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.