ERMapper Format

The ERMapper map format is implemented by Dinamica EGO as follows:

Maps are represented using two different files:

The header file uses the extension “.ers” and stores the map meta data.

The data file does not use an extension and stores the cells from all map layers interlaced by lines. Compression is never used.

Due to format limitations, maps whose cells are represented using 1 bit per cell are written using 8 bits per cell, unsigned.

Blanks in layer names are automatically replaced by “_” (underscore) when reading maps.

It is not possible to read or write maps bigger than 4 Gigabytes (4294967296 bytes) even on Dinamica EGO 64.

Header Format

The ERMapper header written by Dinamica EGO always have the format below:

DatasetHeader Begin
Version = "6.0"
LastUpdated = %Date%
DataSetType = ERStorage
DataType = Raster
ByteOrder = %ByteOrder%
CoordinateSpace Begin
Datum = "%Datum%"
Projection = "%Projection%"
CoordinateType = %CoordinateType%
Rotation = 0:0:0.0
CoordinateSpace End
RasterInfo Begin
CellType = %CellType%
NullCellValue = %Null%
CellInfo Begin
Xdimension = %CellWidth%
Ydimension = %CellHeight%
CellInfo End
NrOfLines = %Lines%
NrOfCellsPerLine = %Columns%
RegistrationCoord Begin
Eastings = %RegistrationCoordinateX%
Northings = %RegistrationCoordinateY%
RegistrationCoord End
RegistrationCellX = %RegistrationCellX%
RegistrationCellY = %RegistrationCellY%
NrOfBands = %Layers%
BandId Begin
Value = "%LayerName1%"
BandId End
...
BandId Begin
Value = "%LayerNameN%"
BandId End
RegionInfo Begin
Type = Class
RegionName = "%ClassName1%"
RBGcolour Begin
Red = %Red1%
Green = %Green1%
Blue = %Blue1%
RBGcolour End
ClassNumber = %Class1%
RegionInfo End
...
RegionInfo Begin
Type = Class
RegionName = "%ClassNameN%"
RBGcolour Begin
Red = %RedN%
Green = %GreenN%
Blue = %BlueN%
RBGcolour End
ClassNumber = %ClassN%
RegionInfo End
RasterInfo End
DatasetHeader End

The text delimited by “%” is replace by the corresponding value in the map instance.