MASTER THESIS Video Watermarking - Computer Graphics Group ...

Appendix C
Programming Documentation
There is the programming documentation, generated from the source code of
the plugin, on the enclosed CD but lacks description of adding another
watermarking method.
In order to add a new watermarking method into the watermarking
framework, several actions have to be taken:
The identifier of the method has to be inserted into the list of available
methods. The list, named WatermarkMethod, is located in file watermark.h.
The name and the description of the method have to be inserted into the list of
possible values of the plugin's parameter method. The list is located in file
gsth264watermark.c and its name is mode_types.
Both embedding and detection functions have to be implemented. The file that
contains the functions should be listed in file Makefile.am and the header
file with the function declarations should be included in file watermark.c.
The embedding and the detection functions have to be specified as the second
and the third item in the defining structure in the list of defining structures.
The list, named methods, is located in file watermark.c. The first item of
the structure is the type of watermarking domain that the method uses; it is
either WATERMARK_DOMAIN_FREQUENCY or WATERMARK_DOMAIN_SPATIAL.
Both the embedding and the detection functions in frequency domain have
the same arguments in the following order:
watermark is pointer to the framework context.
coefficients is pointer to the list of transform coefficients of one block. The
list contains zig-zag scan of the coefficients in case of frame macroblocks, or
field scan in case of field macroblocks.
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