diff --git a/include/qpdf/QPDFObjectHandle.hh b/include/qpdf/QPDFObjectHandle.hh
index 77fe680f..b722b083 100644
--- a/include/qpdf/QPDFObjectHandle.hh
+++ b/include/qpdf/QPDFObjectHandle.hh
@@ -1497,6 +1497,7 @@ class QPDFObjectHandle
         friend class QPDF_Dictionary;
         friend class QPDF_Stream;
         friend class SparseOHArray;
+        friend class OHArray;
 
       private:
         static void
diff --git a/libqpdf/CMakeLists.txt b/libqpdf/CMakeLists.txt
index 5e3a628e..2d857f45 100644
--- a/libqpdf/CMakeLists.txt
+++ b/libqpdf/CMakeLists.txt
@@ -116,6 +116,7 @@ set(libqpdf_SOURCES
   SecureRandomDataProvider.cc
   SF_FlateLzwDecode.cc
   SparseOHArray.cc
+  OHArray.cc
   qpdf-c.cc
   qpdfjob-c.cc
   qpdflogger-c.cc)
diff --git a/libqpdf/OHArray.cc b/libqpdf/OHArray.cc
new file mode 100644
index 00000000..436fa4f2
--- /dev/null
+++ b/libqpdf/OHArray.cc
@@ -0,0 +1,148 @@
+#include <qpdf/OHArray.hh>
+
+#include <qpdf/QPDFObjectHandle.hh>
+#include <qpdf/QPDFObject_private.hh>
+
+#include <stdexcept>
+
+OHArray::OHArray() :
+    n_elements(0)
+{
+}
+
+size_t
+OHArray::size() const
+{
+    return this->n_elements;
+}
+
+void
+OHArray::append(QPDFObjectHandle oh)
+{
+    if (!oh.isDirectNull()) {
+        this->elements[this->n_elements] = oh;
+    }
+    ++this->n_elements;
+}
+
+void
+OHArray::append(std::shared_ptr<QPDFObject>&& obj)
+{
+    if (obj->getTypeCode() != ::ot_null || !obj->getObjGen().isIndirect()) {
+        this->elements[this->n_elements] = std::move(obj);
+    }
+    ++this->n_elements;
+}
+
+QPDFObjectHandle
+OHArray::at(size_t idx) const
+{
+    if (idx >= this->n_elements) {
+        throw std::logic_error(
+            "INTERNAL ERROR: bounds error accessing OHArray element");
+    }
+    auto const& iter = this->elements.find(idx);
+    if (iter == this->elements.end()) {
+        return QPDFObjectHandle::newNull();
+    } else {
+        return (*iter).second;
+    }
+}
+
+void
+OHArray::remove_last()
+{
+    if (this->n_elements == 0) {
+        throw std::logic_error("INTERNAL ERROR: attempt to remove"
+                               " last item from empty OHArray");
+    }
+    --this->n_elements;
+    this->elements.erase(this->n_elements);
+}
+
+void
+OHArray::disconnect()
+{
+    for (auto& iter: this->elements) {
+        QPDFObjectHandle::DisconnectAccess::disconnect(iter.second);
+    }
+}
+
+void
+OHArray::setAt(size_t idx, QPDFObjectHandle oh)
+{
+    if (idx >= this->n_elements) {
+        throw std::logic_error("bounds error setting item in OHArray");
+    }
+    if (oh.isDirectNull()) {
+        this->elements.erase(idx);
+    } else {
+        this->elements[idx] = oh;
+    }
+}
+
+void
+OHArray::erase(size_t idx)
+{
+    if (idx >= this->n_elements) {
+        throw std::logic_error("bounds error erasing item from OHArray");
+    }
+    decltype(this->elements) dest;
+    for (auto const& iter: this->elements) {
+        if (iter.first < idx) {
+            dest.insert(iter);
+        } else if (iter.first > idx) {
+            dest[iter.first - 1] = iter.second;
+        }
+    }
+    this->elements = dest;
+    --this->n_elements;
+}
+
+void
+OHArray::insert(size_t idx, QPDFObjectHandle oh)
+{
+    if (idx > this->n_elements) {
+        throw std::logic_error("bounds error inserting item to OHArray");
+    } else if (idx == this->n_elements) {
+        // Allow inserting to the last position
+        append(oh);
+    } else {
+        decltype(this->elements) dest;
+        for (auto const& iter: this->elements) {
+            if (iter.first < idx) {
+                dest.insert(iter);
+            } else {
+                dest[iter.first + 1] = iter.second;
+            }
+        }
+        this->elements = dest;
+        this->elements[idx] = oh;
+        ++this->n_elements;
+    }
+}
+
+OHArray
+OHArray::copy()
+{
+    OHArray result;
+    result.n_elements = this->n_elements;
+    for (auto const& element: this->elements) {
+        auto value = element.second;
+        result.elements[element.first] =
+            value.isIndirect() ? value : value.shallowCopy();
+    }
+    return result;
+}
+
+OHArray::const_iterator
+OHArray::begin() const
+{
+    return this->elements.begin();
+}
+
+OHArray::const_iterator
+OHArray::end() const
+{
+    return this->elements.end();
+}
diff --git a/libqpdf/QPDF_Array.cc b/libqpdf/QPDF_Array.cc
index 93fbf928..ed43245f 100644
--- a/libqpdf/QPDF_Array.cc
+++ b/libqpdf/QPDF_Array.cc
@@ -19,6 +19,13 @@ QPDF_Array::QPDF_Array(std::vector<std::shared_ptr<QPDFObject>>&& v) :
 
 QPDF_Array::QPDF_Array(SparseOHArray const& items) :
     QPDFValue(::ot_array, "array"),
+    sp_elements(items)
+{
+}
+
+QPDF_Array::QPDF_Array(OHArray const& items) :
+    QPDFValue(::ot_array, "array"),
+    sparse(false),
     elements(items)
 {
 }
@@ -41,93 +48,168 @@ QPDF_Array::create(SparseOHArray const& items)
     return do_create(new QPDF_Array(items));
 }
 
+std::shared_ptr<QPDFObject>
+QPDF_Array::create(OHArray const& items)
+{
+    return do_create(new QPDF_Array(items));
+}
+
 std::shared_ptr<QPDFObject>
 QPDF_Array::copy(bool shallow)
 {
-    return create(shallow ? elements : elements.copy());
+    if (sparse) {
+        return create(shallow ? sp_elements : sp_elements.copy());
+    } else {
+        return create(shallow ? elements : elements.copy());
+    }
 }
 
 void
 QPDF_Array::disconnect()
 {
-    elements.disconnect();
+    if (sparse) {
+        sp_elements.disconnect();
+    } else {
+        elements.disconnect();
+    }
 }
 
 std::string
 QPDF_Array::unparse()
 {
-    std::string result = "[ ";
-    size_t size = this->elements.size();
-    for (size_t i = 0; i < size; ++i) {
-        result += this->elements.at(i).unparse();
-        result += " ";
+    if (sparse) {
+        std::string result = "[ ";
+        size_t size = sp_elements.size();
+        for (size_t i = 0; i < size; ++i) {
+            result += sp_elements.at(i).unparse();
+            result += " ";
+        }
+        result += "]";
+        return result;
+    } else {
+        std::string result = "[ ";
+        size_t size = elements.size();
+        for (size_t i = 0; i < size; ++i) {
+            result += elements.at(i).unparse();
+            result += " ";
+        }
+        result += "]";
+        return result;
     }
-    result += "]";
-    return result;
 }
 
 JSON
 QPDF_Array::getJSON(int json_version)
 {
-    JSON j = JSON::makeArray();
-    size_t size = this->elements.size();
-    for (size_t i = 0; i < size; ++i) {
-        j.addArrayElement(this->elements.at(i).getJSON(json_version));
+    if (sparse) {
+        JSON j = JSON::makeArray();
+        size_t size = sp_elements.size();
+        for (size_t i = 0; i < size; ++i) {
+            j.addArrayElement(sp_elements.at(i).getJSON(json_version));
+        }
+        return j;
+    } else {
+        JSON j = JSON::makeArray();
+        size_t size = elements.size();
+        for (size_t i = 0; i < size; ++i) {
+            j.addArrayElement(elements.at(i).getJSON(json_version));
+        }
+        return j;
     }
-    return j;
 }
 
 int
 QPDF_Array::getNItems() const
 {
-    // This should really return a size_t, but changing it would break
-    // a lot of code.
-    return QIntC::to_int(this->elements.size());
+    if (sparse) {
+        // This should really return a size_t, but changing it would break
+        // a lot of code.
+        return QIntC::to_int(sp_elements.size());
+    } else {
+        return QIntC::to_int(elements.size());
+    }
 }
 
 QPDFObjectHandle
 QPDF_Array::getItem(int n) const
 {
-    if ((n < 0) || (n >= QIntC::to_int(elements.size()))) {
-        throw std::logic_error(
-            "INTERNAL ERROR: bounds error accessing QPDF_Array element");
+    if (sparse) {
+        if ((n < 0) || (n >= QIntC::to_int(sp_elements.size()))) {
+            throw std::logic_error(
+                "INTERNAL ERROR: bounds error accessing QPDF_Array element");
+        }
+        return sp_elements.at(QIntC::to_size(n));
+    } else {
+        if ((n < 0) || (n >= QIntC::to_int(elements.size()))) {
+            throw std::logic_error(
+                "INTERNAL ERROR: bounds error accessing QPDF_Array element");
+        }
+        return elements.at(QIntC::to_size(n));
     }
-    return this->elements.at(QIntC::to_size(n));
 }
 
 void
 QPDF_Array::getAsVector(std::vector<QPDFObjectHandle>& v) const
 {
-    size_t size = this->elements.size();
-    for (size_t i = 0; i < size; ++i) {
-        v.push_back(this->elements.at(i));
+    if (sparse) {
+        size_t size = sp_elements.size();
+        for (size_t i = 0; i < size; ++i) {
+            v.push_back(sp_elements.at(i));
+        }
+    } else {
+        size_t size = elements.size();
+        for (size_t i = 0; i < size; ++i) {
+            v.push_back(elements.at(i));
+        }
     }
 }
 
 void
 QPDF_Array::setItem(int n, QPDFObjectHandle const& oh)
 {
-    this->elements.setAt(QIntC::to_size(n), oh);
+    if (sparse) {
+        sp_elements.setAt(QIntC::to_size(n), oh);
+    } else {
+        elements.setAt(QIntC::to_size(n), oh);
+    }
 }
 
 void
 QPDF_Array::setFromVector(std::vector<QPDFObjectHandle> const& v)
 {
-    this->elements = SparseOHArray();
-    for (auto const& iter: v) {
-        this->elements.append(iter);
+    if (sparse) {
+        sp_elements = SparseOHArray();
+        for (auto const& iter: v) {
+            sp_elements.append(iter);
+        }
+    } else {
+        elements = OHArray();
+        for (auto const& iter: v) {
+            elements.append(iter);
+        }
     }
 }
 
 void
 QPDF_Array::setFromVector(std::vector<std::shared_ptr<QPDFObject>>&& v)
 {
-    this->elements = SparseOHArray();
-    for (auto&& item: v) {
-        if (item) {
-            this->elements.append(item);
-        } else {
-            ++this->elements.n_elements;
+    if (sparse) {
+        sp_elements = SparseOHArray();
+        for (auto&& item: v) {
+            if (item) {
+                sp_elements.append(item);
+            } else {
+                ++sp_elements.n_elements;
+            }
+        }
+    } else {
+        elements = OHArray();
+        for (auto&& item: v) {
+            if (item) {
+                elements.append(item);
+            } else {
+                ++elements.n_elements;
+            }
         }
     }
 }
@@ -135,22 +217,39 @@ QPDF_Array::setFromVector(std::vector<std::shared_ptr<QPDFObject>>&& v)
 void
 QPDF_Array::insertItem(int at, QPDFObjectHandle const& item)
 {
-    // As special case, also allow insert beyond the end
-    if ((at < 0) || (at > QIntC::to_int(this->elements.size()))) {
-        throw std::logic_error(
-            "INTERNAL ERROR: bounds error accessing QPDF_Array element");
+    if (sparse) {
+        // As special case, also allow insert beyond the end
+        if ((at < 0) || (at > QIntC::to_int(sp_elements.size()))) {
+            throw std::logic_error(
+                "INTERNAL ERROR: bounds error accessing QPDF_Array element");
+        }
+        sp_elements.insert(QIntC::to_size(at), item);
+    } else {
+        // As special case, also allow insert beyond the end
+        if ((at < 0) || (at > QIntC::to_int(elements.size()))) {
+            throw std::logic_error(
+                "INTERNAL ERROR: bounds error accessing QPDF_Array element");
+        }
+        elements.insert(QIntC::to_size(at), item);
     }
-    this->elements.insert(QIntC::to_size(at), item);
 }
 
 void
 QPDF_Array::appendItem(QPDFObjectHandle const& item)
 {
-    this->elements.append(item);
+    if (sparse) {
+        sp_elements.append(item);
+    } else {
+        elements.append(item);
+    }
 }
 
 void
 QPDF_Array::eraseItem(int at)
 {
-    this->elements.erase(QIntC::to_size(at));
+    if (sparse) {
+        sp_elements.erase(QIntC::to_size(at));
+    } else {
+        elements.erase(QIntC::to_size(at));
+    }
 }
diff --git a/libqpdf/qpdf/OHArray.hh b/libqpdf/qpdf/OHArray.hh
new file mode 100644
index 00000000..66223c4f
--- /dev/null
+++ b/libqpdf/qpdf/OHArray.hh
@@ -0,0 +1,35 @@
+#ifndef QPDF_OHARRAY_HH
+#define QPDF_OHARRAY_HH
+
+#include <qpdf/QPDFObjectHandle.hh>
+#include <unordered_map>
+
+class QPDF_Array;
+
+class OHArray
+{
+  public:
+    OHArray();
+    size_t size() const;
+    void append(QPDFObjectHandle oh);
+    void append(std::shared_ptr<QPDFObject>&& obj);
+    QPDFObjectHandle at(size_t idx) const;
+    void remove_last();
+    void setAt(size_t idx, QPDFObjectHandle oh);
+    void erase(size_t idx);
+    void insert(size_t idx, QPDFObjectHandle oh);
+    OHArray copy();
+    void disconnect();
+
+    typedef std::unordered_map<size_t, QPDFObjectHandle>::const_iterator
+        const_iterator;
+    const_iterator begin() const;
+    const_iterator end() const;
+
+  private:
+    friend class QPDF_Array;
+    std::unordered_map<size_t, QPDFObjectHandle> elements;
+    size_t n_elements;
+};
+
+#endif // QPDF_OHARRAY_HH
diff --git a/libqpdf/qpdf/QPDF_Array.hh b/libqpdf/qpdf/QPDF_Array.hh
index 88397ba7..1c4227ba 100644
--- a/libqpdf/qpdf/QPDF_Array.hh
+++ b/libqpdf/qpdf/QPDF_Array.hh
@@ -3,6 +3,7 @@
 
 #include <qpdf/QPDFValue.hh>
 
+#include <qpdf/OHArray.hh>
 #include <qpdf/SparseOHArray.hh>
 #include <list>
 #include <vector>
@@ -16,6 +17,7 @@ class QPDF_Array: public QPDFValue
     static std::shared_ptr<QPDFObject>
     create(std::vector<std::shared_ptr<QPDFObject>>&& items);
     static std::shared_ptr<QPDFObject> create(SparseOHArray const& items);
+    static std::shared_ptr<QPDFObject> create(OHArray const& items);
     virtual std::shared_ptr<QPDFObject> copy(bool shallow = false);
     virtual std::string unparse();
     virtual JSON getJSON(int json_version);
@@ -36,7 +38,10 @@ class QPDF_Array: public QPDFValue
     QPDF_Array(std::vector<QPDFObjectHandle> const& items);
     QPDF_Array(std::vector<std::shared_ptr<QPDFObject>>&& items);
     QPDF_Array(SparseOHArray const& items);
-    SparseOHArray elements;
+    QPDF_Array(OHArray const& items);
+    bool sparse{false};
+    SparseOHArray sp_elements;
+    OHArray elements;
 };
 
 #endif // QPDF_ARRAY_HH