Direct Broadcast Flat File Output File Format ---------------------------------------------- The IMAPP MODIS flat file software reads in the MODIS L1B files and converts them to flat binary image format following the ENVI standard (.img and .hdr files). These FORTRAN routines create binary flat files and header files in ENVI readable format from input L1B 1km, 500m, 250m, geolocation MODIS Direct Broadcast or DAAC formatted HDF files. The binary files can then be used as input for IMAPP MODIS direct broadcast Level 2 products. The software will extract the data into either radiances or reflectances (normalized radiances - values not divided by the cosine of the solar zenith angle). The routines and how to execute them follow: Routine Name Input Platform Output data ----------- ---------- -------- ----------- modis_extract_1km.exe L1b 1km hdf file SatName 1km flat file and header file modis_extract_met.exe L1b 1km hdf file SatName Scan based meta file and header file modis_extract_hkm.exe L1b 500m hdf file SatName 500m flat file and header file modis_extract_qkm.exe L1b 250m hdf file SatName 250m flat file and header file modis_extract_geo.exe L1b geo. hdf file SatName Geolocation flat file and header file Because the files are created following the ENVI header format, these files can be viewed and compared using ITT's ENVI tool (http://www.ittvis.com/envi/) or its free counterpart tool freelook, which can be downloaded from: http://www.ittvis.com/download/download.asp ------------------------------------------------------------------------- The flatfile output products consist of separate .img files in flat binary format, and accompanying header file. modis_extract_1km.exe will create an output file with the 1000m.img extension from the input L1B 1 km file (either a1*1000m.hdf or t1*1000m.hdf files) containing 36 float band interleaved values at 1km pixel resolution. Please see a list of these bands below. The test output file that you create from the input test data set contains the nominal MODIS swath size 1354 and 2890 lines. Therefore, the product a1.07066.2038.1000m.img file is 1354 elements, by 36 bands, by 2890 lines. In FORTRAN and IDL, it would be read as an array(1354,36,2890). This would be reversed in C - array(2890,36,1354). 1 Kilometer - 1000m.img file format ---------------------------- Four byte float data 36 bands 1km-pixel resolution Band Interleaved fill value = -1.00 MODIS bands = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36} band units = {ref,ref,ref,ref,ref,ref,ref,ref,ref,ref,ref,ref,ref,ref, ref,ref,ref,ref,ref,rad,rad,rad,rad,rad,rad,ref,rad,rad,rad,rad, rad,rad,rad,rad,rad,rad} Where rad = Radiance units in Watts per square meter per steradian per micron ref = reflectance - normalized radiance, not divided by the cosine of the solar zenith angle -------------------------------------------------------------------------- modis_extract_hkm.exe will create an output file with the 500m.img extension from the input L1B 500 m file (either a1*500m.hdf or t1*500m.hdf files) containing 7 float band interleaved values at 500 m pixel resolution. Please see a list of these bands below. The test output file that you create from the input test data set contains the nominal MODIS swath size 2708 and 5780 lines. Therefore, the product a1.07066.2038.500m.img file is 2708 elements, by 7 bands, by 5780 lines. In FORTRAN and IDL, it would be read as an array(2708,7,5780). This would be reversed in C - array(5780,7,2708). This file will be produced in daytime files only. 500 Meter - 500m.img file format ---------------------------- Four byte float data 7 bands 500m-pixel resolution Band Interleaved fill value = -1.00 MODIS bands = { 1, 2, 3, 4, 5, 6, 7} band units = {ref,ref,ref,ref,ref,ref,ref} Where ref = reflectance - normalized radiance, not divided by the cosine of the solar zenith angle -------------------------------------------------------------------------- modis_extract_qkm.exe will create an output file with the 250m.img extension from the input L1B 250 m file (either a1*250m.hdf or t1*250m.hdf files) containing 2 float band interleaved values at 250 m pixel resolution. Please see a list of these bands below. The test output file that you create from the input test data set contains the nominal MODIS swath size 5416 and 11560 lines. Therefore, the product a1.07066.2038.250m.img file is 5416 elements, by 2 bands, by 11560 lines. In FORTRAN and IDL, it would be read as an array(5416,2,11560). This would be reversed in C - array(11560,2,5416). This file will be produced in daytime files only. 250 Meter - 250m.img file format ---------------------------- Four byte float data 2 bands 250m-pixel resolution Band Interleaved fill value = -1.00 MODIS bands = { 1, 2} band units = {ref,ref} Where ref = reflectance - normalized radiance, not divided by the cosine of the solar zenith angle -------------------------------------------------------------------------- modis_extract_geo.exe will create an output file with the geo.img extension from the input L1B Geolocation file (either a1*geo.hdf or t1*geo.hdf files) containing 8 float band interleaved values at 1 km pixel resolution. Please see a list of these bands below. The test output file that you create from the input test data set contains the nominal MODIS swath size 1354 and 2890 lines. Therefore, the product a1.07066.2038.geo.img file is 1354 elements, by 8 bands, by 2890 lines. In FORTRAN and IDL, it would be read as an array(1354,8,2890). This would be reversed in C - array(2890,8,1354). This file will be produced in daytime files only. Geolocation - geo.img file format ------------------------------------ Four byte float data 8 bands 1 km-pixel resolution Band Interleaved fill value = -999.00 Geolocation band names = {Latitude, Longitude, SensorZenith, SensorAzimuth, SolarZenith, SolarAzimuth, Elevation, LandSea} band units = {degree,degree,degree,degree,degree,degree,meters,N/A}