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which is why today there are few experts in the interpretation of acoustic signals in the human
heart [6].
2 Methodology
2.1 Design Process
PCGs
and other biomedical signals are often graphical representation of the underlying signal. Files consist
of a header containing non-signal information (such as specific data related to patient), and a series of
numbers relating to the patient's biomedical signal. The crucial task for the development of the project was
to develop the file-reading and generating protocol. This included interpretation of the header, the capture
of basic patient information, and the transformation of a set of numbers to and from a graphic format. This
involved the development of various mathematical algorithms to process the numbers in the file, resizing
and resampling the data to fit the sizes handled by C#, as well as adjusting the size and layout of the output
graphs to the size of a computer screen.
We proceeded to sort algorithms, develop a well-structured class, define its attributes and methods,
determine the scope of the methods, determining levels of protection for each method (such as
redundancy), and so on. From this classification work came the Biosignal class with its specific attributes and
processing methods.
Finally, we entered the test phase, in which PCGs from previously digitized files were used to test
deployment, data recording, on-screen manipulation such as zoom, and comparison of multiple
simultaneous signals.
2.2 System Description
The user interaction was intended to be intuitive, offering user-friendly documents that contain the set of
values that form the biomedical signal. This can be repeated if required the observation of several signals
simultaneously. A user can set background colors and line grid for better readability under a wider range of
conditions. Graph visualization tools allowed operations to be performed on one graph or synchronized
across multiple. A user can also capture notes related to each observed signal to keep track of the analysis
[7].
Achieving this required design and programming that resulted in a set of properties that defined and
delineated the characteristics of the display of a signal. The main properties used were: file, width, height,
pos (position), hfactor (horizontal factor), vfactor (vertical factor), backColor (background), lineColor, rColor,
rWidth and lineWidth. These properties belong to the class Biosignal and are available for use in the
methods that were set as goals.
To perform the functions of stretching, zooming, scrolling and marking of the graphs, functions were
programmed including application of geometry and manipulation of massive numerical quantities, which
reside in the code for the “Click” event of several buttons and are then applied on Display graphs using the
methods Display(), Refresh(), Reset(), Hide(), Close(), Play() and Showmark().
The general form of system operation can be described in summary as follows: A system
where the numerical data reside in a structure of powerful features (List <>) and has the rich
algorithmic functions that are activated with the Click event. These features result in new values
for the properties that define the display. Then run the methods needed to re-deploy the modified
charts on the screen.