Proposal 0.4

Only changes compared to the last version are listed here!!!

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Fix mandatory metadata

The metadata mandatory in all SOFA conventions have not been fixed yet. We propose to have the following metadata mandatory in all SOFA conventions:

Name	Default	Read-Only	Dimensions	Comment
GLOBAL_Conventions	SOFA	r
GLOBAL_Version	*	r		Insert the actual SOFA version here
GLOBAL_SOFAConventions	SimpleFreeFieldHRIR
GLOBAL_SOFAConventionsVersion	*			Insert the actual SOFA convention version here
GLOBAL_APIName	*			Insert the API Name here
GLOBAL_APIVersion	*			Insert the API Version here
GLOBAL_AuthorContact
GLOBAL_License	No license provided, ask the author for permission
GLOBAL_Organization
GLOBAL_RoomType	free field
GLOBAL_DataType	FIR
GLOBAL_History
GLOBAL_Source				The method of production of the original data. If it was model-generated, source should name the model and its version, as specifically as could be useful. If it is observational, source should characterize it.
GLOBAL_Title				A succinct description of what is in the dataset
GLOBAL_References				Published or web-based references that describe the data or methods used to produce it
GLOBAL_Comment
GLOBAL_DatabaseTimeCreated	*			will be updated when saving and not existing or empty
GLOBAL_DatabaseTimeModified	*			will be updated each time when saving
I	1	r	I
I_LongName	singleton dimension	r
R	2		R
R_LongName	number of receivers	r
E	1		E
E_LongName	number of emitters	r
N	-		N
N_LongName	index
N_Units	sampling period
M	-		M
M_LongName	number of measurements	r
C	3	r	C
C_LongName	coordinate triplet	r
ListenerPosition	[1 0 0]		IC, MC
ListenerPosition_Type	cartesian
ListenerPosition_Units	meter
ReceiverPosition	[0 -0.09 0; 0 0.09 0]		rCI, rCM
ReceiverPosition_Type	cartesian
ReceiverPosition_Units	meter
SourcePosition	[0 0 0]		IC, MC
SourcePosition_Type	cartesian
SourcePosition_Units	meter
EmitterPosition	[0 0 0]		eCI, eCM
EmitterPosition_Type	cartesian
EmitterPosition_Units	meter
Data.IR	[1 1]		mRn	Only mandatory when DataType is FIR
Data.SamplingRate	48000		I	Only mandatory when DataType is FIR
Data.SamplingRate_Units	hertz			Only mandatory when DataType is FIR

Note: we consider the Data as mandatory, thus, if DataType is default (=FIR) then Data.FIR, Data.SamplingRate, and Data.SamplingRate_Units must be provided. Otherwise, the correct Data-fields must be provided.

Legend:

• Name: the name of the metadata
  • An underscore (_): the metadata is an attribute
    • GLOBAL_: the metadata is a global attribute
    • X_Y: the metadata is an attribute Y of the variable X
  • No underscore: the metadata is a variable
  • Data.X: the metadata is structured within the data
• Default: default value for the metadata
  • An asterisk (*): special handling required, mentioned in the column Comment
• Flags:
  • r: read-only, must be the default value and must not be changed
• Dimensions: dimensions of the metadata (see SOFA specifications for more explanations)
  • lower case: the variable size in that dimension determines the dimension size in the file
  • upper case: variable must be of that dimension (or one of these dimensions)

Fix versioning of SOFA and conventions

Three version types:

• Version: defines the version of the general SOFA specs
• ConventionsVersion: defines the version of the particular SOFA conventions. Could be merged with Version, but then, when we change something a Conventions, each time the version for the general SOFA specs would need to be increased. Not clear how to proceed. Maybe the AES standardization process will clarify. Until then: no merging, to be on the safe side.
• APIVersion: clearly separated from the rest.