Pansharpening of Sentinel-2 requires defining a 10m reference band because there is no panchromatic band as for Landsat available. The only option is a selection among the 10-m bands (2, 3, 4, or 8) or synthesis (e.g. weighted average of 10-m band). Following the latter approach, the luminance can be calculated from the Blue, Red Green and NIR band to receive a single band grey scale image.
Create a synthesis panchromatic band
- Load the input image
- Open the raster calculator and apply the following formula: Y = 0.20 * NIR(B8) 0.15 * Red(B4) + 0.58 * Green(B3) + 0.07 * Blue(B1)
- Define path and name for the output layer
- Click on the ‘OK-button’.
Create a pan-sharpened layer
- Search for Pansharpening (Bayes) algorithm in the Processing Toolbox.
- Select pseudo-panchromatic band as the Input PAN Image.
- Select the layer contain the original 20m bands as the InputXS Image.
- Specify the directory to save the output file and click on the ‘Run-button’.