Post Processing
Post processing allows a user to take B-Scan data and "Scan" it as if it were data coming from an A/D board. Post processing is generally used in offline installs of ODIS.
Activating Post Processing
In order to activate post-processing, it is necessary to install ODIS as a "Post Processing". A Post-Processing Token File is also required.
Post Processing Mode
Once the tag is set, restart ODIS. You should see an "ALPostProcessing" channel on the digital oscilloscope.
The Post-processing oscilloscope has a simple set of Board Settings controls: a "WF" and "Page" input, and a simple slider bar. These can be used to navigate through the B-Scan data. Press the Controls toolbar button at the upper left of the Digital Oscilloscope to display the controls tab, then click on the Board Controls tab.
Attaching B-Scan data for Post-Processing
To attach B-scan data, load a collection with saved B-Scans. When you page to the image containing the B-Scan data, a button with a "Link" icon will appear in the upper right of the image.
Note: it is also possible to simply drag the image icon or the B-Scan image to the scope: this will attach any B-Scan data present.
Once the user clicks on the link icon, the data will be "attached" to the post processing scope. The user can close the original image at this time if desired, although the scan collection must remain in memory.
Once linked, the post-processor will display the data in a continuous loop. The current B-Scan page and the index of the waveform being displayed on that page are shown in the Board Settings tab.
If a user wants to look at a particular waveform , un-check the "loop" box and either drag the scroll bar to the desired location, or enter the positions manually in the WF and Page inputs. This can be especially useful for comparing results on the scope with results in the post processed data.
Note: make sure to turn Loop back on before scanning.
Once the data is connected, the user can add any gates (including B-scans) that he wishes to the data.
Post-Process Scanning
Scanning with the Post-Processor is exactly like any other scanning mode, with the exception that the user cannot establish scan dimensions. In order to tell the user to use Post-Processing, two settings must be applied:
- Set the scan for Unidirectional scanning
- The "Post-Process" button must be checked.
For Basic users, these checkboxes are located on the Scan Settings tab of the Setup dialog. For Advanced users, the Unidirectional checkbox is located on the Linear tab of the scan Manager, and the Post Process checkbox is located on the Options tab.
Note: Advanced users must use the Linear scan tab in order to do post-processing collection.
The user can now begin scanning using the "Start Scan" button. The scan will proceed just like any other scan.
Once the scan is complete, it can be saved and reloaded like any other collection.
Current Post-Processing Limitations
- Only one channel of data may be post-processed at a time.
- Can only perform Linear scans on B-Scan data
- Cannot change the image dimensions: any scans will have the same dimensions as the original collection.
- Pausing will restart the scan from the beginning