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<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">I have three geotiffs I created with QGIS 2.14.1. I need to merge them into one file.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">So I used gdal_merge:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">gdal_merge input1.tif input2.tif input3.tif –o output.tif<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">As a result I get a notification window that python has crashed and an output file.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">When I open the output.tif the resolution is only half as sharp as the input files.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">I know that gdal_merge uses the resolution of the first file so I tried gdal_merge in a different order of input files.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">The result is that I get the message that python has crashed on 2 of the 3 trials.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">The resolution of the outputfile remains the same.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">It seems I can adjust the resolution of the outputfile with the ps parameter:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">Gdal_merge –ps ? ? input1.tif input2.tif input3.tif –o output.tif<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">What numbers should I use to double the resolution?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">Meanwhile I used the ArcMap Mosaic to raster tool to create an outputfile from the tree input files.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">In ArcMap the resolution is OK and the tif displays fine. When I load the output.tif in QGIS only one color of the output.tif is displayed.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">Any help?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Tahoma","sans-serif"">Thanks,<o:p></o:p></span></p>
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