How can I find QRS complex duration of ECG signals?

I need to find QRS complex duration of ECG signals.From the definition,it includes Q,R and S points.I am attaching an image,to give a picture of what exactly I want. I have done some processing on the ECG signal.I need to find the QRS complex interval for the given ECG signal.Can somebody can suggest some kind of general purpose logic which can be used for finding the QRS interval.I know that for finding accurate intervals,the intermediate signal values apart from Q,S,R,T,U,P needs to be along the isoelectric reference.I would really appreciate some suggestions for flattening the other values.

[Edward Chavez]

Hi, I'm also looking for it, it's possible to calculate it? with just one column as well as your file ecg_RAW.xls, please i only need qrs and t interval, my email- [e-mail]

[Sebinraj S]

can you please send me the code.