program - l2extract

l2extract

Description: This program is used to create subscene files by extracting from SeaDAS created L2 files (SeaWiFS, MODIS, CZCS, OCTS). The output files are HDF files and have the same format as the original L2 files. The interactive mode or command mode allows users to specify either pixel/line ranges or lat/lon ranges for a subscene to be extracted. Input L2 file(s) can be either a single HDF file or a file list which contains multiple filenames for extracting multiple files at once.

[Command Mode][Interactive Mode]

Command Mode

Usage: (extraction based on pixel/line ranges)
l2extract, ifile, ofile, spix, epix, slin, elin, help=hlp

OR: (extraction based on lat/lon ranges)
l2extract, ifile, ofile, slat, elat, slon, elon, ofile

Arguments/Keywords:

ifile Input SeaDAS created L2 files (MODIS, SeaWiFS, CZCS, OCTS, and MODIS high resolution). 'ifile' can be a file list containing mutiple filenames for extracting multiple files at once.

spix Starting pixel in ifile for extracting.

epix Ending pixel in ifile for extracting.

slin Starting line in ifile for extracting.

elin Ending line in ifile for extracting.

slat
Starting latitude boundary (North) that defines the area to be extracted.

elat
Ending latitude boundary (South) that defines the area to be extracted.

slon
Starting longitude boundary(West) that defines the area to be extracted.

elon
Ending longitude boundary (East) that defines the area to be extracted.

ofile The output HDF file name for the extracted subscene (only used for single file extraction; multiple file extraction function will use SeaDAS default file name format).

help To list all arguments and keywords available for this program.

Examples:

(1) l2extract, ifile='A2006209184510.L2_qkm', ofile='A2006209184510_qkm.sub', slat=31, elat=28, slon=-85, elon=-83

(2) l2extract, ifile='A2006209184510.L2_qkm', ofile='A2006209184510_qkm2.sub', sline=1257, eline=1859, spixl=1260, epixl=2692

(3) l2extract, ifile='filelist.txt', slat=31, elat=25, slon=-82, elon=-78

Where file 'filelist.txt' has multiple file names like:

A2006076182500.L2_LAC
A2006076182501.L2_LAC
A2006076182502.L2_LAC

Interactive Mode:

The L2 extraction window can be accessed by selecting "l2extract" from the Process pull down menu in the SeaDAS main menu or from the command mode by typing: "l2extract".

Action Items:

Input file The input SeaDAS created L2 HDF file or a text file contains multiple L2 filenames.

Output file
The output HDF file name for the extracted subscene (only used for single file extraction; multiple file extraction function will use SeaDAS default file name format).

Select To display the File Selection Widget for selecting the input/output HDF file for extraction processing.

Run
Starts the file extract program.

Run(BG)
Runs the extraction process in the background.

Help
Reach Help info (this page)

Quit To close the window.

Curator: OceanColor Webmaster

Authorized by: gene carl feldman

ifile	Input SeaDAS created L2 files (MODIS, SeaWiFS, CZCS, OCTS, and MODIS high resolution). 'ifile' can be a file list containing mutiple filenames for extracting multiple files at once.
spix	Starting pixel in ifile for extracting.
epix	Ending pixel in ifile for extracting.
slin	Starting line in ifile for extracting.
elin	Ending line in ifile for extracting.
slat	Starting latitude boundary (North) that defines the area to be extracted.
elat	Ending latitude boundary (South) that defines the area to be extracted.
slon	Starting longitude boundary(West) that defines the area to be extracted.
elon	Ending longitude boundary (East) that defines the area to be extracted.
ofile	The output HDF file name for the extracted subscene (only used for single file extraction; multiple file extraction function will use SeaDAS default file name format).
help	To list all arguments and keywords available for this program.

Input file	The input SeaDAS created L2 HDF file or a text file contains multiple L2 filenames.
Output file	The output HDF file name for the extracted subscene (only used for single file extraction; multiple file extraction function will use SeaDAS default file name format).
Select	To display the *File Selection Widget* for selecting the input/output HDF file for extraction processing.
Run	Starts the file extract program.
Run(BG)	Runs the extraction process in the background.
Help	Reach Help info (this page)
Quit	To close the window.