If someone has the time, could they go through this rough draft workflow to see if they can follow it for the creation of a geotiff with TFW? It may be rough.
I saw Mr. Cow's thread on the old topo maps. If you georeference those, you can overlay them in Google Earth or CAD or other. I am planning to georeference an 1858 County Map that we just had photographed.
I don't mind taking a look but I cannot open your link - comapny security and firewalls block access. If you don't have other takers, shoot me an email.
Bah google drive and your advanced button... Try it now or
Geotiffs are composed of two files: the TIF and the TFW.
TIF: Image, we have all seen them.
TFW: Tiff World File, tells the computer where to put the TIF.
COMBINING AND CLIPPING
Import the existing geotiff(s) into QGIS.
RASTER -> EXTRACTION -> CLIPPER
Input file (raster) The TIF
Output file FILENAME: _______________________
No data value OFF
Clipping mode
Click in one of the XY boxes
Drage over the area to export
Load into canvas when finished ON
OK
Popup windows:
OK
OK
CLOSE
GEOREFERENCE
Back in CAD
Grab some references. Road line stripes, Buildings, Rooflines, Chimneys, Utility Poles, ETC.
Save as DXF
FILENAME: _______________________
Back in QGIS
Import the DXF
Import the TIF if it is georeferenced
RASTER -> Georeferencer -> Georeferencer
Add the TIF
Settings -> Transformation Settings
Tranformation Type Linear
Resampling Method Nearest neighbour
Compression None
Create World File NO
Output raster FILENAME: ________________
Target SRS MA Mainland or otherwise
Generate PDF Map Have not tried it yet
Generate pdf report Have not tried it yet
Set target resolution Disabled
Use 0 for transparency when needed Off
Load in QGIS when done On
Click on a point in the Georeferncer
From map canvas
Click on the similar point in the QGIS window.
OK
Or you can manually add coordinates.
Do the next... and next and next until you have as many as you need.
Start georeferencing (The green go triangle)
If your settings are not set, they will be now.
It comes into QGIS
Settings -> Transformation Settings
Tranformation Type Linear
Resampling Method Nearest neighbour
Compression None
Create World File YES
Output raster Disabled
Target SRS MA Mainland or otherwise
Generate PDF Map Have not tried it yet
Generate pdf report Have not tried it yet
Set target resolution Disabled
Use 0 for transparency when needed Off
Load in QGIS when done On
Explorer
Rename the WLD file to the same name as the output TIF
Copy and name the WLD to TWF
Actually GeoTIFF files contain their own georeferencing information in their file headers. A .tfw file is ignored by a GeoTIFF file altogether. If you want to *re-write* out a GeoTIFF file with data from a tfw file, here's a link to the GDAL processing library function that can do that sort of thing for you:
http://www.remotesensing.org/geotiff/faq.html
Rudy Stricklan, RLS, GISP
Good point but Autodesk Map and Carlson Point Cloud have not responded well to the file output from QGIS without the TFW file. The TIF has gone right back into QGIS without the WLD or TFW supplemental files. I run the process twice because I cannot make georeferencer dump both the world file and the tif image.
Maybe this link from Autodesk has some relevance?
http://forums.autodesk.com/t5/autocad-map-3d-general/world-files-not-recognised/td-p/3504088/page/2
Rudy Stricklan, RLS, GISP
Meh, my main drive here is colorizing point clouds in Carlson with aerial photography (in Beta, will be available in the 2016 release). When the aerial is off by a bit, the point cloud is colored like a 4-year old's coloring book. I need to adjust the tif and Carlson apparently needs the TFW file to do it's thing.
I really wanted fresh eyes to look at my procedure so I could share this with the surveyors here (and so they could follow it). There are benefits to georeferencing images with the embedded or adjacent world data. I'll revise the header to reflect the semantics, but again Meh.
