问题
I am trying to make an ECG viewer reading DICOM files.
I get all data (like Channel Definition Seqeunce), also got the waveform samples to each channel. My problem is that there is a Tag (Channel Sensitivity), and I can't figure out it's meaning.
What purpose does it have?
回答1:
After you have the raw value for a sample you have to apply some transformations defined by several tags.
Channel Sensitivity is a mandatory field when samples represent defined units and it must be used in conjunction with Channel Sensitivity Correction Factor, Channel Baseline and Channel Sensitivity Units. It represents numeric value of unit quantity of sample.
What does it means? Suppose you did read the sample, you added the bias of Channel Baseline and applied the correction factor of Channel Sensitivity Correction Factor.
Now that value matches Channel Sensitivity with the unit of Channel Sensitivity Units. For example suppose you acquired a constant 5 mV signal, you may set Sensitivity to 5 mV, write to disk the value 1 for each sample and use a Channel Sensitivity Correction Factor of 5. After decoding you'll have back 5 mV. You do not need to consider this (but you have to consider its unit) if you'll display the signal with the same sensitivity.
For your reference: http://dicomlookup.com/html/03_03PU.html#LinkTarget_229394
来源：https://stackoverflow.com/questions/12855400/rchannel-sensitivity-in-dicom-waveforms