Selecting groups of files and iterating composite raster

Question

I have a query regarding the best way to process the multispectral data I requested to be collected for my MSc study site.

The data I am working with has been saved as single band tiffs, rather than as multiband ones. They are named as follows.

1454327096.tif = Green band 1454327096_1.tif = Red band 1454327096_2.tif = Red_edge band 1454327096_3.tif = NIR band

I have about 1084 of these images so I would like to find some way of automating the process of compositing the bands.

My thought was to use an iterator in modelbuilder in ArcGIS. However I have no idea how to get the iterator to group files together and only composite the ones where the file names are the same.

Answer 1

If they're all in one folder, you can probably use a combination os.walk or os.listdir and fnmatch (wildcard) in a python script such as below.

rootDir = "folder path to files"
outDir = "output directory
outName = "Output File Name"
search = "wildcard, whatever is unique to the file name"

tiffLst = [] # get a list of tiffs in the folder
    for root, dir, files in os.walk(rootDir)
        for filename in fnmatch.filder(files, search):
            tiffLst.append(os.path.join(root, filename))

if tiffLst:
    outTiff = os.path.join(outDir) + outName)

Here is where I would get stuck, not entirely sure which function to use in order to merge them together, but this will at least be a good start to walking the directory tree.