l1aextract_seawifs | ![]() |
Creates an extracted L1A SeaWiFS file.
Location
Details
Command Line Usage
Tools -> OCSSW Processing -> l1aextract_seawifs
l1aextract_seawifs is used to create a sub-scene file by extracting and/or sub-sampling from an original SeaWiFS L1A file. The output file is an HDF file and has the same format as the original L1A file.
The l1aextract_seawifs GUI allows the user to specify either the pixel/line ranges, the lat/lon ranges, or the two lat/lon corner points for the subscene to be extracted.
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UI Element Name | Type | Description | Required/Optional | Default Value |
infile | Text Field | Input MODIS Aqua or Terra L1A file to be extracted, or an L1A filelist for multiple file extraction. (Required) | Required | |
ofile | Text Field | Output filename for the L1A extracted subscene. A default ofile name is generated by the program. | Required | |
swlon | Text Field | Longitude of southwest corner of the box to be extracted. | Conditional | |
swlat | Text Field | Latitude of southwest corner of the box to be extracted. | Conditional | |
nelon | Text Field | Longitude of northeast corner of the box to be extracted. | Conditional | |
nelat | Text Field | Latitude of northeast corner of the box to be extracted. | Conditional | |
spix | Text Field | Starting pixel in infile for extracting. | Conditional | |
epix | Text Field | Ending pixel in infile for extracting. | Conditional | |
sscan | Text Field | Starting line in infile for extracting. | Conditional | |
escan | Text Field | Ending line in infile for extracting. | Conditional | |
pix_sub | Text Field | Pixel sub-sampling rate. | Optional | |
sc_sub | Text Field | Scan line sub-sampling rate. | Optional |
UI Element Name | Type | Description |
Browser Button | Button | Selects infile/ofile |
Compute PixLines from LonLat | Button | Derives spixl, epixl, sline, and eline arguments from swlon, swlat, nelon, and nelat arguments by internally executing the lonlat2pixline program. |
Load Parameters ... | Button | Reads in previously saved parameters and populates the fields in GUI. |
Store Parameters ... | Button | Saves the current arguments in GUI in a file. |
Run | Button | Executes the l1aextract_seawifs command with arguments provided in the UI. |
Cancel | Button | Closes current processor GUI. |
Apply | Button | Makes current arguments effective. |
Open in SeaDAS | Checkbox | If selected, the ofile will be added to the open products list right after its generation. |
? | Button | Displays the help content of the current command. |
Usage: l1aextract_seawifs infile spix epix sscan escan pix_sub sc_sub outfile where: infile - input l1a data HDF file spix - start pixel number epix - end pixel number sscan - start scan line escan - end scan line pix_sub - pixel subsampling rate sc_sub - scan line subsampling rate outfile - output file name NOTE: Start and End pixel/scanline will be set to input file's nsamp and nrec respectively, if, the given values are out of range