Chapter 4. Open a Signal

After starting RASCHlab, an empty workspace is shown. In this workspace the signal and other information about the signal will be shown. Now the first step will be to open a signal. To do this, select the menu entry 'File/Open...' or press the open button on the toolbar (an opening folder; the first button from left). This will open the signal selection dialog box. Figure 4-1 shows the screen shot with the dialog box. The signal selection dialog box is similar to the file browser in Windows, on the left side you can select the folder. On the right side, the signals in the selected folder will be shown. (Only the signals which are supported by libRASCH are shown.)

Now select the folder 'LIBRASCH_ROOT/examples/database' on Linux systems and 'LIBRASCH_INSTALL_ROOT\examples\database' on Windows systems on the left side[1]. After selecting the folder, the available signals will be shown. Please select the signal named '100s'. This is a short ECG (one minute) from the PhysioNet database. To open the signal, you can double click on the signal-name or select the signal by clicking once on the signal-name and then click on the OK button. Then the signal will be shown in the signal window. Figure 4-2 shows RASCHlab with the signal window showing the ECG. The signal window is a libRASCH view-plugin.

In the signal window, all channels of a measurement are shown. When the measurement contains more than one type of signal (e.g. ECG and arterial blood pressure) then each type of signal will be shown in their own signal window (for an example see Figure 6-1). To do this, libRASCH has to "detect" which signals are stored in a measurement. In general purpose file formats (e.g. file formats used by ADC systems), libRASCH tries to estimate the signal-type by the channel name. In file formats which have a fixed channel/signal-type relation, the signal type is set by the plugin supporting the file format.