Tool Automated Cloud Cover Assessment
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.
- Author: B.Bechtel, O.Conrad (c) 2013
- Menu: Imagery|Landsat
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 | B56C | Threshold for SWIR/Thermal Composite (step 6). | Default: 225.000000 |
| Desert Detection Threshold | Floating point | B45R | Threshold for desert detection (step 10, NIR/SWIR Ratio). | Default: 1.000000 |
| Temperature Histogram | Integer | 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 <str>] [-BAND3 <str>] [-BAND4 <str>] [-BAND5 <str>] [-BAND6 <str>] [-CLOUD <str>] [-B56C <double>] [-B45R <double>] [-HIST_N <num>] [-CSIG <str>] [-PASS2 <str>] [-SHADOW <str>] [-FILTER <str>]
-BAND2:<str> Green
Grid, input
-BAND3:<str> Red
Grid, input
-BAND4:<str> NIR
Grid, input
-BAND5:<str> SWIR
Grid, input
-BAND6:<str> Thermal
Grid, input
-CLOUD:<str> Clouds
Grid, output
-B56C:<double> SWIR/Thermal Threshold
Floating point
Default: 225.000000
-B45R:<double> Desert Detection Threshold
Floating point
Default: 1.000000
-HIST_N:<num> Temperature Histogram
Integer
Minimum: 10
Default: 100
-CSIG:<str> Cloud Signature
Boolean
Default: 1
-PASS2:<str> Cloud Differentiation
Boolean
Default: 0
-SHADOW:<str> Shadows
Boolean
Default: 1
-FILTER:<str> Filter
Boolean
Default: 1