Hi All,
Is it possible to change the projection of Raster layer. I'm using GdalRasterLayer for image. it is original format is Arc/Info ASCII Grid. If the GdalRasterLayer cannot change the projection is there any other layer type which I could use to change the projection.
My raster image projection is EPSG:28350. My requirement is to overlay this image with Google map layer on openlayers.
Thanks and Regards
Amila
Hi Amila,
We don’t have a GdalRasterLayer for now.
Do you means GdiPlusRasterLayer or GeoTiffRasterLayer or some other RasterLayer?
In fact, our raster layer support reprojection, as below is a quickly sample:
ManagedProj4Projection proj4 = new ManagedProj4Projection();
proj4.InternalProjectionParametersString = ManagedProj4Projection.GetEpsgParametersString(28350);
proj4.ExternalProjectionParametersString = ManagedProj4Projection.GetGoogleMapParametersString();
proj4.Open();
GdiPlusRasterLayer rasterLayer = new GdiPlusRasterLayer();
rasterLayer.ImageSource.Projection = proj4;
Regards,
Don
Hi All,
I mean GdalRasterLayer which comes with FDO extention. Can I use GdiPlusRasterLayer or GeoTiffRasterLayer for Arc/Info ASCII Grid? My file extension is .asc.
In GdalRasterLayer ImageSource.Projection is read only. Therefore it cannot set projection. I believe raster layer should come from FDO extension to support this kind of file.
Are there any other FDO extension or other raster layer type which support Arc/Info ASCII Grid (*.asc) format and also ImageSource.Projection is not read only
Thanks
Amila
Hi Don,
In my version of Thinkgeo dlls I could not access GdiPlusRasterLayer ImageSource.Projection property. I use wms server version 6 dlls. Even In rastersource documentation under public properties Projection is with *. I’m not sure what that is mean. (wiki.thinkgeo.com/wiki/ThinkGeo.MapSuite.Core.RasterSource#.2AProjection)
Therefore could you confirm that GdiPlusRasterLayer ImageSource.Projection is accessible? If so please let me know to how to set it. If it can set projection at least I could ask client to provide images on tif format.
Regards
Amila
Hi Amila,
I guess you are using the “Production Version”, which is based on the 6.0 public release version and just includes the bug fixed. Can you switch to “Development Version”, which includes the bug fixed and new features added since 6.0 release.
Additionally, I think you still need to use GdalRasterLayer, GdiPlusRasterLayer is for windows native images while GeoTiffRasterLayer is used for .tiff images.
Thanks,
Johnny
Hi Johnny,
Thanks for the reply. With development version I can set Projection property.
My current issue is I would like to apply style into raster layer using values of attribute in the tif file. I have work with feature layers before those are easier to set styling by set defaultareastyle or by adding into customstyles.
Do you have idea on how to do it with any type of raster layer and how to specify which attribute to use for styling as we set columname on feature styles.
My images are in tif format. With GdiPlusRasterLayer it shows on map without styling. But GeoTiffRasterLayer doesn't show up my image. Could you also explain the use of LowerThreshold, UpperThreshold and KeyColors properties?
I have attched a sample file for your reference.
Regards
Amila
file.zip (63.8 KB)
Hi Amila,
It is not able to change a tif’s style, because tiff essentially is a picture and how it looks like is decided by the picture.
I tried to show your tif file by using both GdiPlusRasterLayer and GeoTiffRasterLayer, but both failed because the file.tfw file is not provided, would you please provide it to us?
If you just want to show a tif file from scale A to scale B, then you can set “GeoTiffRasterLayer.UpperThreshold = B;” and “GeoTiffRasterLayer.LowerThreshold = A;”
If you tif image contains a color A, and you want to make color A transparent in the mapcontrol, then you can use GeoTiffRasterLayer.KeyColors.Add(A);
Hope it helps.
Edgar
Hi Edgar,
Noted. Thanks for the info.
Regards
Amila
You are so welcome.
Johnny
What is the state of this bug fix? Can we get it in a production release yet? We are also experiencing this same problem but I hesitate to move to the development version.
Mike
Hi Michael,
Yes, it have been fixed in the latest production version (7.0.0.223 or later). please download it and have a try.
If the issue persists, Don’t hesitate to let us know.
Regards,
Troy
Thank you Troy. We have tried the latest version and it does seem to solve the projection issue. Thanks!
Thank you Troy. We have tried the latest version and it does seem to solve the projection issue. Thanks!
Hi Michael,
You are so welcome.
If any other queries, don’t hesitate to let us know.
Regards,
Troy