If the problem is from the number of files (and not actually it's size) then creating a virtual raster may help to solve it.
https://docs.qgis.org/3.4/en/docs/user_manual/processing_algs/gdal/rastermiscellaneous.html#build-virtual-raster Alexandre Neto QGIS Support www.qcooperative.net A segunda, 18/11/2019, 19:36, Nicolas Cadieux <[email protected]> escreveu: > Hi, > > I ran into same problems when dealing with a few thousand files. The idea > was to load the very small shp files created by another process and then > merge then. I solved the problem by loading and merge it then I SAGA. It > generally loads everything into memory and probably does not keep a file > handle once the file are open. I believe this issue is created by Windows > and not QGIS. I remember being told to go on Linux as this maximum > operating system file max can be modified with a script. > > Nicolas > > > Le 18 nov. 2019 à 04:59, Jésahel Benoist <[email protected]> a écrit : > > > > From my experience, GeoTIFF has a long history and is a more > > appropriate format to handle multiple large rasters. As a container, > > it could handle misc compression format (JPEG an other), misc > > representation at different scales (resolution is not a problem), misc > > color modes with raster/vectorial alpha layer, and so on. In one of my > > projects I handle more than 400 raster files (4000x4000x32) without > > any problem. > > Of course, a better and final choice would be to tile everything, but > > it is sometimes difficult with older maps. > > > >> Le lun. 18 nov. 2019 à 10:12, Patrick Dunford > >> <[email protected]> a écrit : > >> > >> Good day to all > >> > >> One of the user experiences I have had from using the Qgis software has > been with projects using large numbers of raster tile layers. These layers > are generally tiles that have a size of 4800x7200 pixels in GeoJPEG format > and have either been downloaded directly from tile servers to these locally > stored files, or created from downloaded tiles with other layers overlaid > in Gimp projects. > >> > >> There appears to be some architectural limit in Qgis desktop software > relating to either the total number of raster layer [files] in a project or > to the total number of pixels in raster layer [files] in a project. This is > unrelated to the number of layers or pixels currently enabled for display > in the map canvas. In practice, the appearance of this limit is that it is > kicking in long before the host computer's own physical resources are > anywhere near fully engaged. Map digitising and editing is done on systems > with 32 GB of physical memory (RAM) and 200 GB of SSD-based virtual memory > (swap) and these systems are able to edit very large Gimp projects for user > tile creation that often engage all of the system's physical memory and > around 100 GB of the virtual memory without problems. But these types of > numbers are in practice never seen with Qgis projects when the raster layer > limit is being seen. > >> > >> The appearance of a raster layer limit is generally experienced in > older versions of the software by layers being displayed on the canvas as > garbage, and in newer versions by the software crashing. It will only start > working again if raster layers are removed from the project. However, when > layers are loaded from WMTS servers, no appe > _______________________________________________ > Qgis-user mailing list > [email protected] > List info: https://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
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