biomedical toolkit ECG feature extractor

[T2dei]

Hello!

I am using the Biomedical toolkit with labVIEW 2014. I want to generalize the given example "ECG Feature Extractor.vi" to be eligible to extract any ECG signal's features. Can someone help me understand the meaning of the blocks in a red circle number 1 of the attached picture? How did he decide on these values. 

Also, on what basis did he choose the frequency and ripple spectrums in the red circle number 2 of the attached picture.

Thanks.

[ShamWOW!!]

Hello!

Do you mind letting me know where you found this VI? Was it already in LabVIEW, or did you find it in a community example?

[T2dei]

Its in the examples of the toolkit. You will find it If you select find examples and searched under biomedical

[ShamWOW!!]

From that VI, the blocks in circle 1 are the QRS detector parameters that change specifically on the signal type (Normal, Hyperkalemia, and Tachycardia). You can find the information on all of the inputs of any subVI by opening context help (ctrl+H), hovering over the subVI, and then selecting detailed help once the context help updates to the subVI. From that screen, the subVI’s purpose is explained and the inputs and outputs are documented as well.

I cannot say as to where the creator got those values in circle 1 and 2, other than it might have been found to be recommended somewhere at some point in time. However, if you try it out and find that it isn’t creating the waveform or data that you want, feel free to change it as every person is different. The constants in circle 2 are going to change which data gets filtered out as well as the ripple specs. The data from an ECG might be different from person to person, so changing the constants really isn’t out of the question.

[T2dei]

Thank you. That was really helpful.
One last question about circle 1. My App is the reverse of this example. I want to add different ECG signals and based on the features extracted the program detects the type of the signal.
Should I fix circle 1 to the normal type or what do you suggest me?

[ShamWOW!! · Accepted solution]

It sounds like it should be your call. I would definitely test it out the VI and see if it creates results that are intended. If not, then change the values to whatever you like. From what the constants look like, locking the parameters in to the default case will probably create the more general case signal.

By looking at the detailed help for the ‘ECG Feature Extractor (Waveform All Features).vi’ that the constants that are in, circle one constants aren’t even necessary inputs as without them, the subVI uses those ‘normal’ values as defaults. If you completely get rid of circle 1, then it essentially ‘locks’ it in to those constants because those value are the default values.

All in all, just test it out and see if it gives you the results you are looking for. Constants are easy to modify quickly. The detailed help for every subVI you use should give enough information about the inputs to modify in an educated manner. You could even change the constants to controls to make it easier to change on the fly.

[mohamedtanveej17]

hi 

I'm using LabVIEW 2015 with the biomedical toolkit and try to work on qrs detection on ecg signals.

The issue is LabVIEW shows a warning when I worked  in feature extractor main vi .It shows that modules and drivers where missing . i have attached a screenshot of it here

[Dafrizzy]

Hi Mohamed,

The biomedical toolkit requires the Advanced Signal Processing Toolkit to be installed on your machine. You should be able to use this toolkit if you have an academic site license for LabVIEW or if you have the LabVIEW Full Development System installed. You can download the Advanced Signal Processing Toolkit from the page linked below:

Evaluate Image and Advanced Signal Processing Algorithms with NI LabVIEW

If you are still having issues getting the Biomedical toolkit VIs to run, I would recommend starting a new forum post so it can gain more visibility since this post already has a solution.