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I want to create a mosaic of satellite imagery in .tiff format. I want to create an actual mosaic, not a vrt, because afterwards I will cut the image in to tiles that make sense for my users. Gdal merge is not an option because of the size of my images (I have tried many times and get a memory error).

The problem I have is that the the result is a gap in the data while the original files overlap nicely (see images). When running I set my nodata value correctly ("0" in this case).

the two images displayed in QGIS with transparency set for "0"

result of running gdalwarp

The images are 16 bit, and the collection period spans 2 years so there are huge color differences. I am running QGIS 2.6 and Gdaltools 1.2.29 on W7 64 bit with 8GB Ram

I run the following command: gdalwarp -dstnodata 0 -of GTiff A.TIF B.TIF TEST_warp

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  • Whats wrong with Gdal VRTs? Whats why it was created. Also if would be good idea if you'd posts some more info about your images. For example the output the gdalinfo for your images you want to merge.
    – nickves
    Nov 20, 2014 at 13:50
  • It was typo only in our question with "o" as you wrote, wasn't it? I mean letter "ou" vs. number "zero". Your images does not look any special but as requested, send gdalinfo reports and exact commands you have used and if possible, images which show the seam for downloading. You can clip out most of the image data, the seam is what is interesting.
    – user30184
    Nov 20, 2014 at 14:41
  • Yes, thank you. I meant zero. I will post the requested info asap as I don't have access to the images right now. The reason I want a .tiff and not a VRT is because the VRT on another part of my AOI messed up the colors. And my ultimate goal is to have rasters that are useable in Mapinfo since that is the main GIS of the users. If you have a page with more info about VRT, I would love to read it. It is my first time processing imagery so everything I say i concluded be reading online.
    – Gin
    Nov 21, 2014 at 12:54
  • Could you copy the command line here? Then we'd know what you exactly tried.
    – markusN
    Nov 21, 2014 at 13:30

1 Answer 1

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After searching around for similar situations, I fixed the issue by'

  1. Reordering the bands to RGBN (They were BGRN) with gdal translate
  2. Converting the images from Uint16 to Byte with gdal_translate
  3. Lastly, I warped them using gdalwarp using the -tr and -tap options.

The solution at step 3 I found at: Holes between imagery tiles projected using gdalwarp

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