<div dir="ltr">Hello,<div><br></div><div>I am trying to georeference already georeferenced single band raster data using GDAL with four GCP's.</div><div><br></div><div>Input image is having Coordinate system GCS- WGS1984 (EPSG:4326).</div><div>Following Command is run on command Prompt:</div><div><br></div><div><div><i>"gdal_translate -of GTiff -gcp 72.4819 23.0179 72.4819 23.0179 -gcp 72.492 23.0079 72.492 23.0079 -gcp 72.4819 23.0086 72.4819 23.0086 -gcp 72.496 23.0169 72.496 23.0169 input.tiff output1.tiff</i></div><div><i>gdalwarp -r near -order 1 -co COMPRESS=NONE -s_srs EPSG:4326 -t_srs EPSG:4326 output1.tiff" output.tiff"</i></div></div><div><br></div><div><b>Issues</b>:</div><div>-> After running this command on command prompt and <span style="font-size:small;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">opening output generated file in QGIS</span>
the output is not having the coordinate system as EPSG:4326.</div><div><br></div><div>-> Image is opening somewhere <span style="font-size:small;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">else</span>
location in QGIS viewer. Hence the image is not properly georeferenced.</div><div><br></div><div>
<span style="font-size:small;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">-> For cross verification I ran georefrencing tool in QGIS with same input dataset it is giving the expected output and image is opening on exact Geographic location.</span></div><div><span style="font-size:small;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline"><br></span></div><div><span style="font-size:small;background-color:rgb(255,255,255);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">-> For cross verification, I copied generated gdal script from QGIS and ran again in Command Prompt and <span style="text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">opened</span>
output again in QGIS. The image is not as expected.</span></div><div><br></div><div><br></div><div><b>Questions</b>:</div><div>1. Is this above command is correct for georeferencing already georeferenced data?</div><div>2. Apart from above command Is there any another internal Command QGIS using for georeferencing image?</div><div>3. After running gdalwarp, why the output generated is not resampled and not having mentioned coordinate system.</div><div><br></div><div>Waiting For your valuable response.</div><div><br></div><div>-- <br><div class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><span style="font-size:12.8px">With Regards,</span><div><br><b style="font-size:12.8px">Sawan Nikam</b><b><br></b><b style="font-size:12.8px">Mob: +91-9753123988</b><b><br></b><div><div><div><div><b>Mail: <a href="mailto:sawan.nikam22@gmail.com" target="_blank">sawan.nikam22@gmail.com</a></b></div></div></div></div></div></div></div></div></div>
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