Thaichote (THEOS)

Key file name (use to open data set)	*.dim
Supported file extension(s)	.dim, .tif, .jpg

Sensor	Panchromatic and multispectral
Platform	Thaichote (formerly THEOS)
Data distributor	Geo-Informatics and Space Technology Development Agency (GISTDA), also known as the Thai Ministry of Science and Technology's Space Agency
Sections	Data product name and description Distribution disk files Returned data Returned metadata References

Name	Description	Version
Level 1A	Radiometric correction	First version
Level 2A	Radiometric and geometric correction with UTM projection	First version
Ortho Image	Geometric correction with digital elevation model (DEM)	First version
Pan Sharpened Image	Pansharpened image	First version

Note: Only Level 2A data has been tested.

File Name	File Type	Required	Contents
Image File: IMAGERY.TIF	GeoTIFF	Yes	Image data
Metadada File: METADATA.DIM	DIMAP	Yes	Metadata
PREVIEW.JPG	JPEG	No	Preview image
DIMAP product data sheet	PDF	No	Product annotation

Important notes to the user:

The GDB support of Thaichote data products is read-only.
Note: Thaichote was formerly named THEOS.
Thaichote data sets can be distributed on CD or DVD. GDB uses the above file names to identify the data product type. Therefore, to preserve compatibility with GDB, the file names must not be altered when the data is copied to another location from the CD or DVD.
To load the data set, select the metadata (DIMAP) file.

Data Product	Data Returned	Details
Thaichote image data	Four raster channels	Each raster channel has at least 6000 pixels and 6000 lines. The rasters are spatially coincident and the ground sample distance of the image data is 15 meters. The channels contain images for green, blue, near-infrared, and red wavelength bands. Image area at nadir is 90 km x 84 km, and data volume per band is approximately 36 megabytes.
Thaichote image data	One raster channel	Each raster channel has at least 12000 pixels and 12000 lines. The ground sample distance of the image data is 2 meters. Image area at nadir is 22 km x 24 km and data volume approximagely 144 megabytes.
Ephemeris data	One binary segment	The GDB returns ephemeris data as an orbit segment. This segment includes information about the satellite position, satellite altitude, IFOV, projection, sensor, orbit, and so on.
General information and metadata	Text segment	The main DIMAP file stores generic information about the product. This information can be imported as a text segment.

Name	Description	Values
MD_ColumnCount	Number of pixels per line	Integer
MD_RowCount	Number of lines per image	Integer
MD_NumberOfBands	Number of bands per data set	Integer
MD_PlatformName	Satellite platform name	THEOS
MD_SensorType	Sensor type	SENSE or DEM
MD_SensorModelName	Sensor model name	PAN or MS
MD_AlongTrack_Angle	Along track angle	Float
MD_AcrossTrack_Angle	Across track angle	Float
MD_SatelliteAltitude	Satellite altitude	Float
MD_Incidence_Angle	Incidence angle	Float
MD_SolarAzimuth	Solar azimuth	Float
MD_SolarElevationAngle	Solar elevation angle	Float
MD_SourceID	Source ID	String
MD_Acquisition_Date	Acquisition date	String
MD_Acquisition_Time	Acquisition time	String
MD_ProductType	Product type	THEOS1 SCENE
MD_FormatName	Format name	DIMAP
MD_SpatialResolutionX	Spatial resolution x	Float
MD_SpatialResolutionY	Spatial resolution y	Float
MD_SatPositions	Satellite positions	Array of float data with the following format: Time;x;y;z;x1;y1;z1 x, y, z are location x1,y1,z1 are velocity
MD_SatAttitudes	Satellite attitudes	Array of float data with the following format: Time;q0;q1;q2;q3

For more information, refer to the Thaichote product user guide by the Thai Ministry of Science and Technology's Space Agency.