TSDF metadata fields

TSDF metadata is represented as a dictionary (or a JSON object). In this section, we will list the fields within the TSDF format, as described in the format specification. In addition to the mandatory fields, any custom fields and structures can be added.

TSDF v0.1 mandatory fields

Field	Type	Description
study_id	str	Unique identifier for the particular study.
device_id	str	Specifies the device used for data collection.
subject_id	str	Unique identifier for the subject or participant in the study.
source_file_name	str	Name of the original source file containing the data.
endianness	str	Byte order for numerical values in binary data ("big" or "little").
metadata_version	str	Version information for the metadata.
start_iso8601	str	ISO 8601 time stamp for the start of the recording, with ms precision.
end_iso8601	str	Same as start_iso8601, but for the end of the recording.
file_name	str	The name of the file in consideration, e.g., "eeee.bin".
channels	str[]	Labels for each data channel (e.g.: [time] for time data or [X, Y, Z] for 3D accelerometry).
time_encode	str	Encoding type for time, e.g., "difference".
units	str[]	Units for each channel in the data, e.g., "ms" for milliseconds.
data_type	str	Number format of the measured data (e.g.: float).
bits	int	Bit-length of the number format (e.g., 32-bit).
rows	int	Number of rows in the data matrix.

Legacy fields

The following table lists the legacy fields from the time when the format was called TSDB, along with their updated counterparts:

Legacy field	Updated field	Updated data type
project_id	study_id	-
quantities	channels	str[]
units	units	str[]
datatype	data_type	-
start_datetime_iso8601	start_iso8601	-
end_datetime_iso8601	end_iso8601	-

Note

As presented in the table above, the quantities and units fields are required to be arrays within the TSDF standard.