Low Level Interface

The low level interface of MPIFiles.jl consists of a collection of methods that need to be implemented for each file format. It consists of the following methods

# general
version, uuid

# study parameters
studyName, studyNumber, studyUuid, studyDescription

# experiment parameters
experimentName, experimentNumber, experimentUuid, experimentDescription,
experimentSubject, experimentIsSimulation, experimentIsCalibration,
experimentHasMeasurement, experimentHasReconstruction

# tracer parameters
tracerName, tracerBatch, tracerVolume, tracerConcentration, tracerSolute,
tracerInjectionTime, tracerVendor

# scanner parameters
scannerFacility, scannerOperator, scannerManufacturer, scannerName, scannerTopology

# acquisition parameters
acqStartTime, acqNumFrames, acqNumAverages, acqGradient, acqOffsetField,
acqNumPeriodsPerFrame

# drive-field parameters
dfNumChannels, dfStrength, dfPhase, dfBaseFrequency, dfCustomWaveform, dfDivider,
dfWaveform, dfCycle

# receiver parameters
rxNumChannels, rxBandwidth, rxNumSamplingPoints, rxTransferFunction, rxUnit,
rxDataConversionFactor, rxInductionFactor

# measurements
measData, measDataTDPeriods, measIsFourierTransformed, measIsTFCorrected,
measIsBGCorrected, measIsFastFrameAxis, measIsFramePermutation, measIsFrequencySelection,
measIsBGFrame, measIsSpectralLeakageCorrected, measFramePermutation

# calibrations
calibSNR, calibFov, calibFovCenter, calibSize, calibOrder, calibPositions,
calibOffsetFields, calibDeltaSampleSize, calibMethod, calibIsMeanderingGrid

# reconstruction results
recoData, recoFov, recoFovCenter, recoSize, recoOrder, recoPositions

# additional functions that should be implemented by an MPIFile
filepath, systemMatrixWithBG, systemMatrix, selectedChannels

The interface is structured in a similar way as the parameters within the MDF. Basically, there is a direct mapping between the MDF parameters and the MPIFiles interface. For instance the parameter acqNumAvarages maps to the MDF parameter /acquisition/numAverages. Also the dimensionality of the parameters described in the MDF is preserved. Thus, the MDF specification can be used as a documentation of the low level interface of MPIFiles.

In-memory MDF

Since during data acquisition it is not advisable to write the data directly to an MDF file, there is also an in-memory representation. It can be created either empty by mdf = MDFv2InMemory() or with default values set by mdf = defaultMDFv2InMemory(). The same interface as described above applies to the in-memory version. When writing it to disk using saveasMDF("your/file/path/file.mdf", mdf) it is checked for consistency. If this check should fail with an error, use saveasMDF("your/file/path/file.mdf", mdf, failOnInconsistent=true). The default is to not fail in order to not lose measurement data in case of an error.