On 10/26/07, Moritz Lennert <[EMAIL PROTECTED]> wrote: > Hello, > > This question is a bit off-topic, but related to what we need to do with > GRASS: > > We have a series of georeferenced .tif files accompanied by .tab files > which look like this: > > Definition Table > File "s5_15 nw3_b-iii.tif" > Type "RASTER" > (513881,9523020) (1008,1098) Label "Pt 1", > (519881,9523020) (10493,1111) Label "Pt 2", > (519881,9517020) (10451,10523) Label "Pt 3", > (513881,9517020) (990,10509) Label "Pt 4" > CoordSys Earth Projection 8, 104, "m", 15, 0, 0.9996, 500000, 10000000 > Units "m" > > > However, gdal does not support the Mapinfo's CoordSys: > "only control points used, Coordsys ignored" > (http://www.gdal.org/frmt_gtiff.html). > > I guess that if we could transform these files into ESRI world files > (http://www.gdal.org/frmt_various.html#WLD), we could import them easily > with GDAL. But how to do this, as ESRI world files give transformation > parameters, not points and projection info ? > > Or is this the wrong approach ? > > We can obviously easily import each file into an XY location and then > run i.rectify on the basis of the available points, but I was wondering > whether there is a better way. > > Moritz
If you have access to MapInfo and/or ArcView, there are some scripts floating around that will convert TAB registered images to TFW registered. One that I found was: http://spatialnews.geocomm.com/community/lists/viewmessage.phtml?id=35852 If not, you could write a script that would generate a TFW from the TAB. The TFW requires that the coordinates of the upper left pixel be specified, and the size of each pixel be specified. The TAB is a little different as is specifies three or more pixel/coordinate pairs, but you could work backwards for the pixel/coordinate pairs to calculate the upper left pixel and pixel size. The TAB also specifies the coordinate system, which would have to be converted into a separate .PRJ file. Regards, -- Richard Greenwood [EMAIL PROTECTED] www.greenwoodmap.com _______________________________________________ grassuser mailing list grassuser@grass.itc.it http://grass.itc.it/mailman/listinfo/grassuser