MASTER THESIS Video Watermarking - Computer Graphics Group ...

Table 1 outlines characteristics of the sequences.
Table 1: Characteristics of testing video sequences
Each test script embeds a watermark into each testing video sequence using
each proposed watermarking method – block, coefficient or noise – with weight
factor from 1 to 5, applies the test itself and obtains the result.
Watermarks are generated with content ID assigned to the sequences
subsequently from 1 to 7. If not mentioned otherwise, copy ID is set to 1.
Other scripts are provided to make embedding and detection easier. These
scripts contain corresponding GStreamer pipelines. The usage is described in
Appendix B.
In the test result tables (see below), the results belonging to one method are
grouped into one column set headed by the method name where one column
contains results of the test using the weight factor given in the column header.
Row sets represent results for single testing video sequences – ED, FB, KH,
PW, R, SM and W. Rows of the sets vary depending on eventual additional test
parameter.
5.1 Perceptibility
Perceptibility expresses amount of distortion caused by watermark
embedding. In other words, it indicates how visible the watermark is. It is
measured by peak signal-to-noise ratio (PSNR) which is mentioned in Section
4.2.2. The less the value of PSNR is the more perceptible the watermark is. We
can see in the first row set of Table 2 that the perceptibility grows up with
increasing weight factor. It is obvious that block method is the most perceptible
method because of the way of embedding.
The second row set of the table contains probabilities of watermark
detection success in non-attacked sequences as given by the detector. Note lower
probabilities when using noise method with low weight factors caused by the
interference from the video sequences and quantization.
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