I was able to use MapTiler for converting a single raster (ortofoto GeoTIFF obtained with UAV) into a KML file. Now I want to convert a RGB Landsat into KML for visualisation in Google Earth. It is not clear to me how this can be done as the raster has three bands now. In addition, how I can assure that the nice visualisation of the LANDSAT in QGIS, obtained after setting manually min/max values with'Colourmap', is maintained during conversion MapTiler?
If you assign your own colormap and min/max values in QGIS - to change the visual look of the image - you have to export the changes from QGIS - and save the file as normal GeoTIFF with RGB palette and 8 bits.
The next step would be then to create the tiles with MapTiler (http://www.maptiler.com/).