How to make band composite image in QGIS

I am wondering how I can make a band composite from three large bands files from Landsat? I was using option Raster>Miscellaneous>Merge but when I try to do it it crashes.

Answer

This is something you can achieve with a Virtual Raster (Catalog). This will create a metadata file (.vrt) that QGIS treats like a merged multi-band raster without having to merge all the bands.

1. Raster --> Misc. --> Build Virtual Raster


2. Select the bands you want to use as "Input files"


3. Check "Separate" to put each input file into a single band (otherwise they will be merged spatially and all put into a single band)


4. Open the Virtual Raster (.vrt) in QGIS and treat it like a merged composite

Here is an example using a Landsat 8 scene of the Alps to create a band 7,5,2 false color composite. Creation of the Virtual Raster (urban-fcc.vrt) takes seconds and the file is 3KB in size.