Data type conversion
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We may change the data type (and radiometric resolution) of a raster layer. | We may change the data type (and radiometric resolution) of a raster layer. | ||
− | # Click the {{button|text=Add raster layer}} [[Image:QGIS_2.0_addrast.png|20px]] and select a multiband raster with data type ''' | + | # Click the {{button|text=Add raster layer}} [[Image:QGIS_2.0_addrast.png|20px]] and select a multiband raster with data type '''UInt16'''. Convert to data type '''uint8 (8bit unsigned integer)''', value range 0 to 255. |
− | + | ||
# In processing toolbar, type {{typed|text=dynamic}} into the search field to find the {{button|text=Orfeo Toolbox --> Image Manipulation --> DynamicConvert}} tool. | # In processing toolbar, type {{typed|text=dynamic}} into the search field to find the {{button|text=Orfeo Toolbox --> Image Manipulation --> DynamicConvert}} tool. | ||
# Open with a double click. Specify the input and a new output file name as shown in the screenshot. | # Open with a double click. Specify the input and a new output file name as shown in the screenshot. | ||
− | # Set High cut | + | # Set High cut quantile and Low cut quantile to {{typed|text=0}} |
+ | # Output min value = '''0''', Output max value = '''255''' | ||
# Click '''Advanced parameters''' and define Output pixel type {{button|text=uint8}}. | # Click '''Advanced parameters''' and define Output pixel type {{button|text=uint8}}. | ||
# Click {{button|text=Run}}. | # Click {{button|text=Run}}. | ||
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[[File:Qgis_rescale.png|400px]] | [[File:Qgis_rescale.png|400px]] | ||
− | The output Image raster is now recoded and saved to unsigned eight bit. | + | The output Image raster is now recoded and saved to unsigned eight bit. Which file size has the input image and the output image? |
[[Category:Working with Raster Data]] | [[Category:Working with Raster Data]] |
Latest revision as of 11:22, 27 October 2021
We may change the data type (and radiometric resolution) of a raster layer.
- Click the Add raster layer and select a multiband raster with data type UInt16. Convert to data type uint8 (8bit unsigned integer), value range 0 to 255.
- In processing toolbar, type dynamic into the search field to find the Orfeo Toolbox --> Image Manipulation --> DynamicConvert tool.
- Open with a double click. Specify the input and a new output file name as shown in the screenshot.
- Set High cut quantile and Low cut quantile to 0
- Output min value = 0, Output max value = 255
- Click Advanced parameters and define Output pixel type uint8.
- Click Run.
The output Image raster is now recoded and saved to unsigned eight bit. Which file size has the input image and the output image?