Georeference raster in WGS84 and project in North azimuthal in QGIS

Question

I have a raster (JEPG) image from a full planet surface (in this case Jupiter).

I use QGIS and its plugin Georeferencer to add control points on the image. I use the four corners. Then I use Gdal to warp the new georeferenced image into north azimuthal projection. But the final image isn't a circle at all! So I probably missed something during the process.

Here is the full process I followed:

1. Open the raster in Georeferencer QGIS's plugin
2. Set the coordinate reference system as WGS84 (EPSG:4326)
3. Select four points (corners) of the raster and set the destination value:
   1. Select upper left corner and set X/Y to -180/90
   2. Select upper right corner and set X/Y to 180/90
   3. Select lower left corner and set X/Y to -180/-90
   4. Select upper right corner and set X/Y to -180/-90
4. Configure the transformation setting to the following parameters:
   • Transformation Type: Polynomial 1
   • Resampling method: cubic
   • Compression: None
5. Georeference image.
6. Warp into azimuthal projectino with gdarwarp : gdalwarp -t_srs "+proj=aeqd +lat_0=90 +lon_0=0 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs" jupiter_georef.tif jupiter_circle.tiff

Unfortunately, the final image doesn't match a full circle.

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The georeferencer screen :

Output:

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I also tried to use QGIS to warp the georeferenced image by changing the coordinate system. The output is better but the circle is cropped by a square and it has a thin line missing.

Any clue to solve this problem?

Answer 1

Finally I managed to make a simple polar projection without georeferencing the raster image. For that I used ImageMagick with the following command line:

convert raster_input.jpg -virtual-pixel HorizontalTile -background Black -distort Polar 0 -fuzz 50% -trim polar_output.jpg

I know there is another solution with Gimp through the Filters > Distort > Polar Coordinates tool. But I chose the ImageMagick approach as I have several image to treat and its easiest to script it.