The MODIS LDOPE software tools were developed by Sadashiva Devadiga, Yi Zhang
and David Roy at the LDOPE
facility, NASA Goddard Space Flight Center, to assist with the analysis and quality assessment of the MODIS Land (MODLAND) products.The tools have been developed with feedback from the MODLAND science team and incorporate the scientific knowledge, experience and insights gained during the substantial MODLAND product development period. These software tools are invoked as stand-alone executables from a command-line interface. The software is supported on Irix, Solaris, Linux, and Windows operating systems. Although there are no distribution or re-use constraints associated with this software, developers using or modifying this software should credit the original authorship of these tools.
Drop 3
Tool Name
Description
comp_sds_hist
Print the histogram of SDS values (frequency and values), excluding no-data and missing values, of specified SDSs in any MODIS Land HDF-EOS data product.
comp_sds_range
Print the observed range, excluding no-data and missing values, of specified SDSs in a MODIS Land HDF-EOS data product.
comp_sds_stat
Print summary statistics (mean, standard deviation, minimum, maximum and number of observations) of any SDS, excluding no-data and missing values, of a MODIS Land HDF-EOS data product.
comp_sds_values
Print the unique values found in specified SDSs of a MODIS Land HDF-EOS data product. This tool is most useful for summarizing the data distribution of SDSs that have only a small number of values (e.g., the MODIS Land HDF-EOS snow and fire products).
convert_l1b_data
Convert MODIS L1B data to Top of Atmosphere (TOA) reflectance for the MODIS reflective bands and TOA radiance for the MODIS emissive bands and write these to 2D HDF SDS(s) that can be read by commercial of the shelf (COTS) software. The conversion is performed using the scale and off-sets defined in the MODIS L1B product metadata.
create_mask
Apply relational and logical operators to one or more SDS in one or more MODIS Land HDF-EOS data products to create an output 2D HDF SDS that can be read by conventional COTS. For example, create a binary SDS that shows the pixel locations where only good quality, non-cloudy, 16-day vegetation index values with a land cover type = 3 are present.
create_sds_ts_stat
Create a summary statistic HDF file containing one or more output 2D SDS that describe the mean, standard deviation, minimum, maximum, sum, and number of observations, computed on pixel wise basis from a time series of input MODIS Land HDF-EOS data products.
geolocation
Compute the geographic latitude and longitude of a MODIS Land L2G/L3/L4 pixel coordinate.
math_sds
Perform simple arithmetic on two input SDSs of the same or different MODIS Land HDF-EOS data products and output the results to a 2D SDS.
read_sds_attributes
Print the attributes of one or more SDS of MODIS Land HDF-EOS data products.
subset_sds
Create spatial subset SDS(s) from one or more SDS of a MODIS Land HDF-EOS data product.
tile_id
Compute the MODIS Land L2G/L3/L4 tile id for a given latitude and longitude. This tool identifies the MODIS Land tile that corresponds to a known geographic location.
transpose_sds
Transpose one or more SDS in a MODIS Land HDF-EOS data product by rotating the SDS 180 degree in clockwise direction This tool enables qualitative comparison of MODIS Aqua and Terra Level 2 or Level 1 granules.
unpack_sds_bits
The MODIS Land HDF-EOS data product per-pixel QA information and other information such as the land-sea mask, logical criteria used by the algorithm, and cloud state are stored in an efficient bit encoded manner. This tool decodes requested bit fields and writes them to 2D HDF SDSs that can be read by conventional COTS.
Drop 2
Tool Name
Description
cp_proj_param
Copy projection metadata into an HDF file that is defined in the MODLAND Integerized Sinusoidal projection or Sinusoidal projection. The HDF file may then be reprojected using the LP DAAC reprojection tool. This allows reprojection of MODLAND product SDS(s) filtered or masked by LDOPE QA tools or other software.
mask_sds
Mask one of more SDS of a MODLAND product file and output the SDS values at pixels where the mask criteria are met and output fill values elsewhere.
read_pixvals
Read MODLAND product values at specified pixel locations.
read_proj_param
Read the projection parameter information of a L2G/L3/L4 MODLAND HDF-EOS product. This information is needed to project non-MODLAND data into registration with a geolocated MODLAND product.
Drop 1
Tool Name
Description
enlarge_sds
The inverse of companion tool reduce_sds. Simulate finer resolution data by pixel replication.
mosaic_sds
Create a spatial mosaic of SDSs from different L3 MODLAND products. Specified SDSs are spatially arranged based either on their geolocation or in a user specified manner.
read_meta
Print the ECS core and archive metadata and SDS attributes of any MODLAND product.
read_l2g
The MODLAND L2G products store one or more L2 observations for each L2G pixel in a series of layers (that reflect the MODIS orbit overpass and swath sensing geometry) in a compressed run length encoded format. This tool reads the L2G format and writes user specified layers to output 2D HDF Science Data Sets (SDSs) that can be read by conventional commercial off the shelf software (COTS).
reduce_sds
Generate reduced spatial resolution MODLAND product SDSs by sub-sampling or averaging. Handle the MODLAND product no-data and missing values. This may be used to reduce data volumes, and to quickly enable analysis of the different MODLAND product spatial resolutions (250m, 500m, 1km), or to enable comparison with other coarser spatial resolution data sets.
reduce_sds_rank
Several MODLAND products (e.g., MOD43) and related MODIS products (e.g., MOD35) contain multidimensional SDSs. This tool converts multidimensional (3D or 4D) SDS to a series of 2D HDF SDSs that can be read by conventional COTS.
sds2bin
Convert an SDS of any HDF-EOS file to a flat binary image format.
unpack_sds_bits
The MODLAND product per-pixel QA information and other information such as the land-sea mask, logical criteria used by the algorithm, and cloud state are stored in an efficient bit encoded manner. This tool decodes requested bit fields and writes them to 2D HDF SDSs that can be read by conventional COTS.
