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@@ -53,3 +53,89 @@ Note that _ImageFile_ attemtps to determine the file format by looking at the fi
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Supported file formats include PGM/PPM out of the box and those provided by libpng, libjpeg and libimagemagick++.
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The sample images do not need any additional libraries.
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+
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+# Sample code
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+There is a complete sample program for every tutorial in this series.
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+These samples are built along with NICE and can be found in the
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+__core__ output directory.
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+
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+The sample program for this tutorial reads a file from disk to memory,
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+displays metadata from the file header and writes the image to another
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+file.
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+
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+You can find PXM sample images to use with the sample code
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+in the __tutorial__ folder.
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+
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+## Includes
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+We start of the sample program by including the necessary header files.
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+The first few tutorials explain the usage of classes in the __image__
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+subdirectory.
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+
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+Header files are usually named after the classes they declare.
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+We need the _ImageT_ and _ImageFile_ classes, so our sample code
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+starts like this:
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+
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+```c++
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+#include <iostream>
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+#include <string>
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+#include <core/image/ImageT.h>
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+#include <core/image/ImageFile.h>
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+```
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+
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+## File names
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+We then get the file names from the command line.
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+NICE will automatically determine the file type from its ending.
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+This works for reads and writes, so you can use this sample program
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+as a simple converter between image formats.
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+
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+This next part simply checks if the user specified both source and
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+destination file.
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+If there are enough arguments, they are stored in a _string_.
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+
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+```c++
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+// Check if enough parameters were supplied
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+if (argc < 3) {
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+ std::cout << "USAGE: " << argv[0] << " <input image> <output image>\n";
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+ return -1;
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+}
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+
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+// These are our file names
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+std::string input_path(argv[1]);
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+std::string output_path(argv[2]);
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+```
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+
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+## Image metadata
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+_ImageFile_ can read the header information without reading the whole image
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+into memory.
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+We use the __getHeader__ method to obtain a _Header_ instance.
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+The fields are written to the standard output.
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+
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+```c++
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+// Read file header and display header information
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+NICE::ImageFile source_file(input_path);
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+NICE::ImageFile::Header source_header = source_file.getHeader();
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+
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+std::cout << "Source image dimensions: " << source_header.width << " x " << source_header.height;
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+std::cout << " (" << source_header.channel << " channels, " << source_header.bitdepth << " bpp)\n";
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+```
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+
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+## Reading and writing the image
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+To read the image, we create an empty instance of _ColorImage_ hand it over
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+to the file's __reader__ method.
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+
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+Writing the image to disk is just as easy: contruct an _ImageFile_ with the
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+destination path and call the __writer__ method.
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+
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+```c++
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+// Read image into memory
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+NICE::ColorImage source_image;
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+source_file.reader(&source_image);
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+
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+// Write image to disk
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+NICE::ImageFile dest_image(output_path);
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+dest_image.writer(&source_image);
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+return 0;
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+```
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+
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+Remember that _ImageFile_ objects are just containers for a file's location
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+and only open the file when you call methods that require reading or writing.
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Clemens-Alexander Brust