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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.