diff --git a/dumux/io/rasterimagedata.hh b/dumux/io/rasterimagedata.hh
new file mode 100644
index 0000000000000000000000000000000000000000..b8b9a0ffea12fde112156938ef3339d4e623d238
--- /dev/null
+++ b/dumux/io/rasterimagedata.hh
@@ -0,0 +1,96 @@
+// -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+// vi: set et ts=4 sw=4 sts=4:
+/*****************************************************************************
+ *   See the file COPYING for full copying permissions.                      *
+ *                                                                           *
+ *   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.                                     *
+ *                                                                           *
+ *   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/>.   *
+ *****************************************************************************/
+/*!
+ * \file
+ * \ingroup InputOutput
+ * \brief  A data class for raster image information
+ */
+#ifndef DUMUX_RASTER_IMAGE_DATA_HH
+#define DUMUX_RASTER_IMAGE_DATA_HH
+
+#include <string>
+#include <vector>
+#include <fstream>
+
+namespace Dumux::Detail::RasterImageData {
+
+/*!
+    * \brief A struct that holds all information of the image format.
+    */
+struct Format
+{
+    std::string magicNumber;
+    std::string type;
+    std::string encoding;
+};
+
+/*!
+    * \brief A struct that contains all header data of the image.
+    */
+struct HeaderData
+{
+    Format format;
+    std::size_t nCols;
+    std::size_t nRows;
+    std::size_t maxValue = 1;
+};
+
+/*!
+    * \brief The return type of the reading functions.
+    *        Holds the actual pixel values and the header data.
+    */
+template<class T>
+class Result : private std::vector<T>
+{
+    using Parent = std::vector<T>;
+public:
+    Result() = delete;
+
+    /*!
+        * \brief Construct from data and header by copy
+        */
+    Result(const std::vector<T>& data, const HeaderData& header)
+    : Parent(data)
+    , header_(header)
+    {}
+
+    /*!
+        * \brief Construct from data and header by move
+        */
+    Result(std::vector<T>&& data, HeaderData&& header)
+    : Parent(std::move(data))
+    , header_(std::move(header))
+    {}
+
+    //! Returns the header data.
+    const HeaderData& header() const { return header_; }
+
+    // expose some methods of std::vector
+    using Parent::operator[];
+    using Parent::begin;
+    using Parent::end;
+    using Parent::size;
+
+private:
+    HeaderData header_;
+};
+
+} // end namespace Dumux::Detail::RasterImageData
+
+#endif
diff --git a/dumux/io/rasterimagereader.hh b/dumux/io/rasterimagereader.hh
index 341a14bfa434de1bfc4a675c4fef94121209418b..038377f3bfb952651d4b092e693541f03eba0017 100644
--- a/dumux/io/rasterimagereader.hh
+++ b/dumux/io/rasterimagereader.hh
@@ -36,6 +36,7 @@
 
 #include <dune/common/exceptions.hh>
 #include <dumux/common/stringutilities.hh>
+#include <dumux/io/rasterimagedata.hh>
 
 namespace Dumux {
 
@@ -46,67 +47,13 @@ namespace Dumux {
  */
 class NetPBMReader
 {
-public:
-    /*!
-     * \brief A struct that holds all information of the image format.
-     */
-    struct Format
-    {
-        std::string magicNumber;
-        std::string type;
-        std::string encoding;
-    };
+    template<typename T>
+    using Result = Detail::RasterImageData::Result<T>;
 
-    /*!
-     * \brief A struct that contains all header data of the image.
-     */
-    struct HeaderData
-    {
-        Format format;
-        std::size_t nCols;
-        std::size_t nRows;
-        std::size_t maxValue = 1;
-    };
+    using HeaderData = Detail::RasterImageData::HeaderData;
+    using Format = Detail::RasterImageData::Format;
 
-    /*!
-     * \brief The return type of the reading functions.
-     *        Holds the actual pixel values and the header data.
-     */
-    template<class T>
-    class Result : private std::vector<T>
-    {
-        using Parent = std::vector<T>;
-    public:
-        Result() = delete;
-
-        /*!
-         * \brief Construct from data and header by copy
-         */
-        Result(const std::vector<T>& data, const HeaderData& header)
-        : Parent(data)
-        , header_(header)
-        {}
-
-        /*!
-         * \brief Construct from data and header by move
-         */
-        Result(std::vector<T>&& data, HeaderData&& header)
-        : Parent(std::move(data))
-        , header_(std::move(header))
-        {}
-
-        //! Returns the header data.
-        const HeaderData& header() const { return header_; }
-
-        // expose some methods of std::vector
-        using Parent::operator[];
-        using Parent::begin;
-        using Parent::end;
-        using Parent::size;
-
-    private:
-        HeaderData header_;
-    };
+public:
 
     /*!
      * \brief A helper function to retrieve the format from tokens of the file's first line.