The output file from CDSPOTC is used as input to the programs SMODEL and SORTHO.
Progress of this program can be monitored. See MONITOR section.
See Also: SATORTHO, MLANDC, MSPOT, MSPOTC, MEOSAT, CDSPOT, CDLANDC, SMODEL, SORTHO, SDEM, SEPIPRO, SDEMCPY, SDEMMAN, SHL, FIMPORT
Name Prompt Count Type CDDIR CD Directory 1-64 Char FILE Database File Name 1-64 Char CDIC CD Input Channel list 1-16 Int TEX1 Database Descriptive Text 1 0-64 Char REPORT Report Mode: TERM/OFF/filename 1-64 Char The following parameters receive output: ORBIT Orbit Segment 1 Int
EASI>CDDIR="cddir"See example on how to enter the CDDIR for different operating systems.
EASI>FILE="filespec"
EASI>CDIC=i,j,...,pThere is 1 channel on a SPOT panchromatic CD, and there are 3 channels on a SPOT multispectral CD. SPOT panchromatic requires about 40 Mbytes of disk space, and SPOT multispectral requires about 10 Mbytes of disk space (30 Mbytes for all 3 channels). This amount of space must be available before CDSPOTC is run.
EASI>TEX1="string"Note: If TEX1 is defaulted, the following fields of the File Header in the output PCIDSK image database created will hold the following information:
FH5 receives the tape ID, satellite Sensor and satellite Track.
FH7.1 receives the acquisition Date and scene Centre (longitude,
latitude in decimal degrees.)
FH7.2 will be blanked for now.
EASI>REPORT="filename" EASI>REPORT= | defaults to terminal outputNote: The following names have special meaning:
EASI>REPORT="TERM" | generates reports on your terminal EASI>REPORT="DISK" | generates reports on file "IMPRPT.LST" EASI>REPORT="OFF" | switch off report generation
The file names on the CD should look like the following:
VDF_DAT.00n, VDF_SUP.00n, DAT_SUP.00n, LEA_0n.00n, DAT_01.00n, DAT_02.00n, DAT_03.00n where n is between 1 to 3.The Canadian LGSOWG CD makes available different levels of processing. This program only supports the level 1 CD. Level 1 is radiometrically corrected, with detector offsets applied. For different level CDs, the FIMPORT program can be used.
NOTE : This program only support CDs generated by CCRS. CDs generated by MDA-RICHMOND MERIDIAN format are not supported.
Level 1 CD has two different volumes: imagery and supplemental. The imagery logical volume contains the imagery data itself, and related image-synchronized information, plus ONLY that support data related to the scene. Ephemeris and attitude data are specifically excluded from this volume, as is station-specific information, such as annotation data. The supplemental logical volume contains station-related processing data, such as annotation, ephemeris and attitude data, and GCP and Payload Correction (PCD) information. The user should expect to find differences in the definition of this logical volume as supplied by different agencies. The supplemental volume is usually optional (user's choice) and may come before or after the imagery logical volume. For this program, it is recommended that the user supply the supplemental volume in order to improve the accuracy of the results. If the supplemental volume is not used, approximate values will be used in the program.
The CDSPOTC program will extract from the CD the geographic coordinates of the scene centre and the 4 corner points, and the corresponding pixel and line positions, if the values are available. The values are stored in the ORBIT segment. These points can be used as GCPs input to the SMODEL program for an approximate correction. It is useful for the case where the user cannot obtain any GCPs for an area. Since the geographic coordinates are not very accurate, the user should not expect very accurate results if those points are used.
The CDDIR parameter specifies the directory name which contains the files. See example on how to enter the CDDIR for different operating systems.
The FILE parameter is used to specify the name of the PCIDSK file to hold the imagery and orbital information read off CD. This file is automatically created with the dimensions required to hold all of the requested data. The user should ensure that sufficient disk space is available before CDSPOTC is run. Typically this is about 10 Mbytes per channel requested in parameter CDIC for SPOT multispectral, and about 40 Mbytes for SPOT panchromatic.
Note: Typically there are 3 channels on a SPOT multispectral CD, and there is 1 channel on a SPOT panchromatic CD.
The ORBIT parameter receives the segment number which contains the orbital and attitude information. The orbital and attitude information are required as input to the SMODEL and SORTHO programs. There is no attitude data for georeferenced data.
When CDSPOTC reads the imagery data off the `georeferenced CD', some basic processing is performed to prepare it for orthorectification. Scan lines are left shifted (removing the rough earth rotation correction applied), and all `black' edge pixels are discarded.
PCI wishes to acknowledge the assistance of Dr. Thierry Toutin and Yves Carbonneau at Canada Centre for Remote Sensing for providing source code and assistance of their programs. For more information about the method, please see the following papers:
Toutin, Th, 1985. Analyse mathematique des possibilites cartographiques du systeme SPOT, These de Docteur-Ingenieur en Sciences Geodesiques, ENSG, Paris, France, pp 1-163. Toutin, Th. & Carbonneau Y. La Multi-Stereoscopie Pour Les Corrections D'Images SPOT-HRV, Canadian Journal of Remote Sensing, p110, Vol. 15, No. 2 September, 1989. (This article is also available in English from the Canada Centre for Remote Sensing.)
EASI>CDDIR="/cdrom/SCENE1/" | for UNIX machine EASI>CDDIR="D:\TM\" | for PC EASI>CDDIR="[ABC.SCENE1]" | for VMS machine EASI>FILE="tm.pix" EASI>CDIC=1,3 EASI>TEX1="sherbrooke, CD 1234" EASI>REPORT="sherbrooke.txt" EASI>R CDSPOTCAfter the CD has completed reading, the text report file sherbrooke.txt could be printed using a print utility on your system, and the REPORT parameter should be reset to the terminal:
EASI>REPORT="TERM"The file sherbrooke.pix could now be used as input, along with collected ground control points, to the programs SMODEL and SORTHO.