Hello,
I have two questions :
1) Is there a way to bin L1B files (spatially / temporally) ? I would like to create daily MODISA files in L1B format.
2) Is there a way to convert the L1B file into netCDF ? Just to read it later with Matlab / Python.
Regards
L1B files : Binning and format
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OB WebDev - norman
- Subject Matter Expert
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L1B files : Binning and format
Since level-1 refers to the storage of radiometer data in sensor-view
coordinates (i.e. scan-line and pixel), it is not possible (by definition) to
combine individual scenes into a daily level-1 file.
You can, however, bin individual scenes and combine them into a
daily level-3 format.
For most of our products, we do not archive L1B, so our software that generates
L1B still produces HDF4 instead of the NetCDF4 that we now store our archive
products in. I imagine that there are Matlab or Python utilities that read HDF4.
Regards,
Norman
coordinates (i.e. scan-line and pixel), it is not possible (by definition) to
combine individual scenes into a daily level-1 file.
You can, however, bin individual scenes and combine them into a
daily level-3 format.
For most of our products, we do not archive L1B, so our software that generates
L1B still produces HDF4 instead of the NetCDF4 that we now store our archive
products in. I imagine that there are Matlab or Python utilities that read HDF4.
Regards,
Norman
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OB.DAACx - SeanBailey
- Posts: 1519
- Joined: Wed Sep 18, 2019 6:15 pm America/New_York
- Been thanked: 9 times
L1B files : Binning and format
If your purpose is to have a gridded TOA dataset, you could use l2gen to output Lt, which can then be binned/mapped. As Norman points out, it will no longer be "L1B", but L3.
Here's how it can be done:
The output of the l2gen example above would be a reasonably equivalent netCDF4 version of the L1B that could easily be read by tools that read netCDF.
Sean
Here's how it can be done:
l2gen ifile=<MODIS L1B> geofile=<MODIS GEO> ofile=<L2 filename> atmocor=0 gain=[1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0] l2prod=Lt_nnn
l2bin ifile=<L2_files.txt> ofile=<Daily L3b> flaguse=ATMFAIL
l3mpagen ifile=<Daily L3b> ofile=<Daily L3m>
The output of the l2gen example above would be a reasonably equivalent netCDF4 version of the L1B that could easily be read by tools that read netCDF.
Sean