Hi,
I need to merge some Tiff4 (bw) raster and obtain 1 only more big tiff4
raster.
I'm try-ing this with gdal_merge.py
and using a comand like this:
python gdal_merge.py -o ../raster/216.tif -n 1 -ot Byte
../raster/10k/216*.tif
Unfortunately the resulted raster is intellegible (the input raster
Andrea,
I think the problem is that these are one bit files with
a black/white color table and by default gdal_merge.py
does not copy the color table. If you add the -pct
switch it should do so.
I imagine the result file does have pixels with values of
zero and one, but you won't see them as dif
Hi Frank,
thx for very rapid response.
gdal_merge.py now work and the result is intellegible.
testing the result ,
I notice the result is a 256 color image.
Instead the starting image was true CCITTFax4 raster.
This mean a huge dimension of files.
Is possible to have a real Tiff4 (1 bit color)
Andrea,
please read the gtiff driver page at http://www.gdal.org/frmt_gtiff.html
you need to add a few options, such as -co COMPRESS=CCITTFAX4 -co NBITS=1
Etienne
On Fri, Sep 2, 2011 at 7:15 PM, Andrea Peri wrote:
>
> Hi Frank,
> thx for very rapid response.
>
> gdal_merge.py now work and the
Etienne,
you are really reason.
I often forgot the great powerful of the tiff driver and so forgot also to
read the tiff driver page.
Thx to remenber me this.
Regards,
2011/9/3 Etienne Tourigny
> Andrea,
>
> please read the gtiff driver page at http://www.gdal.org/frmt_gtiff.html
>
> you need
Hi,
I'm try-ing to merge some tiff4 raster.
The call I'm using (thx Frank and Etienne) is these:
python gdal_merge.py -o ../raster/raster_1.tif -n 0 -ot Byte -pct
../raster/raster_1/*.tif
gdal_translate -co NBITS=1 -co COMPRESS=CCITTFAX4 -co TFW=YES
../raster/raster_1.tif ../raster/raster_2.ti
Le lundi 05 septembre 2011 09:55:52, aperi2007 a écrit :
> Hi,
> I'm try-ing to merge some tiff4 raster.
>
> The call I'm using (thx Frank and Etienne) is these:
>
> python gdal_merge.py -o ../raster/raster_1.tif -n 0 -ot Byte -pct
> ../raster/raster_1/*.tif
> gdal_translate -co NBITS=1 -co COMPR
> Are you sure you are using a 64bit GDAL ? AFAIR, OSGeo4W is 32bit only.
>
Thx for response.
I download the gdal 64bit version.
explode it on a single folder.
I use osgeo shell only as environment for python and go in the folder
gdal64 to call its gdal_merge.py.
I guess the libraries used was
On 09/05/11 20:08, aperi2007 wrote:
But gdalwarp is a tool I never will think to use for this.
Is gdalwarp capable to merge raster ?
According to previous messages posted on this list, gdalwarp is THE tool
you must use to merge rasters. gdal_merge.py is only a demo script that
has been writ
