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I'm trying to programmatically export a symbolized raster to an RGB TIF using ArcGIS, i.e.: perform the equivalent of Export Raster Data in ArcMap with Use Renderer and Force RGB activated.

I followed the beginning of Use python to disable "Scale map elements proportionally to changes in page size" to access ArcObjects in Python.

I'm trying to re-create the code in this discussion to eventually create a RasterLayerExport object. Before that, though, I find myself incapable of creating a WorkspaceFactory.

I tried running:

import arcpy

from snippets102 import *
from comtypes.client import GetModule, CreateObject

import comtypes.gen.esriFramework as esriFramework
import comtypes.gen.esriArcMapUI as esriArcMapUI
import comtypes.gen.esriCarto as esriCarto
import comtypes.gen.esriDisplay as esriDisplay
import comtypes.gen.esriGeoDatabase as esriGeoDatabase

wkspf = CreateObject(esriGeoDatabase.WorkspaceFactory, interface = esriGeoDatabase.IWorkspaceFactory)

But this gives me the following error:

Traceback (most recent call last):
  File "C:/Users/AndyPL/.PyCharmCE2017.2/config/scratches/scratch_1.py", line 14, in <module>
    wkspf = CreateObject(esriGeoDatabase.WorkspaceFactory, interface=esriGeoDatabase.IWorkspaceFactory)
  File "C:\Python27\ArcGIS10.4\lib\site-packages\comtypes\client\__init__.py", line 238, in CreateObject
    obj = comtypes.CoCreateInstance(clsid, clsctx=clsctx, interface=interface)
  File "C:\Python27\ArcGIS10.4\lib\site-packages\comtypes\__init__.py", line 1225, in CoCreateInstance
    _ole32.CoCreateInstance(byref(clsid), punkouter, clsctx, byref(iid), byref(p))
  File "_ctypes/callproc.c", line 945, in GetResult
WindowsError: [Error -2147221164] Class not registered

Odd, since creating a PlugInWorkspaceFactory works fine. Does anyone else get this error?

|improve this question
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    This is one of the odd ones, you create an IWorkspaceFactory from the workspace type: AccessWorkspaceFactory for personal GDB, FileGDBWorkspaceFactory for file GDB etc.. see the coclasses at resources.arcgis.com/en/help/arcobjects-net/componenthelp/… and look at the example resources.arcgis.com/en/help/arcobjects-net/componenthelp/… for ShapefileWorkspaceFactory (ctrl + F to find it). Clearly on line 11 of the example the workspacefactory is being created as RasterWorkspaceFactory. – Michael Stimson Oct 12 '17 at 0:32
  • Thanks (again) for your answer Michael. So would it be something like wkspf = CreateObject(esriGeoDatabase.RasterWorkspaceFactory, interface = esriGeoDatabase.IWorkspaceFactory)? – Andrew Plowright Oct 12 '17 at 1:43
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    The RasterWorkspaceFactory is in DataSourcesRaster, see resources.arcgis.com/en/help/arcobjects-net/componenthelp/… I'm not sure what the arcpy import is for that, presumably import comtypes.gen.esriDataSourcesRaster as esriDataSourcesRaster. Were I certain of this I would have posted an answer; When you sort this out can you post your working code as an answer to your own question, I too would be interested to see it. – Michael Stimson Oct 12 '17 at 2:18
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Thanks to Michael Stimson for figuring this one out.

In this specific example, what I needed was a RasterWorkspaceFactory, and not a WorkspaceFactory. 

from snippets102 import *
from comtypes.client import GetModule, CreateObject

import comtypes.gen.esriGeoDatabase as esriGeoDatabase
import comtypes.gen.esriDataSourcesRaster as esriDataSourcesRaster

wkDir = "C:/YourWorkspace/"

wkspf = CreateObject(esriDataSourcesRaster.RasterWorkspaceFactory, interface=esriGeoDatabase.IWorkspaceFactory)
wksp = wkspf.OpenFromFile(wkDir, 0)

I'm afraid I still don't know how to access WorkspaceFactory, though.

|improve this answer
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    There is no WorkspaceFactory (generic), this is a very odd object in that the IWorkspaceFactory interface is initialized with a CoClass only. Normaly an interface is initialized with the same class, IPoint for example is initialized to PointClass() in C# esriGeometry.Point in python. Another example of this odd instantiation is IPointCollection, there is no PointCollection class, the interface is initialized as one of the CoClasses (Ring, Path, Multipoint etc..). – Michael Stimson Oct 12 '17 at 21:01

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