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CerebusOSS / CereLink

Blackrock Microsystems Cerebus Link for Neural Signal Processing
BSD 2-Clause "Simplified" License
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Continuous analog data are different if extracted using c++ code or openNSx.m in Matlab #75

Open FlavioRaschella opened 7 years ago

FlavioRaschella commented 7 years ago

Hi,

I managed to extract real-time analog input data on my c++ code on Visual Studio. I use an existing recording played back on NPlayServer. What I did is to get the analog input samples and copy them into a .txt file, in an iterative process. When I plot them, they look similar to the signal displayed on Central, using the NPlayServer.

Instead, when I extract the data directly from the recording file using openNSx.m in Matlab, the data look different (Figures 1 and 2 ). Most of the time the data saturates. It almost seems that the c++ dataset is the filtered version of the matlab dataset.

noisedata Figure 1: noisy dataset (blue: extracted using matlab; red; extracted using c++ code)

recdata Figure 2: muscle contraction dataset (blue: extracted using matlab; red; extracted using c++ code)

Let me know if you may have ideas of why it happens.

Thanks in advance, Flavio

dashesy commented 7 years ago

It looks like data corruption when read by openNSX, I do not think it is related to filters

FlavioRaschella commented 7 years ago

Does it mean that the problem is related to openNSX?

Flavio

On 01 Aug 2017, at 20:16, Ehsan Azar notifications@github.com wrote:

It looks like data corruption when read by openNSX, I do not think it is related to filters

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/dashesy/CereLink/issues/75#issuecomment-319453064, or mute the thread https://github.com/notifications/unsubscribe-auth/AZuhEo6dTEC3Z-7HlBx2YXsyyUZ6qTTXks5sT2uFgaJpZM4NDEWg.

dashesy commented 7 years ago

Also you can capture the raw, that will not be filtered for certain and you can then compare.