Re: [Qgis-user] one raster from tiles
Le Monday 21 April 2008 14:04:39 Lionel Roubeyrie, vous avez écrit : Hi all, I have several tiles rasters (geotiff) describing a large area in high resolution, and generally I work on a small area, having to import all tiles because they don't have explicit names (and without the possibility to put them directly under a group (see a previous post), which should be a great improvement). Then, is it possible to extract/create a new raster for the desired area with QGIS/GRASS (know it's possible with Arcmap, with difficulties) ? Thanks Hi Lionel, You can use gdaltindex to create an indexof your tile in shapefile format, after displaying it you can show the location field on your map and find the filename of the Raster you have to load for your area. If you want to extract an area from your raster you can again use gdal [1] with some option to cut all data out of your area. I think you can use g.region to zoom into your area and then export the raster from your view region, after creating one main raster. I am agreeing with you for a better group management ;) May I need to create a new ticket? Another possibility should be that QGIS manage index file. Y. -- Yves Jacolin --- http://softlibre.gloobe.org ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] one raster from tiles
Big thanks Yves for pointing gdal (never thinking at all for it), there's a special command to merge multiple tiles into one with gdal_merge.py. Keep gdaltindex under the pillow :-) Le lundi 21 avril 2008, Jacolin Yves a écrit : Le Monday 21 April 2008 14:04:39 Lionel Roubeyrie, vous avez écrit : Hi all, I have several tiles rasters (geotiff) describing a large area in high resolution, and generally I work on a small area, having to import all tiles because they don't have explicit names (and without the possibility to put them directly under a group (see a previous post), which should be a great improvement). Then, is it possible to extract/create a new raster for the desired area with QGIS/GRASS (know it's possible with Arcmap, with difficulties) ? Thanks Hi Lionel, You can use gdaltindex to create an indexof your tile in shapefile format, after displaying it you can show the location field on your map and find the filename of the Raster you have to load for your area. If you want to extract an area from your raster you can again use gdal [1] with some option to cut all data out of your area. I think you can use g.region to zoom into your area and then export the raster from your view region, after creating one main raster. I am agreeing with you for a better group management ;) May I need to create a new ticket? Another possibility should be that QGIS manage index file. Y. -- Lionel Roubeyrie - [EMAIL PROTECTED] Chargé d'études et de maintenance LIMAIR - la Surveillance de l'Air en Limousin http://www.limair.asso.fr ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] one raster from tiles
I think that you have brought up an interesting idea though. After getting used to the idea of being able to use a tile index for large raster data sets in MapServer. I have really wished that this feature existed in desktop GIS. In ArcGIS, you can create a raster catalog, but you have to use a geodatabase and their 'tile index' layer doesn't give actual footprints of the images, just the bounding boxes. I think that it would be great to be able to use a tileindex in qGIS. David. On Mon, Apr 21, 2008 at 8:51 AM, Lionel Roubeyrie [EMAIL PROTECTED] wrote: Big thanks Yves for pointing gdal (never thinking at all for it), there's a special command to merge multiple tiles into one with gdal_merge.py. Keep gdaltindex under the pillow :-) Le lundi 21 avril 2008, Jacolin Yves a écrit : Le Monday 21 April 2008 14:04:39 Lionel Roubeyrie, vous avez écrit : Hi all, I have several tiles rasters (geotiff) describing a large area in high resolution, and generally I work on a small area, having to import all tiles because they don't have explicit names (and without the possibility to put them directly under a group (see a previous post), which should be a great improvement). Then, is it possible to extract/create a new raster for the desired area with QGIS/GRASS (know it's possible with Arcmap, with difficulties) ? Thanks Hi Lionel, You can use gdaltindex to create an indexof your tile in shapefile format, after displaying it you can show the location field on your map and find the filename of the Raster you have to load for your area. If you want to extract an area from your raster you can again use gdal [1] with some option to cut all data out of your area. I think you can use g.region to zoom into your area and then export the raster from your view region, after creating one main raster. I am agreeing with you for a better group management ;) May I need to create a new ticket? Another possibility should be that QGIS manage index file. Y. -- Lionel Roubeyrie - [EMAIL PROTECTED] Chargé d'études et de maintenance LIMAIR - la Surveillance de l'Air en Limousin http://www.limair.asso.fr ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
