Merge tif files with python

Question

I'm also having problems with running gdal_merge.py within another python script and I cannot run it. I already checked a similar problem here. My example is as follows:

First I set my workspace and locations:

sys.path.append('C:/Python27/ArcGIS10.2/Scripts/') 
import gdal_merge as gm workspace="D:/Satellitendaten/rapideye/img/testregion/cannyedge/out/"
os.chdir(workspace)

Then I run:

sys.argv = ['o', 'out.tif', 'allre1.tif', 'allre10.tif', 'allre11.tif', 'allre12.tif', 'allre13.tif', 'allre14.tif', 'allre15.tif', 'allre16.tif', 'allre17.tif', 'allre18.tif', 'allre2.tif', 'allre3.tif', 'allre4.tif', 'allre5.tif', 'allre6.tif', 'allre7.tif', 'allre8.tif', 'allre9.tif']

I get:

0...10...20...30...40...50...60...70...80...90...100 - done.

But also ERROR 4:

`out.tif' does not exist in the file system, and is not recognised as a supported dataset name.

So the output is not created. Maybe someone can help me out with the issue to merge different tif files to a single tif?

• asdflkjwqerqwr: Is there a typo at 'gm workspace'? Why is it two words?
• crmackey: Just a thought, setting sys.argv as you are may be causing a problem. sys.argv[0] is always the path of the current script running. Whenever I pass in args in this way I usually do sys.argv[1:] = [#your args here]. I should add that when I do that, it is when using ArcGIS/arcpy so it may not apply for gdal.

Answer 1

As crmackey notes in his comment, the first element in sys.argv needs to be the current script. You also need to use '-o' instead of 'o' as your first argument for gdal_merge

Try:

sys.path.append('C:/Python27/ArcGIS10.2/Scripts/') 
import gdal_merge as gm 
workspace="D:/Satellitendaten/rapideye/img/testregion/cannyedge/out/"
os.chdir(workspace)
sys.argv[1:] = ['-o', 'out.tif', 'allre1.tif', etc...]