
+    { DICOM_TAG_NUMBER_OF_SLICES, "NumberOfSlices" },
+    { DICOM_TAG_NUMBER_OF_TIME_SLICES, "NumberOfTimeSlices" },
+    { DICOM_TAG_SERIES_INSTANCE_UID, "SeriesInstanceUID" },
+
+    // New in db v6
+    { DICOM_TAG_IMAGE_ORIENTATION_PATIENT, "ImageOrientationPatient" },
+    { DICOM_TAG_SERIES_TYPE, "SeriesType" },
+    { DICOM_TAG_OPERATOR_NAME, "OperatorsName" },
+    { DICOM_TAG_PERFORMED_PROCEDURE_STEP_DESCRIPTION, "PerformedProcedureStepDescription" },
+    { DICOM_TAG_ACQUISITION_DEVICE_PROCESSING_DESCRIPTION, "AcquisitionDeviceProcessingDescription" },
+    { DICOM_TAG_CONTRAST_BOLUS_AGENT, "ContrastBolusAgent" }
+  };
+    
+  static const MainDicomTag INSTANCE_MAIN_DICOM_TAGS[] =
+  {
+    { DicomTag(0x0008, 0x0012), "InstanceCreationDate" },
+    { DicomTag(0x0008, 0x0013), "InstanceCreationTime" },
+    { DicomTag(0x0020, 0x0012), "AcquisitionNumber" },
+    { DICOM_TAG_IMAGE_INDEX, "ImageIndex" },
+    { DICOM_TAG_INSTANCE_NUMBER, "InstanceNumber" },
+    { DICOM_TAG_NUMBER_OF_FRAMES, "NumberOfFrames" },
+    { DICOM_TAG_TEMPORAL_POSITION_IDENTIFIER, "TemporalPositionIdentifier" },
+    { DICOM_TAG_SOP_INSTANCE_UID, "SOPInstanceUID" },
+
+    // New in db v6
+    { DICOM_TAG_IMAGE_POSITION_PATIENT, "ImagePositionPatient" },
+    { DICOM_TAG_IMAGE_COMMENTS, "ImageComments" },
+
+    /**
+     * Main DICOM tags that are not part of any release of the
+     * database schema yet, and that will be part of future db v7. In
+     * the meantime, the user must call "/tools/reconstruct" once to
+     * access these tags if the corresponding DICOM files where
+     * indexed in the database by an older version of Orthanc.
+     **/
+    { DICOM_TAG_IMAGE_ORIENTATION_PATIENT, "ImageOrientationPatient" }  // New in Orthanc 1.4.2
+  };
+
+
+  static void LoadMainDicomTags(const MainDicomTag*& tags,
+                                size_t& size,
+                                ResourceType level)
+  {
+    switch (level)
+    {
+      case ResourceType_Patient:
+        tags = PATIENT_MAIN_DICOM_TAGS;
+        size = sizeof(PATIENT_MAIN_DICOM_TAGS) / sizeof(MainDicomTag);
+        break;
+
+      case ResourceType_Study:
+        tags = STUDY_MAIN_DICOM_TAGS;
+        size = sizeof(STUDY_MAIN_DICOM_TAGS) / sizeof(MainDicomTag);
+        break;
+
+      case ResourceType_Series:
+        tags = SERIES_MAIN_DICOM_TAGS;
+        size = sizeof(SERIES_MAIN_DICOM_TAGS) / sizeof(MainDicomTag);
+        break;
+
+      case ResourceType_Instance:
+        tags = INSTANCE_MAIN_DICOM_TAGS;
+        size = sizeof(INSTANCE_MAIN_DICOM_TAGS) / sizeof(MainDicomTag);
+        break;
+
+      default:
+        throw OrthancException(ErrorCode_ParameterOutOfRange);
+    }
+  }
+
+
+  static void LoadMainDicomTags(std::map<DicomTag, std::string>& target,
+                                ResourceType level)
+  {
+    const MainDicomTag* tags = NULL;
+    size_t size;
+    LoadMainDicomTags(tags, size, level);
+
+    assert(tags != NULL &&
+           size != 0);
+
+    for (size_t i = 0; i < size; i++)
+    {
+      assert(target.find(tags[i].tag_) == target.end());
+      
+      target[tags[i].tag_] = tags[i].name_;
+    }
+  }
+
+
+  namespace
+  {
+    class DicomTag2 : public DicomTag
+    {
+    public:
+      DicomTag2() :
+        DicomTag(0, 0)   // To make std::map<> happy
+      {
+      }
+
+      DicomTag2(const DicomTag& tag) :
+        DicomTag(tag)
+      {
+      }
+    };
+  }
+
+
+  static void LoadMainDicomTags(std::map<std::string, DicomTag2>& target,
+                                ResourceType level)
+  {
+    const MainDicomTag* tags = NULL;
+    size_t size;
+    LoadMainDicomTags(tags, size, level);
+
+    assert(tags != NULL &&
+           size != 0);
+
+    for (size_t i = 0; i < size; i++)
+    {
+      assert(target.find(tags[i].name_) == target.end());
+      
+      target[tags[i].name_] = tags[i].tag_;
+    }
+  }
+
+
+  void DicomMap::SetValueInternal(uint16_t group, 
+                                  uint16_t element, 
+                                  DicomValue* value)
+  {
+    DicomTag tag(group, element);
+    Content::iterator it = content_.find(tag);
+
+    if (it != content_.end())
+    {
+      delete it->second;
+      it->second = value;
+    }
+    else
+    {
+      content_.insert(std::make_pair(tag, value));
+    }
+  }
+
+
+  void DicomMap::Clear()
+  {
+    for (Content::iterator it = content_.begin(); it != content_.end(); ++it)
+    {
+      assert(it->second != NULL);
+      delete it->second;
+    }
+
+    content_.clear();
+  }
+
+
+  static void ExtractTags(DicomMap& result,
+                          const DicomMap::Content& source,
+                          const MainDicomTag* tags,
+                          size_t count)
+  {
+    result.Clear();
+
+    for (unsigned int i = 0; i < count; i++)
+    {
+      DicomMap::Content::const_iterator it = source.find(tags[i].tag_);
+      if (it != source.end())
+      {
+        result.SetValue(it->first, *it->second /* value will be cloned */);
+      }
+    }
+  }
+
+
+  void DicomMap::ExtractPatientInformation(DicomMap& result) const
+  {
+    ExtractTags(result, content_, PATIENT_MAIN_DICOM_TAGS, sizeof(PATIENT_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+  }
+
+  void DicomMap::ExtractStudyInformation(DicomMap& result) const
+  {
+    ExtractTags(result, content_, STUDY_MAIN_DICOM_TAGS, sizeof(STUDY_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+  }
+
+  void DicomMap::ExtractSeriesInformation(DicomMap& result) const
+  {
+    ExtractTags(result, content_, SERIES_MAIN_DICOM_TAGS, sizeof(SERIES_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+  }
+
+  void DicomMap::ExtractInstanceInformation(DicomMap& result) const
+  {
+    ExtractTags(result, content_, INSTANCE_MAIN_DICOM_TAGS, sizeof(INSTANCE_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+  }
+
+
+
+  DicomMap* DicomMap::Clone() const
+  {
+    std::unique_ptr<DicomMap> result(new DicomMap);
+
+    for (Content::const_iterator it = content_.begin(); it != content_.end(); ++it)
+    {
+      result->content_.insert(std::make_pair(it->first, it->second->Clone()));
+    }
+
+    return result.release();
+  }
+
+
+  void DicomMap::Assign(const DicomMap& other)
+  {
+    Clear();
+
+    for (Content::const_iterator it = other.content_.begin(); it != other.content_.end(); ++it)
+    {
+      content_.insert(std::make_pair(it->first, it->second->Clone()));
+    }
+  }
+
+
+  const DicomValue& DicomMap::GetValue(const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value)
+    {
+      return *value;
+    }
+    else
+    {
+      throw OrthancException(ErrorCode_InexistentTag);
+    }
+  }
+
+
+  const DicomValue* DicomMap::TestAndGetValue(const DicomTag& tag) const
+  {
+    Content::const_iterator it = content_.find(tag);
+
+    if (it == content_.end())
+    {
+      return NULL;
+    }
+    else
+    {
+      return it->second;
+    }
+  }
+
+
+  void DicomMap::Remove(const DicomTag& tag) 
+  {
+    Content::iterator it = content_.find(tag);
+    if (it != content_.end())
+    {
+      delete it->second;
+      content_.erase(it);
+    }
+  }
+
+
+  static void SetupFindTemplate(DicomMap& result,
+                                const MainDicomTag* tags,
+                                size_t count) 
+  {
+    result.Clear();
+
+    for (size_t i = 0; i < count; i++)
+    {
+      result.SetValue(tags[i].tag_, "", false);
+    }
+  }
+
+  void DicomMap::SetupFindPatientTemplate(DicomMap& result)
+  {
+    SetupFindTemplate(result, PATIENT_MAIN_DICOM_TAGS, sizeof(PATIENT_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+  }
+
+  void DicomMap::SetupFindStudyTemplate(DicomMap& result)
+  {
+    SetupFindTemplate(result, STUDY_MAIN_DICOM_TAGS, sizeof(STUDY_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+    result.SetValue(DICOM_TAG_ACCESSION_NUMBER, "", false);
+    result.SetValue(DICOM_TAG_PATIENT_ID, "", false);
+
+    // These main DICOM tags are only indirectly related to the
+    // General Study Module, remove them
+    result.Remove(DICOM_TAG_INSTITUTION_NAME);
+    result.Remove(DICOM_TAG_REQUESTING_PHYSICIAN);
+    result.Remove(DICOM_TAG_REQUESTED_PROCEDURE_DESCRIPTION);
+  }
+
+  void DicomMap::SetupFindSeriesTemplate(DicomMap& result)
+  {
+    SetupFindTemplate(result, SERIES_MAIN_DICOM_TAGS, sizeof(SERIES_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+    result.SetValue(DICOM_TAG_ACCESSION_NUMBER, "", false);
+    result.SetValue(DICOM_TAG_PATIENT_ID, "", false);
+    result.SetValue(DICOM_TAG_STUDY_INSTANCE_UID, "", false);
+
+    // These tags are considered as "main" by Orthanc, but are not in the Series module
+    result.Remove(DicomTag(0x0008, 0x0070));  // Manufacturer
+    result.Remove(DicomTag(0x0008, 0x1010));  // Station name
+    result.Remove(DicomTag(0x0018, 0x0024));  // Sequence name
+    result.Remove(DICOM_TAG_CARDIAC_NUMBER_OF_IMAGES);
+    result.Remove(DICOM_TAG_IMAGES_IN_ACQUISITION);
+    result.Remove(DICOM_TAG_NUMBER_OF_SLICES);
+    result.Remove(DICOM_TAG_NUMBER_OF_TEMPORAL_POSITIONS);
+    result.Remove(DICOM_TAG_NUMBER_OF_TIME_SLICES);
+    result.Remove(DICOM_TAG_IMAGE_ORIENTATION_PATIENT);
+    result.Remove(DICOM_TAG_SERIES_TYPE);
+    result.Remove(DICOM_TAG_ACQUISITION_DEVICE_PROCESSING_DESCRIPTION);
+    result.Remove(DICOM_TAG_CONTRAST_BOLUS_AGENT);
+  }
+
+  void DicomMap::SetupFindInstanceTemplate(DicomMap& result)
+  {
+    SetupFindTemplate(result, INSTANCE_MAIN_DICOM_TAGS, sizeof(INSTANCE_MAIN_DICOM_TAGS) / sizeof(MainDicomTag));
+    result.SetValue(DICOM_TAG_ACCESSION_NUMBER, "", false);
+    result.SetValue(DICOM_TAG_PATIENT_ID, "", false);
+    result.SetValue(DICOM_TAG_STUDY_INSTANCE_UID, "", false);
+    result.SetValue(DICOM_TAG_SERIES_INSTANCE_UID, "", false);
+  }
+
+
+  void DicomMap::CopyTagIfExists(const DicomMap& source,
+                                 const DicomTag& tag)
+  {
+    if (source.HasTag(tag))
+    {
+      SetValue(tag, source.GetValue(tag));
+    }
+  }
+
+
+  bool DicomMap::IsMainDicomTag(const DicomTag& tag, ResourceType level)
+  {
+    const MainDicomTag *tags = NULL;
+    size_t size;
+    LoadMainDicomTags(tags, size, level);
+
+    for (size_t i = 0; i < size; i++)
+    {
+      if (tags[i].tag_ == tag)
+      {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  bool DicomMap::IsMainDicomTag(const DicomTag& tag)
+  {
+    return (IsMainDicomTag(tag, ResourceType_Patient) ||
+            IsMainDicomTag(tag, ResourceType_Study) ||
+            IsMainDicomTag(tag, ResourceType_Series) ||
+            IsMainDicomTag(tag, ResourceType_Instance));
+  }
+
+
+  void DicomMap::GetMainDicomTagsInternal(std::set<DicomTag>& result, ResourceType level)
+  {
+    const MainDicomTag *tags = NULL;
+    size_t size;
+    LoadMainDicomTags(tags, size, level);
+
+    for (size_t i = 0; i < size; i++)
+    {
+      result.insert(tags[i].tag_);
+    }
+  }
+
+
+  void DicomMap::GetMainDicomTags(std::set<DicomTag>& result, ResourceType level)
+  {
+    result.clear();
+    GetMainDicomTagsInternal(result, level);
+  }
+
+
+  void DicomMap::GetMainDicomTags(std::set<DicomTag>& result)
+  {
+    result.clear();
+    GetMainDicomTagsInternal(result, ResourceType_Patient);
+    GetMainDicomTagsInternal(result, ResourceType_Study);
+    GetMainDicomTagsInternal(result, ResourceType_Series);
+    GetMainDicomTagsInternal(result, ResourceType_Instance);
+  }
+
+
+  void DicomMap::GetTags(std::set<DicomTag>& tags) const
+  {
+    tags.clear();
+
+    for (Content::const_iterator it = content_.begin();
+         it != content_.end(); ++it)
+    {
+      tags.insert(it->first);
+    }
+  }
+
+
+  static uint16_t ReadUnsignedInteger16(const char* dicom)
+  {
+    return le16toh(*reinterpret_cast<const uint16_t*>(dicom));
+  }
+
+
+  static uint32_t ReadUnsignedInteger32(const char* dicom)
+  {
+    return le32toh(*reinterpret_cast<const uint32_t*>(dicom));
+  }
+
+
+  static bool ValidateTag(const ValueRepresentation& vr,
+                          const std::string& value)
+  {
+    switch (vr)
+    {
+      case ValueRepresentation_ApplicationEntity:
+        return value.size() <= 16;
+
+      case ValueRepresentation_AgeString:
+        return (value.size() == 4 &&
+                isdigit(value[0]) &&
+                isdigit(value[1]) &&
+                isdigit(value[2]) &&
+                (value[3] == 'D' || value[3] == 'W' || value[3] == 'M' || value[3] == 'Y'));
+
+      case ValueRepresentation_AttributeTag:
+        return value.size() == 4;
+
+      case ValueRepresentation_CodeString:
+        return value.size() <= 16;
+
+      case ValueRepresentation_Date:
+        return value.size() <= 18;
+
+      case ValueRepresentation_DecimalString:
+        return value.size() <= 16;
+
+      case ValueRepresentation_DateTime:
+        return value.size() <= 54;
+
+      case ValueRepresentation_FloatingPointSingle:
+        return value.size() == 4;
+
+      case ValueRepresentation_FloatingPointDouble:
+        return value.size() == 8;
+
+      case ValueRepresentation_IntegerString:
+        return value.size() <= 12;
+
+      case ValueRepresentation_LongString:
+        return value.size() <= 64;
+
+      case ValueRepresentation_LongText:
+        return value.size() <= 10240;
+
+      case ValueRepresentation_OtherByte:
+        return true;
+      
+      case ValueRepresentation_OtherDouble:
+        return value.size() <= (static_cast<uint64_t>(1) << 32) - 8;
+
+      case ValueRepresentation_OtherFloat:
+        return value.size() <= (static_cast<uint64_t>(1) << 32) - 4;
+
+      case ValueRepresentation_OtherLong:
+        return true;
+
+      case ValueRepresentation_OtherWord:
+        return true;
+
+      case ValueRepresentation_PersonName:
+        return true;
+
+      case ValueRepresentation_ShortString:
+        return value.size() <= 16;
+
+      case ValueRepresentation_SignedLong:
+        return value.size() == 4;
+
+      case ValueRepresentation_Sequence:
+        return true;
+
+      case ValueRepresentation_SignedShort:
+        return value.size() == 2;
+
+      case ValueRepresentation_ShortText:
+        return value.size() <= 1024;
+
+      case ValueRepresentation_Time:
+        return value.size() <= 28;
+
+      case ValueRepresentation_UnlimitedCharacters:
+        return value.size() <= (static_cast<uint64_t>(1) << 32) - 2;
+
+      case ValueRepresentation_UniqueIdentifier:
+        return value.size() <= 64;
+
+      case ValueRepresentation_UnsignedLong:
+        return value.size() == 4;
+
+      case ValueRepresentation_Unknown:
+        return true;
+
+      case ValueRepresentation_UniversalResource:
+        return value.size() <= (static_cast<uint64_t>(1) << 32) - 2;
+
+      case ValueRepresentation_UnsignedShort:
+        return value.size() == 2;
+
+      case ValueRepresentation_UnlimitedText:
+        return value.size() <= (static_cast<uint64_t>(1) << 32) - 2;
+
+      default:
+        // Assume unsupported tags are OK
+        return true;
+    }
+  }
+
+
+  static void RemoveTagPadding(std::string& value,
+                               const ValueRepresentation& vr)
+  {
+    /**
+     * Remove padding from character strings, if need be. For the time
+     * being, only the UI VR is supported.
+     * http://dicom.nema.org/medical/dicom/current/output/chtml/part05/sect_6.2.html
+     **/
+
+    switch (vr)
+    {
+      case ValueRepresentation_UniqueIdentifier:
+      {
+        /**
+         * "Values with a VR of UI shall be padded with a single
+         * trailing NULL (00H) character when necessary to achieve even
+         * length."
+         **/
+
+        if (!value.empty() &&
+            value[value.size() - 1] == '\0')
+        {
+          value.resize(value.size() - 1);
+        }
+
+        break;
+      }
+
+      /**
+       * TODO implement other VR
+       **/
+
+      default:
+        // No padding is applicable to this VR
+        break;
+    }
+  }
+
+
+  static bool ReadNextTag(DicomTag& tag,
+                          ValueRepresentation& vr,
+                          std::string& value,
+                          const char* dicom,
+                          size_t size,
+                          size_t& position)
+  {
+    /**
+     * http://dicom.nema.org/medical/dicom/current/output/chtml/part05/chapter_7.html#sect_7.1.2
+     * This function reads a data element with Explicit VR encoded using Little-Endian.
+     **/
+
+    if (position + 6 > size)
+    {
+      return false;
+    }
+
+    tag = DicomTag(ReadUnsignedInteger16(dicom + position),
+                   ReadUnsignedInteger16(dicom + position + 2));
+
+    vr = StringToValueRepresentation(std::string(dicom + position + 4, 2), true);
+    if (vr == ValueRepresentation_NotSupported)
+    {
+      return false;
+    }
+
+    if (vr == ValueRepresentation_OtherByte ||
+        vr == ValueRepresentation_OtherDouble ||
+        vr == ValueRepresentation_OtherFloat ||
+        vr == ValueRepresentation_OtherLong ||
+        vr == ValueRepresentation_OtherWord ||
+        vr == ValueRepresentation_Sequence ||
+        vr == ValueRepresentation_UnlimitedCharacters ||
+        vr == ValueRepresentation_UniversalResource ||
+        vr == ValueRepresentation_UnlimitedText ||
+        vr == ValueRepresentation_Unknown)    // Note that "UN" should never appear in the Meta Information
+    {
+      if (position + 12 > size)
+      {
+        return false;
+      }
+
+      uint32_t length = ReadUnsignedInteger32(dicom + position + 8);
+
+      if (position + 12 + length > size)
+      {
+        return false;
+      }
+
+      value.assign(dicom + position + 12, length);
+      position += (12 + length);
+    }
+    else
+    {
+      if (position + 8 > size)
+      {
+        return false;
+      }
+
+      uint16_t length = ReadUnsignedInteger16(dicom + position + 6);
+
+      if (position + 8 + length > size)
+      {
+        return false;
+      }
+
+      value.assign(dicom + position + 8, length);
+      position += (8 + length);
+    }
+
+    if (!ValidateTag(vr, value))
+    {
+      return false;
+    }
+
+    RemoveTagPadding(value, vr);
+
+    return true;
+  }
+
+
+  bool DicomMap::IsDicomFile(const void* dicom,
+                             size_t size)
+  {
+    /**
+     * http://dicom.nema.org/medical/dicom/current/output/chtml/part10/chapter_7.html
+     * According to Table 7.1-1, besides the "DICM" DICOM prefix, the
+     * file preamble (i.e. dicom[0..127]) should not be taken into
+     * account to determine whether the file is or is not a DICOM file.
+     **/
+
+    const uint8_t* p = reinterpret_cast<const uint8_t*>(dicom);
+
+    return (size >= 132 &&
+            p[128] == 'D' &&
+            p[129] == 'I' &&
+            p[130] == 'C' &&
+            p[131] == 'M');
+  }
+    
+
+  bool DicomMap::ParseDicomMetaInformation(DicomMap& result,
+                                           const void* dicom,
+                                           size_t size)
+  {
+    if (!IsDicomFile(dicom, size))
+    {
+      return false;
+    }
+
+
+    /**
+     * The DICOM File Meta Information must be encoded using the
+     * Explicit VR Little Endian Transfer Syntax
+     * (UID=1.2.840.10008.1.2.1).
+     **/
+
+    result.Clear();
+
+    // First, we read the "File Meta Information Group Length" tag
+    // (0002,0000) to know where to stop reading the meta header
+    size_t position = 132;
+
+    DicomTag tag(0x0000, 0x0000);  // Dummy initialization
+    ValueRepresentation vr;
+    std::string value;
+    if (!ReadNextTag(tag, vr, value, reinterpret_cast<const char*>(dicom), size, position) ||
+        tag.GetGroup() != 0x0002 ||
+        tag.GetElement() != 0x0000 ||
+        vr != ValueRepresentation_UnsignedLong ||
+        value.size() != 4)
+    {
+      return false;
+    }
+
+    size_t stopPosition = position + ReadUnsignedInteger32(value.c_str());
+    if (stopPosition > size)
+    {
+      return false;
+    }
+
+    while (position < stopPosition)
+    {
+      if (ReadNextTag(tag, vr, value, reinterpret_cast<const char*>(dicom), size, position))
+      {
+        result.SetValue(tag, value, IsBinaryValueRepresentation(vr));
+      }
+      else
+      {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+
+  static std::string ValueAsString(const DicomMap& summary,
+                                   const DicomTag& tag)
+  {
+    const DicomValue& value = summary.GetValue(tag);
+    if (value.IsNull())
+    {
+      return "(null)";
+    }
+    else
+    {
+      return value.GetContent();
+    }
+  }
+
+
+  void DicomMap::LogMissingTagsForStore() const
+  {
+    std::string s, t;
+
+    if (HasTag(DICOM_TAG_PATIENT_ID))
+    {
+      if (t.size() > 0)
+        t += ", ";
+      t += "PatientID=" + ValueAsString(*this, DICOM_TAG_PATIENT_ID);
+    }
+    else
+    {
+      if (s.size() > 0)
+        s += ", ";
+      s += "PatientID";
+    }
+
+    if (HasTag(DICOM_TAG_STUDY_INSTANCE_UID))
+    {
+      if (t.size() > 0)
+        t += ", ";
+      t += "StudyInstanceUID=" + ValueAsString(*this, DICOM_TAG_STUDY_INSTANCE_UID);
+    }
+    else
+    {
+      if (s.size() > 0)
+        s += ", ";
+      s += "StudyInstanceUID";
+    }
+
+    if (HasTag(DICOM_TAG_SERIES_INSTANCE_UID))
+    {
+      if (t.size() > 0)
+        t += ", ";
+      t += "SeriesInstanceUID=" + ValueAsString(*this, DICOM_TAG_SERIES_INSTANCE_UID);
+    }
+    else
+    {
+      if (s.size() > 0)
+        s += ", ";
+      s += "SeriesInstanceUID";
+    }
+
+    if (HasTag(DICOM_TAG_SOP_INSTANCE_UID))
+    {
+      if (t.size() > 0)
+        t += ", ";
+      t += "SOPInstanceUID=" + ValueAsString(*this, DICOM_TAG_SOP_INSTANCE_UID);
+    }
+    else
+    {
+      if (s.size() > 0)
+        s += ", ";
+      s += "SOPInstanceUID";
+    }
+
+    if (t.size() == 0)
+    {
+      LOG(ERROR) << "Store has failed because all the required tags (" << s << ") are missing (is it a DICOMDIR file?)";
+    }
+    else
+    {
+      LOG(ERROR) << "Store has failed because required tags (" << s << ") are missing for the following instance: " << t;
+    }
+  }
+
+
+  bool DicomMap::LookupStringValue(std::string& result,
+                                   const DicomTag& tag,
+                                   bool allowBinary) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->CopyToString(result, allowBinary);
+    }
+  }
+    
+  bool DicomMap::ParseInteger32(int32_t& result,
+                                const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->ParseInteger32(result);
+    }
+  }
+
+  bool DicomMap::ParseInteger64(int64_t& result,
+                                const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->ParseInteger64(result);
+    }
+  }
+
+  bool DicomMap::ParseUnsignedInteger32(uint32_t& result,
+                                        const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->ParseUnsignedInteger32(result);
+    }
+  }
+
+  bool DicomMap::ParseUnsignedInteger64(uint64_t& result,
+                                        const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->ParseUnsignedInteger64(result);
+    }
+  }
+
+  bool DicomMap::ParseFloat(float& result,
+                            const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->ParseFloat(result);
+    }
+  }
+
+  bool DicomMap::ParseFirstFloat(float& result,
+                                 const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->ParseFirstFloat(result);
+    }
+  }
+
+  bool DicomMap::ParseDouble(double& result,
+                             const DicomTag& tag) const
+  {
+    const DicomValue* value = TestAndGetValue(tag);
+
+    if (value == NULL)
+    {
+      return false;
+    }
+    else
+    {
+      return value->ParseDouble(result);
+    }
+  }
+
+  
+  void DicomMap::FromDicomAsJson(const Json::Value& dicomAsJson)
+  {
+    if (dicomAsJson.type() != Json::objectValue)
+    {
+      throw OrthancException(ErrorCode_BadFileFormat);
+    }
+    
+    Clear();
+    
+    Json::Value::Members tags = dicomAsJson.getMemberNames();
+    for (Json::Value::Members::const_iterator
+           it = tags.begin(); it != tags.end(); ++it)
+    {
+      DicomTag tag(0, 0);
+      if (!DicomTag::ParseHexadecimal(tag, it->c_str()))
+      {
+        throw OrthancException(ErrorCode_CorruptedFile);
+      }
+
+      const Json::Value& value = dicomAsJson[*it];
+
+      if (value.type() != Json::objectValue ||
+          !value.isMember("Type") ||
+          !value.isMember("Value") ||
+          value["Type"].type() != Json::stringValue)
+      {
+        throw OrthancException(ErrorCode_CorruptedFile);
+      }
+
+      if (value["Type"] == "String")
+      {
+        if (value["Value"].type() != Json::stringValue)
+        {
+          throw OrthancException(ErrorCode_CorruptedFile);
+        }
+        else
+        {
+          SetValue(tag, value["Value"].asString(), false /* not binary */);
+        }
+      }
+    }
+  }
+
+
+  void DicomMap::Merge(const DicomMap& other)
+  {
+    for (Content::const_iterator it = other.content_.begin();
+         it != other.content_.end(); ++it)
+    {
+      assert(it->second != NULL);
+
+      if (content_.find(it->first) == content_.end())
+      {
+        content_[it->first] = it->second->Clone();
+      }
+    }
+  }
+
+
+  void DicomMap::MergeMainDicomTags(const DicomMap& other,
+                                    ResourceType level)
+  {
+    const MainDicomTag* tags = NULL;
+    size_t size = 0;
+
+    LoadMainDicomTags(tags, size, level);
+    assert(tags != NULL && size > 0);
+
+    for (size_t i = 0; i < size; i++)
+    {
+      Content::const_iterator found = other.content_.find(tags[i].tag_);
+
+      if (found != other.content_.end() &&
+          content_.find(tags[i].tag_) == content_.end())
+      {
+        assert(found->second != NULL);
+        content_[tags[i].tag_] = found->second->Clone();
+      }
+    }
+  }
+    
+
+  void DicomMap::ExtractMainDicomTags(const DicomMap& other)
+  {
+    Clear();
+    MergeMainDicomTags(other, ResourceType_Patient);
+    MergeMainDicomTags(other, ResourceType_Study);
+    MergeMainDicomTags(other, ResourceType_Series);
+    MergeMainDicomTags(other, ResourceType_Instance);
+  }    
+
+
+  bool DicomMap::HasOnlyMainDicomTags() const
+  {
+    // TODO - Speed up possible by making this std::set a global variable
+
+    std::set<DicomTag> mainDicomTags;
+    GetMainDicomTags(mainDicomTags);
+
+    for (Content::const_iterator it = content_.begin(); it != content_.end(); ++it)
+    {
+      if (mainDicomTags.find(it->first) == mainDicomTags.end())
+      {
+        return false;
+      }
+    }
+
+    return true;
+  }
+    
+
+  void DicomMap::Serialize(Json::Value& target) const
+  {
+    target = Json::objectValue;
+
+    for (Content::const_iterator it = content_.begin(); it != content_.end(); ++it)
+    {
+      assert(it->second != NULL);
+      
+      std::string tag = it->first.Format();
+
+      Json::Value value;
+      it->second->Serialize(value);
+
+      target[tag] = value;
+    }
+  }
+  
+
+  void DicomMap::Unserialize(const Json::Value& source)
+  {
+    Clear();
+
+    if (source.type() != Json::objectValue)
+    {
+      throw OrthancException(ErrorCode_BadFileFormat);
+    }
+
+    Json::Value::Members tags = source.getMemberNames();
+
+    for (size_t i = 0; i < tags.size(); i++)
+    {
+      DicomTag tag(0, 0);
+      
+      if (!DicomTag::ParseHexadecimal(tag, tags[i].c_str()) ||
+          content_.find(tag) != content_.end())
+      {
+        throw OrthancException(ErrorCode_BadFileFormat);
+      }
+
+      std::unique_ptr<DicomValue> value(new DicomValue);
+      value->Unserialize(source[tags[i]]);
+
+      content_[tag] = value.release();
+    }
+  }
+
+
+  void DicomMap::FromDicomWeb(const Json::Value& source)
+  {
+    static const char* const ALPHABETIC = "Alphabetic";
+    static const char* const IDEOGRAPHIC = "Ideographic";
+    static const char* const INLINE_BINARY = "InlineBinary";
+    static const char* const PHONETIC = "Phonetic";
+    static const char* const VALUE = "Value";
+    static const char* const VR = "vr";
+  
+    Clear();
+
+    if (source.type() != Json::objectValue)
+    {
+      throw OrthancException(ErrorCode_BadFileFormat);
+    }
+  
+    Json::Value::Members tags = source.getMemberNames();
+
+    for (size_t i = 0; i < tags.size(); i++)
+    {
+      const Json::Value& item = source[tags[i]];
+      DicomTag tag(0, 0);
+
+      if (item.type() != Json::objectValue ||
+          !item.isMember(VR) ||
+          item[VR].type() != Json::stringValue ||
+          !DicomTag::ParseHexadecimal(tag, tags[i].c_str()))
+      {
+        throw OrthancException(ErrorCode_BadFileFormat);
+      }
+
+      ValueRepresentation vr = StringToValueRepresentation(item[VR].asString(), false);
+
+      if (item.isMember(INLINE_BINARY))
+      {
+        const Json::Value& value = item[INLINE_BINARY];
+
+        if (value.type() == Json::stringValue)
+        {
+          std::string decoded;
+          Toolbox::DecodeBase64(decoded, value.asString());
+          SetValue(tag, decoded, true /* binary data */);
+        }
+      }
+      else if (!item.isMember(VALUE))
+      {
+        // Tag is present, but it has a null value
+        SetValue(tag, "", false /* not binary */);
+      }
+      else
+      {
+        const Json::Value& value = item[VALUE];
+
+        if (value.type() == Json::arrayValue)
+        {
+          bool supported = true;
+          
+          std::string s;
+          for (Json::Value::ArrayIndex i = 0; i < value.size() && supported; i++)
+          {
+            if (!s.empty())
+            {
+              s += '\\';
+            }
+
+            switch (value[i].type())
+            {
+              case Json::objectValue:
+                if (vr == ValueRepresentation_PersonName &&
+                    value[i].type() == Json::objectValue)
+                {
+                  if (value[i].isMember(ALPHABETIC) &&
+                      value[i][ALPHABETIC].type() == Json::stringValue)
+                  {
+                    s += value[i][ALPHABETIC].asString();
+                  }
+
+                  bool hasIdeographic = false;
+                  
+                  if (value[i].isMember(IDEOGRAPHIC) &&
+                      value[i][IDEOGRAPHIC].type() == Json::stringValue)
+                  {
+                    s += '=' + value[i][IDEOGRAPHIC].asString();
+                    hasIdeographic = true;
+                  }
+                  
+                  if (value[i].isMember(PHONETIC) &&
+                      value[i][PHONETIC].type() == Json::stringValue)
+                  {
+                    if (!hasIdeographic)
+                    {
+                      s += '=';
+                    }
+                      
+                    s += '=' + value[i][PHONETIC].asString();
+                  }
+                }
+                else
+                {
+                  // This is the case of sequences
+                  supported = false;
+                }
+
+                break;
+            
+              case Json::stringValue:
+                s += value[i].asString();
+                break;
+              
+              case Json::intValue:
+                s += boost::lexical_cast<std::string>(value[i].asInt());
+                break;
+              
+              case Json::uintValue:
+                s += boost::lexical_cast<std::string>(value[i].asUInt());
+                break;
+              
+              case Json::realValue:
+                s += boost::lexical_cast<std::string>(value[i].asDouble());
+                break;
+              
+              default:
+                break;
+            }
+          }
+
+          if (supported)
+          {
+            SetValue(tag, s, false /* not binary */);
+          }
+        }
+      }
+    }
+  }
+
+
+  std::string DicomMap::GetStringValue(const DicomTag& tag,
+                                       const std::string& defaultValue,
+                                       bool allowBinary) const
+  {
+    std::string s;
+    if (LookupStringValue(s, tag, allowBinary))
+    {
+      return s;
+    }
+    else
+    {
+      return defaultValue;
+    }
+  }
+
+
+  void DicomMap::RemoveBinaryTags()
+  {
+    Content kept;
+
+    for (Content::iterator it = content_.begin(); it != content_.end(); ++it)
+    {
+      assert(it->second != NULL);
+
+      if (!it->second->IsBinary() &&
+          !it->second->IsNull())
+      {
+        kept[it->first] = it->second;
+      }
+      else
+      {
+        delete it->second;
+      }
+    }
+
+    content_ = kept;
+  }
+
+
+  void DicomMap::DumpMainDicomTags(Json::Value& target,
+                                   ResourceType level) const
+  {
+    std::map<DicomTag, std::string> mainTags;   // TODO - Create a singleton to hold this map
+    LoadMainDicomTags(mainTags, level);
+    
+    target = Json::objectValue;
+
+    for (Content::const_iterator it = content_.begin(); it != content_.end(); ++it)
+    {
+      assert(it->second != NULL);
+      
+      if (!it->second->IsBinary() &&
+          !it->second->IsNull())
+      {
+        std::map<DicomTag, std::string>::const_iterator found = mainTags.find(it->first);
+
+        if (found != mainTags.end())
+        {
+          target[found->second] = it->second->GetContent();
+        }
+      }
+    }    
+  }
+  
+
+  void DicomMap::ParseMainDicomTags(const Json::Value& source,
+                                    ResourceType level)
+  {
+    if (source.type() != Json::objectValue)
+    {
+      throw OrthancException(ErrorCode_BadFileFormat);
+    }
+    
+    std::map<std::string, DicomTag2> mainTags;   // TODO - Create a singleton to hold this map
+    LoadMainDicomTags(mainTags, level);
+    
+    Json::Value::Members members = source.getMemberNames();
+    for (size_t i = 0; i < members.size(); i++)
+    {
+      std::map<std::string, DicomTag2>::const_iterator found = mainTags.find(members[i]);
+
+      if (found != mainTags.end())
+      {
+        const Json::Value& value = source[members[i]];
+        if (value.type() != Json::stringValue)
+        {
+          throw OrthancException(ErrorCode_BadFileFormat);
+        }
+        else
+        {
+          SetValue(found->second, value.asString(), false);
+        }
+      }
+    }
+  }
+
+
+  void DicomMap::Print(FILE* fp) const
+  {
+    DicomArray a(*this);
+    a.Print(fp);
+  }
+}