Processing First Difference (delta coding) ECG signal after Huffman decoding

I have been trying to decode a file from a GE Marquette MAC5500 series ECG cart, so far I have extracted the median and lead rhythm data and run it through a Huffman decoder. The resultant data is First Difference encoded and after lots of C# coding I've not got to the right results. Part of the waveform is coded using one Huffman table and the QRS section uses another. The part outside of the QRS waveform looks ok to me and I do have a known working waveform to compare it to. However the QRS section is wrong and looks to wide (too many samples). Does anyone have any experience with First or Second Difference coding and / or ECG data from a GE Marquette cart??

[René]

Hi Dan,

Did you ever solve this problem?

Best,

René

[Ryan Hoffman]

Hi Dan, René,

Checking back to ask - were either of you able to make any progress with this problem? What Huffman tables were you using to decode the waveforms?

Thanks,

-- Ryan