Hello, I'm having difficulties exporting a L2 Meris subset as geotiff.

Some images while opening them on Arcgis or Matlab do not perfectly overlap each other. It appears that a translation on x and y axis occurred.

Could you help me with this question?

Thanks for the help in advance best wishes Helder

Hello Marco, I don´t know how big is the displacement it is not the same for all the images... Some images work well but other don´t.

I'm processing the ocean colour of the cost of Portugal and some images have about 50 Km displacement on (dx,dy).

No I didn't reprojected the images, I did that to one image but it got a distortion. I'm going to try to reproject two bad images and then I'll give you some feed back.

I don't know how to add an image here but I would gladly send them to any image hosting site you wish just tell me which one.

Thanks !

Helder

Hi , I'm sorry for all the questions but I'm really hopping that you can help me.
As I said earlier the reprojection worked but now I can't work with these images on matlab because they are all twisted and with bad resolution I don´t know why.

If the exportation as geotiff worked and the images were perfectly overlapped that would be the best thing. Correcting what I said before the offset between images is no more than 5 kilometres (instead of 50km).

I will now wait for your reply and thank you in advance for all your help on this.

Best regards Helder

Probably this is because of the tie-points in the GeoTIFF. It is known that multiple GIS applications do not handle it very well, or can't handle it at all.
May be Matlab interpolates differently as BEAM does.
In general it is always a good idea to use projected images, when working with GeoTIFF.

best wishes
Marco

Good Morning everyone, Marco as you asked this is the WKT text.

GEOGCS["WGS84(DD)",
DATUM["WGS84",
SPHEROID["WGS84", 6378137.0, 298.257223563]],
PRIMEM["Greenwich", 0.0],
UNIT["degree", 0.017453292519943295],
AXIS["Geodetic longitude", EAST],
AXIS["Geodetic latitude", NORTH]]

As for the images they are bigger than 500pix with so I will make 2 smaller ones and post them next.


P.S : I use a bi-linear re-sampling process for the reprojection and although the image appears to lose resolution I think that they will do just fine for the work I am doing.


Best wishes Helder.

Hello Helder

I can't open the images you have attached. They seem to be broken.


best wishes
Marco