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i.modis.qc - Extracts quality control parameters from MODIS QC layers.


imagery, imagery quality assessment, reflectance, land surface temperature, vegetation, MODIS


i.modis.qc --help
i.modis.qc input=name output=name productname=string qcname=string [band=string] [--overwrite] [--help] [--verbose] [--quiet] [--ui]


Allow output files to overwrite existing files
Print usage summary
Verbose module output
Quiet module output
Force launching GUI dialog


input=name [required]
Name of input surface reflectance QC layer [bit array]
output=name [required]
Name for output QC type classification layer
productname=string [required]
Name of MODIS product type
Options: mod09Q1, mod09A1, mod09A1s, mod09CMG, mod09CMGs, mod09CMGi, mod11A1, mod11A2, mod13A2, mcd43B2, mcd43B2q
Default: mod13A2
mod09Q1: surf. refl. 250m 8-days
mod09A1: surf. refl. 500m 8-days
mod09A1s: surf. refl. 500m 8-days, State QA
mod09CMG: surf. refl. 5000m daily
mod09CMGs: surf. refl. 5000m daily, State QA
mod09CMGi: surf. refl. 5000m daily, Internal Climatology
mod11A1: LST 1km daily (Day/Night)
mod11A2: LST 1km 8-days (Day/Night)
mod13A2: VI 1km 16-days
mcd43B2: Brdf-Albedo Quality (Ancillary SDS) 1km 8-days
mcd43B2q: Brdf-Albedo Quality (BRDF SDS) 1km 8-days
qcname=string [required]
Name of QC type to extract
Options: adjcorr, atcorr, cloud, data_quality, diff_orbit_from_500m, modland_qa, mandatory_qa_11A1, data_quality_flag_11A1, emis_error_11A1, lst_error_11A1, data_quality_flag_11A2, emis_error_11A2, mandatory_qa_11A2, lst_error_11A2, aerosol_quantity, brdf_correction_performed, cirrus_detected, cloud_shadow, cloud_state, internal_cloud_algorithm, internal_fire_algorithm, internal_snow_mask, land_water, mod35_snow_ice, pixel_adjacent_to_cloud, icm_cloudy, icm_clear, icm_high_clouds, icm_low_clouds, icm_snow, icm_fire, icm_sun_glint, icm_dust, icm_cloud_shadow, icm_pixel_is_adjacent_to_cloud, icm_cirrus, icm_pan_flag, icm_criteria_for_aerosol_retrieval, icm_aot_has_clim_val, modland_qa, vi_usefulness, aerosol_quantity, pixel_adjacent_to_cloud, brdf_correction_performed, mixed_clouds, land_water, possible_snow_ice, possible_shadow, platform, land_water, sun_z_angle_at_local_noon, brdf_correction_performed
Default: modland_qa
adjcorr: mod09: Adjacency Correction
atcorr: mod09: Atmospheric Correction
cloud: mod09: Cloud State
data_quality: mod09: Band-Wise Data Quality Flag
diff_orbit_from_500m: mod09: 250m Band is at Different Orbit than 500m
modland_qa: mod13A2: MODIS Land General Quality Assessment
mandatory_qa_11A1: mod11A1: MODIS Land General Quality Assessment
data_quality_flag_11A1: mod11A1: Detailed Quality Indications
emis_error_11A1: mod11A1: Average Emissivity Error Classes
lst_error_11A1: mod11A1: Average LST Error Classes
data_quality_flag_11A2: mod11A2: Detailed Quality Indications
emis_error_11A2: mod11A2: Average Emissivity Error Classes
mandatory_qa_11A2: mod11A2: MODIS Land General Quality Assessment
lst_error_11A2: mod11A2: Average LST Error Classes
aerosol_quantity: mod13A2: Quantity range of Aerosol
brdf_correction_performed: mcd43B2q: Quality of BRDF correction performed
cirrus_detected: mod09*s: StateQA Cirrus Detected
cloud_shadow: mod09*s: StateQA Cloud Shadow
cloud_state: mod09*s: StateQA Cloud State
internal_cloud_algorithm: mod09*s: StateQA Internal Cloud Algorithm
internal_fire_algorithm: mod09*s: StateQA Internal Fire Algorithm
internal_snow_mask: mod09*s: StateQA Internal Snow Mask
land_water: mcd43B2: Quality of BRDF correction performed
mod35_snow_ice: mod09*s: StateQA mod35 Snow Ice
pixel_adjacent_to_cloud: mod13A2: if pixel is a cloud neighbour
icm_cloudy: mod09*i: Internal CM: Cloudy
icm_clear: mod09*i: Internal CM: Clear
icm_high_clouds: mod09*i: Internal CM: High Clouds
icm_low_clouds: mod09*i: Internal CM: Low Clouds
icm_snow: mod09*i: Internal CM: Snow
icm_fire: mod09*i: Internal CM: Fire
icm_sun_glint: mod09*i: Internal CM: Sun Glint
icm_dust: mod09*i: Internal CM: Dust
icm_cloud_shadow: mod09*i: Internal CM: Cloud Shadow
icm_pixel_is_adjacent_to_cloud: mod09*i: Internal CM: Pixel is Adjacent to Cloud
icm_cirrus: mod09*i: Internal CM: Cirrus
icm_pan_flag: mod09*i: Internal CM: Pan Flag
icm_criteria_for_aerosol_retrieval: mod09*i: Internal CM: Criteria for Aerosol Retrieval
icm_aot_has_clim_val: mod09*i: Internal CM: AOT (aerosol optical depth) has clim. val.
vi_usefulness: mod13A2: Quality estimation of the pixel
mixed_clouds: mod13A2: if pixel mixed with clouds
possible_snow_ice: mod13A2: if snow/ice present in pixel
possible_shadow: mod13A2: if shadow is present in pixel
platform: mcd43B2: Quality of BRDF correction performed
sun_z_angle_at_local_noon: mcd43B2: Quality of BRDF correction performed
Band number of MODIS product (mod09Q1=[1,2],mod09A1=[1-7],m[o/y]d09CMG=[1-7], mcd43B2q=[1-7])
Options: 1, 2, 3, 4, 5, 6, 7
1: Band 1: Red
2: Band 2: NIR
3: Band 3: Blue
4: Band 4: Green
5: Band 5: SWIR 1
6: Band 6: SWIR 2
7: Band 7: SWIR 3

Table of contents


i.modis.qc extracts Requested Quality Assessment flags from the following MODIS products: MOD09A1, MOD09Q1, MOD11A1, MOD11A2, MOD13A2, MCD43B2. This does include MOD09A1 QA_state_500m layer (see Notes).
MOD09A1/Q1: MODLAND QA Bits. bits=[0-1]
MOD09Q1: Cloud State. bits=[2-3] 
MOD09Q1: Band-wise Data Quality 250m bits=[4-7][8-11]
MOD09A1: Band-wise Data Quality 500m bits=[2-5][6-9][10-13][14-17][18-21][22-25][26-29]
MOD09A1/Q1: Atmospheric correction bit=[12]/[30]
MOD09A1/Q1: Adjacency correction bit=[13]/[31]
MOD09Q1: Different orbit from 500m product, bit=[14]
MOD11A1: Mandatory QA Flags bits=[0-1]
MOD11A1: Data Quality Flag bits=[2-3]
MOD11A1: Emis Error Flag bits=[4-5]
MOD11A1: LST Error Flag bits=[6-7]

MOD11A2: Mandatory QA Flags bits=[0-1]
MOD11A2: Data Quality Flag bits=[2-3]
MOD11A2: Emis Error Flag bits=[4-5]
MOD11A2: LST Error Flag bits=[6-7]
MOD09A1s: Cloud State bits=[0-1]
MOD09A1s: Cloud shadow bits=[2]
MOD09A1s: Land/Water Flag bits=[3-5]
MOD09A1s: Aerosol Quantity bits=[6-7]
MOD09A1s: Cirrus detected bits=[8-9]
MOD09A1s: Internal Cloud Algorithm Flag bits=[10]
MOD09A1s: Internal Fire Algorithm Flag bits=[11]
MOD09A1s: MOD35 snow/ice flag bits=[12]
MOD09A1s: Pixel adjacent to cloud bits=[13]
MOD09A1s: BRDF correction performed bits=[14]
MOD09A1s: Internal Snow Mask bits=[15]
MOD13A2: Mandatory QA Flags 1km bits[0-1]
MOD13A2: VI Usefulness Flag bits[2-5]
MOD13A2: Aerosol quantity Flags 1km bits[6-7]
MOD13A2: Adjacent cloud detected 1km bit[8]
MOD13A2: Atmosphere BRDF correction performed 1km bit[9]
MOD13A2: Mixed clouds 1km bit[10]
MOD13A2: Land/Water Flags 1km bits[11-13]
MOD13A2: Possible Snow/Ice 1km bits[14]
MOD13A2: Possible Shadow 1km bits[15]
MCD43B2: Albedo Quality Ancillary Platform Data 1km bits[0-3]
SDS: BRDF_Albedo_Ancillary
MCD43B2: Albedo Quality Ancillary Land/Water Data 1km bits[4-7]
SDS: BRDF_Albedo_Ancillary
MCD43B2: Albedo Quality Ancillary Sun Zenith Angle at Local Solar Noon Data 1km bits[8-14]
SDS: BRDF_Albedo_Ancillary
MCD43B2: Band-wise Albedo Quality Data 1km
SDS: BRDF_Albedo_Band_Quality


In MOD09A1: It seems that cloud related info is not filled properly in the standard QC (MOD09A1 in this module) since version 3, State-QA 500m images (MOD09A1s in this module) should be used (see Vermote et al., 2008).


Add more daily products.




Yann Chemin

Last changed: $Date: 2014-12-11 15:16:30 -0800 (Thu, 11 Dec 2014) $


Available at: i.modis.qc source code (history)

Note: A new GRASS GIS stable version has been released: GRASS GIS 7.4, available here.
Updated manual page: here

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