Co-registration with SNAP
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(Difference between revisions)
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= Convert data type from float32 to uint8 = | = Convert data type from float32 to uint8 = | ||
* {{mitem|text=Raster --> Data Conversion --> Convert Datatype}} | * {{mitem|text=Raster --> Data Conversion --> Convert Datatype}} | ||
| − | * Check '''Save as''' and select GeoTIFF from drop downlist | + | * Check '''Save as''' and select GeoTIFF from drop downlist. |
| + | * Target Data type: '''uint8''' | ||
| + | * Scaling: '''Linear (slope and intercept)''' | ||
[[File:snap_datatype_io.png|400px]] [[File:snap_datatype_params.png|400px]] | [[File:snap_datatype_io.png|400px]] [[File:snap_datatype_params.png|400px]] | ||
* Mark the coregistered image {{typed|collocate_cnv}} in ToC. Right click {{mitem|text= Open RGB Image Window --> OK}}. Check the geometric quality of the co-registration comparing {{typed|text=clip_ebee_ortho_align.tif}} (bottom), {{typed|text=clip_ebee_ortho_align.tif}} (middle) and {{typed|text=collocate_cnv.tif}} (top). | * Mark the coregistered image {{typed|collocate_cnv}} in ToC. Right click {{mitem|text= Open RGB Image Window --> OK}}. Check the geometric quality of the co-registration comparing {{typed|text=clip_ebee_ortho_align.tif}} (bottom), {{typed|text=clip_ebee_ortho_align.tif}} (middle) and {{typed|text=collocate_cnv.tif}} (top). | ||
Revision as of 13:14, 9 November 2020
Contents |
Visualize geometric offset
- Start SNAP Desktop
- File --> Open Product.... Browse for Unmanned Aerial System (UAS) ortho mosaics:
\geodata\uas\clip_ebee_ortho_align.tif is a reference image which is very well georeferenced. \geodata\uas\clip_mavic_ortho_align.tif is an image with a positional offset. It needs to be registered to the reference image. Open or drag and drop marked files from Windows File Explorer into the SNAP Product Explorer tab.
- Mark the reference image clip_ebee_ortho_align.tif in ToC. Right click Open RGB Image Window --> OK.
- Mark the image to be registered clip_mavic_ortho_align.tif in ToC. Right click Open RGB Image Window --> OK.
- Window --> Tile Vertically. Both side-by-side windows are spatially linked. Zoom in and use the Panning tool to see the offset between both images
Split multiband to single band files
- Mark the image to be registered clip_mavic_ortho_align.tif in ToC. Raster --> Subset --> Band Subset. Check exclusivly band_1.
- Repeat this step for band_2 and band_3 creating separated single bands of the image to be registered .
Co-registration of single band raster files
- Raster --> Geometric operations --> GeFolki Co-registration.
- Define I/O Parameters and Processing Parameters:
- Click Run.
- Repeat this step for band_2 (subset_1) and band_3 (subset_2). Adjust processing parameters for each band, accordingly.
Stack single bands to multiband file
- Create a stack of all coregistered single bands. Raster --> Geometric operations --> Collocation
Convert data type from float32 to uint8
- Raster --> Data Conversion --> Convert Datatype
- Check Save as and select GeoTIFF from drop downlist.
- Target Data type: uint8
- Scaling: Linear (slope and intercept)
- Mark the coregistered image {{{text}}} in ToC. Right click Open RGB Image Window --> OK. Check the geometric quality of the co-registration comparing clip_ebee_ortho_align.tif (bottom), clip_ebee_ortho_align.tif (middle) and collocate_cnv.tif (top).
