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

Data product name and description
Distribution disk files
Returned data
Returned metadata

Data product name and description

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.

Distribution disk files

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:

  1. The GDB support of Thaichote data products is read-only.
    Note: Thaichote was formerly named THEOS.
  2. 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.
  3. To load the data set, select the metadata (DIMAP) file.

Returned data

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.

Returned metadata

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:
x, y, z are location
x1,y1,z1 are velocity

MD_SatAttitudes Satellite attitudes

Array of float data with the following format:


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

© PCI Geomatics Enterprises, Inc.®, 2023. All rights reserved.