Automated Cloud Cover Assessment
- Author: B.Bechtel, O.Conrad (c) 2013
- Menu: Imagery | Landsat
Description
Automated Cloud-Cover Assessment (ACCA) for Landsat TM/ETM+ imagery as proposed by Irish (2000). This tool incorporates E.J. Tizado's GRASS GIS implementation (i.landsat.acca).
References
- Irish, R.R. (2000): Landsat 7 Automatic Cloud Cover Assessment. In: Shen, S.S., Descour, M.R. [Eds.]: Algorithms for Multispectral, Hyperspectral, and Ultraspectral Imagery VI. Proceedings of SPIE, 4049: 348-355. doi:10.1117/12.410358.
- Irish, R.R., Barker, J.L., Goward, S.N., Arvidson, T. (2006): Characterization of the Landsat-7 ETM+ Automated Cloud-Cover Assessment (ACCA) Algorithm.. Photogrammetric Engineering and Remote Sensing vol. 72(10): 1179-1188. doi:10.14358/PERS.72.10.1179.
- Tizado, E.J. (2010): GRASS GIS i.landsat.acca. E.J. Tizado's implementation of the method proposed by Irish (2000), Irish et al. (2006). Source Code.
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Green | grid, input | BAND2 | Reflectance | - |
| Red | grid, input | BAND3 | Reflectance | - |
| NIR | grid, input | BAND4 | Reflectance | - |
| SWIR | grid, input | BAND5 | Reflectance | - |
| Thermal | grid, input | BAND6 | Kelvin | - |
| Output | Clouds | grid, output | CLOUD | - | - |
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Grid system | grid system | BAND6_GRIDSYSTEM | - | - |
| SWIR/Thermal Threshold | floating point number | B56C | Threshold for SWIR/Thermal Composite (step 6). | Default: 225.000000 |
| Desert Detection Threshold | floating point number | B45R | Threshold for desert detection (step 10, NIR/SWIR Ratio). | Default: 1.000000 |
| Temperature Histogram | integer number | HIST_N | Number of classes in the cloud temperature histogram. | Minimum: 10
Default: 100 |
| Cloud Signature | boolean | CSIG | Always use cloud signature (step 14). | Default: 1 |
| Cloud Differentiation | boolean | PASS2 | Differentiate between warm (not ambiguous) and cold clouds. | Default: 0 |
| Shadows | boolean | SHADOW | Include a category for cloud shadows. | Default: 1 |
| Filter | boolean | FILTER | Apply post-processing filter to remove small holes. | Default: 1 |
Command Line
Usage: saga_cmd imagery_tools 9 [-BAND2 ] [-BAND3 ] [-BAND4 ] [-BAND5 ] [-BAND6 ] [-CLOUD ] [-B56C ] [-B45R ] [-HIST_N ] [-CSIG ] [-PASS2 ] [-SHADOW ] [-FILTER ]
-BAND2: Green
grid, input
-BAND3: Red
grid, input
-BAND4: NIR
grid, input
-BAND5: SWIR
grid, input
-BAND6: Thermal
grid, input
-CLOUD: Clouds
grid, output
-B56C: SWIR/Thermal Threshold
floating point number
Default: 225.000000
-B45R: Desert Detection Threshold
floating point number
Default: 1.000000
-HIST_N: Temperature Histogram
integer number
Minimum: 10
Default: 100
-CSIG: Cloud Signature
boolean
Default: 1
-PASS2: Cloud Differentiation
boolean
Default: 0
-SHADOW: Shadows
boolean
Default: 1
-FILTER: Filter
boolean
Default: 1