QGIS Basic

[@ousmanealamakaba3135]

thank you sir for everything . i always enjoy watching your amazing tuto to learn more about QGIS

[@sedighepaghe7979]

thank you for this tutorial, how can I add an alpha band from a dem file to a geotiff file format ?

[@HalHartQGIS]

Are you trying create an overlay, or completely change the file type to geotiff

[@HalHartQGIS]

I will have to look into it to see about a single band conversion, but I do know there are many DEM to GEOtiff converters like this one: mygeodata.cloud/converter/usgsdem-to-geotiff

[@sedighepaghe7979]

Thank you for your reply, actually I want to detect some area in an image using a dem file. At first I thought maybe I should combine them but in this case I would not have the pixel value of a cell and its elevation separately. Now I find if I compare two images and define threshold maybe maybe I can extract these pixels with the defined elevation range, but as I am new in matlab I have problem with coding. I would be grateful if I know your comment about this case.

[@HalHartQGIS]

Ok so you now you are seeing it more clearly you don't need extract the alpha band you just need to pull and identify the elevations you want. So you now have many options for this. For this I would use the paletted/unique values since you are looking for specific elevations. you can duplicate the layers you are working on and experiment with this render type. Go to layer properties > symbology> select render type paletted. I think I did a video on this ill check if so ill post it here.

[@HalHartQGIS]

Yep I did here is the link: kzbin.info/www/bejne/hnnYk39tgpmpga8

[@allanpauyo2993]

Where can i get dem file

[@HalHartQGIS]

www.maris.state.ms.us/JacksonDOQQ/ I used clintne,clintnw,clintse,clintsw