VisAD Binary File Format

Objects

OBJ_COORDSYS

A VisAD coordinate system object. For version 1, these are all serialized.

Bytes	Type	Description
1	OBJ_COORDSYS	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
1	FLD_COORDSYS_SERIAL	Serialized CoordinateSystem marker
len	serialized object	A serialized CoordinateSystem object
1	FLD_END	End-of-object marker

OBJ_DATA

A VisAD Data object.

Bytes	Type	Description
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	byte	Data object byte value
?	--	Remainder of Data object
1	FLD_END	End-of-object marker

See the DATA section below for the formats of the various standard Data objects.

OBJ_DATA_SERIAL

A non-standard Data object, written as a serialized Java object.

Bytes	Type	Description
1	OBJ_DATA_SERIAL	Start-of-object marker
4	int	Serialized object length
len	serialized object	A serialized Data object
1	FLD_END	End-of-object marker

OBJ_ERROR

A VisAD error estimate.

Bytes	Type	Description
1	OBJ_ERROR	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
8	double	Error value
8	double	Mean
8	long	Number of values
1	FLD_INDEX_UNIT	If CoordinateSystem has a Unit
4	Unit index
1	FLD_END	End-of-object marker

OBJ_MATH

A VisAD MathType.

Bytes	Type	Description
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
1	byte	MathType byte value
?	--	Remainder of MathType object
1	FLD_END	End-of-object marker

See the MATH section below for the formats of the various standard MathTypes

OBJ_MATH_SERIAL

A non-standard MathType, written as a serialized Java object.

Bytes	Type	Description
1	OBJ_MATH_SERIAL	Start-of-object marker
4	int	Serialized object length
len	serialized object	A serialized MathType object
1	FLD_END	End-of-object marker

OBJ_UNIT

A VisAD unit specification.

Bytes	Type	Description
1	OBJ_UNIT	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
4	int	Identifier string length
len	string	Identifier string
4	int	Description string length
len	string	Description string
1	FLD_END	End-of-object marker

MathTypes

MATH_FUNCTION

Bytes	Type	Description
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object (should always be 14)
4	int	Index number
1	MATH_FUNCTION	FunctionType marker
4	int	Function domain MathType index
4	int	Function range MathType index
1	FLD_END	End-of-object marker

MATH_QUANTITY

Bytes	Type	Description	Comment
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
1	MATH_QUANTITY	Quantity MathType marker
4	int	Name string length
len	string	Name string
4	int	Unit specification string length
len	string	Unit specification string
1	FLD_SET_FOLLOWS_TYPE	The Set associated with this object follows immediately after this object's FLD_END byte	Only specified if there is a Set associated with this MathType
1	FLD_END	End-of-object marker

MATH_REAL_TUPLE

Bytes	Type	Description	Comment
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
1	MATH_REAL_TUPLE	RealTupleType marker
4	int	Number of MathType tuples	The tuple dimension is followed by the appropriate number of ints to hold the list of MathType indices
4	int	First tuple member index
...
4	int	Last tuple member index
1	FLD_INDEX_COORDSYS	Marker for MathType CoordinateSystem index.	Only specified if there is a CoordinateSystem associated with this MathType
4	int	CoordinateSystem index
1	FLD_SET_FOLLOWS_TYPE	The Set associated with this object follows immediately after this object's FLD_END byte	Only specified if there is a Set associated with this MathType
1	FLD_END	End-of-object marker

MATH_REAL

Bytes	Type	Description	Comment
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
1	MATH_REAL	RealType marker
4	int	Attribute mask
4	int	Name string length
len	string	Name string
1	FLD_INDEX_UNIT	Marker for MathType Unit index	Only specified if there is a Unit associated with this MathType
4	int	Unit index
1	FLD_SET_FOLLOWS_TYPE	The Set associated with this object follows immediately after this object's FLD_END byte	Only specified if there is a Set associated with this MathType
1	FLD_END	End-of-object marker

MATH_SET

Bytes	Type	Description
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object (should always be 10)
4	int	Index number
1	MATH_SET	SetType marker
4	int	Domain MathType index
1	FLD_END	End-of-object marker

MATH_TEXT

Bytes	Type	Description
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
1	MATH_TEXT	TextType marker
len	string	Name string
1	FLD_END	End-of-object marker

MATH_TUPLE

Bytes	Type	Description
1	OBJ_MATH	Start-of-object marker
4	int	Number of bytes before end of object
4	int	Index number
1	MATH_TUPLE	TupleType marker
4	int	First tuple member index
...
4	int	Last tuple member index
1	FLD_END	End-of-object marker

Data Types

Note that for all Data types which contain one or more embedded data objects, the OBJ_DATA marker may be preceeded by any number of OBJ_COORDSYS, OBJ_ERROR, OBJ_MATH, OBJ_MATH_SERIAL or OBJ_UNIT objects.

Also, any field marked as containing an OBJ_DATA object may instead contain an OBJ_DATA_SERIAL object.

DATA_DOUBLE_SET

Coming soon.

DATA_FIELD

Bytes	Type	Description	Comment
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	DATA_FIELD	FieldImpl/FileField marker
4	int	FunctionType index
1	FLD_SET	Marker for default Set object.	Only specified if there is a default Set.
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Set object byte value
?	--	Remainder of Set object
1	FLD_DATA_SAMPLES	Marker for list of Data fields.	Only specified if there are Data fields.
4	int	Number of Data fields
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	First field Data object byte value
?	--	Remainder of first field Data object
...
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Last field Data object byte value
?	--	Remainder of last field Data object
1	FLD_END	End-of-object marker

DATA_FLAT_FIELD

Bytes	Type	Description	Comment
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	DATA_FLAT_FIELD	FlatField/FileFlatField marker
4	int	FunctionType index
1	FLD_SET	Marker for domain Set object.	Only specified if there is a domain Set.
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Set object byte value
?	--	Remainder of Set object
1	FLD_DATA_SAMPLES	Marker for list of Data fields.	Only specified if there are Data fields.
4	int	Number of Data fields
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	First field Data object byte value
?	--	Remainder of first field Data object
...
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Last field Data object byte value
?	--	Remainder of last field Data object
1	FLD_INDEX_COORDSYS	Marker for FlatField CoordinateSystem index.	Only specified if there is a CoordinateSystem associated with this FlatField
4	int	CoordinateSystem index
1	FLD_RANGE_COORDSYS	Marker for list of range CoordinateSystems	Only specified if there is are CoordinateSystems associated with this FlatField's range.
4	int	List length
4	int	First CoordinateSystem index
...
4	int	Last CoordinateSystem index
1	FLD_SET_LIST	Marker for list of range default Sets.	Only specified if there are default Sets for this FlatField's range.
4	int	Number of range Sets.
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	First Set object byte value
?	--	Remainder of first Set object
...
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Last Set object byte value
?	--	Remainder of last Set object
1	FLD_INDEX_UNITS	Marker for list of range Units	Only specified if there is are Units associated with this FlatField's range.
4	int	List length
4	int	First Unit index
...
4	int	Last Unit index
1	FLD_END	End-of-object marker

DATA_FLOAT_SET

Coming soon.

DATA_GRIDDED_1D_DOUBLE_SET,
DATA_GRIDDED_2D_DOUBLE_SET,
and DATA_GRIDDED_3D_DOUBLE_SET

Coming soon.

DATA_GRIDDED_SET,
DATA_GRIDDED_1D_SET,
DATA_GRIDDED_2D_SET,
and DATA_GRIDDED_3D_SET

Coming soon.

DATA_INTEGER_1D_SET,
DATA_INTEGER_2D_SET,
DATA_INTEGER_3D_SET,
and DATA_INTEGER_ND_SET

All four of these Data objects use the same format, differing only in the dimension of their FLD_LENGTHS or FLD_INTEGER_SETS list.

Bytes	Type	Description	Comment
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	byte	Set marker	One of DATA_INTEGER_1D_SET, DATA_INTEGER_2D_SET, DATA_INTEGER_3D_SET or DATA_INTEGER_ND_SET,
4	int	SetType index
1	FLD_LENGTHS	Marker for list of lengths		At most one of FLD_LENGTHS and FLD_INTEGER_SETS will be present
4	int	List length
4	int	First Set length
...
4	int	Last Set length
1	FLD_INTEGER_SETS	Marker for list of Integer1DSets.	It is not legal for FLD_INTEGER_1D_SET to contain this list.
4	int	Number of Integer1DSets
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	First Integer1DSet object byte value
?	--	Remainder of first Integer1DSet object
...
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Last Integer1DSet object byte value
?	--	Remainder of last Integer1DSet object
1	FLD_INDEX_COORDSYS	Marker for integer Set CoordinateSystem index.	Only specified if there is a CoordinateSystem associated with this integer Set
4	int	CoordinateSystem index
1	FLD_INDEX_UNITS	Marker for list of range Units	Only specified if there is are Units associated with this integer Set range.
4	int	List length
4	int	First Unit index
...
4	int	Last Unit index
1	FLD_INDEX_ERRORS	Marker for list of range Errors	Only specified if there is are Errors associated with this integer Set.
4	int	List length
4	int	First Error index
...
4	int	Last Error index
1	FLD_END	End-of-object marker

DATA_IRREGULAR_1D_SET,
DATA_IRREGULAR_2D_SET,
and DATA_IRREGULAR_3D_SET

Coming soon.

DATA_LINEAR_1D_SET,
DATA_LINEAR_2D_SET,
DATA_LINEAR_3D_SET,
DATA_LINEAR_ND_SET,
and DATA_LINEAR_LATLON_SET

All five of these Data objects use the same format, differing only in the dimension of their FLD_FIRSTS/FLD_LASTS/FLD_LENGTHS or FLD_LINEAR_SETS list.

Bytes	Type	Description	Comment
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	byte	Set marker	One of DATA_LINEAR_1D_SET, DATA_LINEAR_2D_SET, DATA_LINEAR_3D_SET or DATA_LINEAR_ND_SET,
4	int	SetType index
1	FLD_FIRSTS	Marker for list of lengths		At most one of FLD_FIRSTS/FLD_LASTS/FLD_LENGTHS and FLD_LINEAR_SETS will be present
4	int	List length
4	int	First initial Set value
...
4	int	Last initial Set value
1	FLD_LASTS	Marker for list of final Set values.
4	int	List length
4	int	First final Set value
...
4	int	Last final Set value
1	FLD_LENGTHS	Marker for list of lengths
4	int	List length
4	int	First Set length
...
4	int	Last Set length
1	FLD_LINEAR_SETS	Marker for list of Linear1DSets.	It is not legal for FLD_LINEAR_1D_SET to contain this list.
4	int	Number of Linear1DSets
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	First Linear1DSet object byte value
?	--	Remainder of first Linear1DSet object
...
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Last Linear1DSet object byte value
?	--	Remainder of last Linear1DSet object
1	FLD_INDEX_COORDSYS	Marker for integer Set CoordinateSystem index.	Only specified if there is a CoordinateSystem associated with this integer Set
4	int	CoordinateSystem index
1	FLD_INDEX_UNITS	Marker for list of range Units	Only specified if there is are Units associated with this integer Set range.
4	int	List length
4	int	First Unit index
...
4	int	Last Unit index
1	FLD_INDEX_ERRORS	Marker for list of range Errors	Only specified if there is are Errors associated with this integer Set.
4	int	List length
4	int	First Error index
...
4	int	Last Error index
1	FLD_END	End-of-object marker

DATA_LIST1D_SET

Coming soon.

DATA_PRODUCT_SET

Coming soon.

DATA_REAL

Bytes	Type	Description	Comment
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	DATA_REAL	Real marker
4	int	RealType index
8	double	Value
1	FLD_INDEX_UNIT	Marker for Real Unit index.	Only specified if there is a Unit associated with this Real
4	int	Unit index
1	FLD_INDEX_ERROR	Marker for Real ErrorEstimate index.	Only specified if there is an ErrorEstimate associated with this Real
4	int	ErrorEstimate index
1	FLD_END	End-of-object marker

DATA_REAL_TUPLE

Bytes	Type	Description	Comment
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	DATA_REAL_TUPLE	RealTuple marker
4	int	TupleType index
1	FLD_REAL_SAMPLES	Marker for list of Real tuples.	Only specified if there are non-trivial Real tuples	At most one of FLD_REAL_SAMPLES and FLD_TRIVIAL_SAMPLES will be present, and it's possible for neither to be present.
4	int	Number of Real tuples
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	First DATA_REAL marker
?	--	Remainder of first Real object
...
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Last DATA_REAL marker
?	--	Remainder of last Real object
1	FLD_TRIVIAL_SAMPLES	Marker for list of Real values.	Only specified if there are trivial Real tuples
4	int	Number of Real values.
8	double	First tuple value
...
8	double	Last tuple value
1	FLD_END	End-of-object marker

DATA_SINGLETON_SET

Coming soon.

DATA_TEXT

Bytes	Type	Description
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	DATA_TEXT	Text marker
4	int	TextType index
4	int	Text string length
len	string	Text string
1	FLD_END	End-of-object marker

DATA_TUPLE

Bytes	Type	Description	Comment
1	OBJ_DATA	Start-of-object marker
4	int	Number of bytes before end of object
1	DATA_TUPLE	Tuple marker
4	int	TupleType index
1	FLD_DATA_SAMPLES	Marker for list of Data tuples.	Only specified if there are Data tuples
4	int	Number of Data tuples
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	First tuple Data object byte value
?	--	Remainder of first tuple Data object
...
1	byte	OBJ_DATA
4	int	Number of bytes before end of object
1	byte	Last Tuple Data object byte value
?	--	Remainder of last Tuple Data object
1	FLD_END	End-of-object marker

DATA_UNION_SET

Coming soon.

Data Field Notes

FLD_SET_FOLLOWS_TYPE

Because some MathTypes contain a default Set with uses that MathType in the definition of its SetType, that Set cannot be encapsulated within the MathType's object. Instead, a FLD_SET_FOLLOWS_TYPE byte indicates that, immediately after the end of the MATH_* object's FLD_END marker, an OBJ_DATA object can be found which will be used to build this MathType's default Set object.