Merge Raster Layers in QGIS (Create a Raster Mosaic)
Ғылым және технология
This QGIS tutorial demonstrates how to merge raster layers to create a raster mosaic in QGIS using GDAL tools. QGIS makes it easy to merge multiple raster layers into a single file.
Step-by-step instructions: opensourceoptions.com/blog/me...
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Пікірлер: 43
Not all heroes wear capes! Well you might wear a cape for all I know, but seriously: THANK YOU SO MUCH! I was starting to panic. I have one week to make a 3D map for a TV show. Have done it before, but not at this scale. I didnt have three tiles, but 658 tiles in a horrible mosaic of different gray scales. Now I have one big beatiful and smooth terrain. Thank you again sir!!
@geospatialschool
Жыл бұрын
Glad I could help!
Thank you. This video really saved me from so much headache.
@geospatialschool
2 жыл бұрын
Glad it helped!
Thanks for your video! I am working with images from Sentinel 2. Do you know the procedure if the images have some black areas and if they have some overlapping areas, how can I choose the image I want in the final product? From already thank you very much
Thank you :)
Very helpful, glad I found it, thanks!
@geospatialschool
6 ай бұрын
Glad it was helpful!
Thanks. I resolved in another way due to I got an error during process. Every tile has a min and max elevation according to white (max) and black (min); so every tile has more or less its own grayscale. I downloaded 18 tiles with HUGE tone differences between each other: a mess. What I did is to find the lower altitude and rewrite this min to all tiles (in the video is 1389.49); same with max (in the video 3301.7). Dobleclicking the layer will open a info chart to change these data. Tara! The result its a beautifull smooth heightmap.
Thanks for useful method and your deep knowledges in qgis.
@geospatialschool
Жыл бұрын
It's my pleasure
Thank you for this
@geospatialschool
2 жыл бұрын
You're welcome
Can you merge aerial images with the raster to give it colour then export as a colour point cloud
Thank you very much
@geospatialschool
2 жыл бұрын
You are welcome
Thanks for sharing
@geospatialschool
3 жыл бұрын
Thanks for watching!
Excuseme, is it possible to change the merging order? I'm merging different bands of image to a single image with multiple bands,but it seems QGIS has its own default merge order.
when i try to merge 2 rasters a black screen appear in there place after the proccess any help?
Thank you for this! I have a question though, I've tried it with a large amount of files (70Gb of information) and it tells me there isn't enough disk space to store the resulting file. The disk however has over 400Gb of free space. Does the merged file actually take that much more space than the mosaic files?
@geospatialschool
3 жыл бұрын
It could be that the error is not for writing the result to disk, but loading it into memory. Depending on how it works behind the scenes you could be limited by RAM
@hohvideos3238
2 жыл бұрын
it also may be a compression issue. If the original files are compressed and the resulting file has no compression, it can be a lot larger than 70 gb.
Hello, thanks for the video. I have a question please, why I don't have python3 -m in the GDAL/OGR console call, thank you
What're your machine configuration? I'm trying to merge some files in a i5 with 8gb ram and a SSD The files size are 600 mb And does it works with overlayed layers?
So usefull. Just a question... when i do the same with two different dem, the merged output has a maximum value lower than the maximum in one of the original ones. Some idea about why is it doing this? If i check the higher areas with the "identify features" of the merged file I find pixels with higher values than the maximum... it's just weird
@geospatialschool
2 жыл бұрын
It's probably just that the statistics weren't recalculated or were only calculated on a sample of values. There's a QGIS tool to calculate the statistics
@ViCtOrBization
2 жыл бұрын
@@geospatialschool Your're right, thanks a lot
@danielwarren4541
2 жыл бұрын
@@geospatialschool can you direct me to the tool you mention - I am having the same problem
very cool!! How could I merge a raster of the whole country? I feel that it is not feasible, because the memory goes to infinity. But is there a way around it?
@geospatialschool
10 ай бұрын
Depends on the resolution of your rasters and the amount of memory your machine has. It could be done, it might take forever and require writing custom code. Or a machine with enough memory
Hi. Can you please let me know why do the min and the max elevations of the merged raster dont tie in with the other individual rasters? Second, can you please point me to your video wherein you can stamp rasters with some intersection between them and asks user the sequence to stamp?
@geospatialschool
2 жыл бұрын
You may just need to recalculate the statistics. Sometimes the raster statistics are computed from a sample instead of all values.
@pitruchhaya
2 жыл бұрын
@@geospatialschool Thanks for your response. I will check this. Can you please answer my second question too?
@gaborfekets6899
2 жыл бұрын
@@geospatialschool Hi, thanks for your video. I have the same problem. After clip, or merge the new MIN/MAX values are different. The new MAX value is higher, then the old image file. Recalculated, but still the same problem. I'm new at this QGIS world, can you please help how to step forward? Thanks.
@geospatialschool
2 жыл бұрын
Are the statistics on the original rasters correct? And how different are the new values? Resampling does happen when doing the merge so the values may be slightly different.
it gave an error saying it was saving in too many bands what is a band?
hi, I have a county size group pf 1000 lidars (.laz's)that I had to break up into 3 projects because QGIS kept choking on any group larger than around 500 layers. How would I go about merging all 3 of those groups of layers into one project/tiff file. Thx in advance for any help. ....Dan
@geospatialschool
8 ай бұрын
With that many files I wouldn't use QGIS. You're getting to a point where you probably want to store and analyze those data on the cloud
@dak4482
8 ай бұрын
ok thx @@geospatialschool
Qgis 3.18 please...
@geospatialschool
3 жыл бұрын
It's the same.
why are u so confused with whatever ur trying to show in thi video....