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Topic: GF satellites

I am a PHD in Beijing Normal University, Now I want to use Cosicorr for glacier moving detection, and have two questions about the implementation details. Your advice and explanation will be much appreciated!

1、I learned that several satellite imagery specific can be used in Cosicorr according to the User’s Guide, including the ASTER, Formosat-2, SPOT/SPOT5, SPOT6-7, Pleiades, Quickbird and the Worldview. Now, the data that I want to use for moving detecting are the images from Chinese satellite GF-1, with the spatial resolutions 16m, 8m, and 2m. The GF series satellites now are widely used in China, so, I wonder how can I use GF images for glacier moving detection by Cosicorr.

2、If I want to use GF images by Cosicorr, do I need to preprocess the GF images to achieve the Cosicorr data standard or I have to re-write the code?

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Re: GF satellites

Hello,

indeed, GF satellites are not (yet?) supported by COSI-Corr. That means that you need to orthorectify and coregister the images with another software that support GF sat. Once the images are orthorectified and processed, you can use COSI-Corr to compute the glacier displacement map; at that point it does not matter anymore that the images are from non-supported sat.

If we were to implement GF sat into COSI-Corr we would need the description and ancillary data of the raw imagery. I haven't looked into it and don't know if that information is publicly available.

Best,
Francois

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Re: GF satellites

Hi Francois,

Thank you for your reply. You mean that I can use COSI-Corr for computing the glacier displacement map after the GF satellite images were orthorectified and coregistered? I hope to talk about the details about the implementation with you after the data processing is done.

You said that the GF images must be coregistered before used in COSI-Corr, I wonder if there is standard (suggested standard images like spot、worldview、aster)? Or I just have to make sure the GF images have the same reference image or control points?

I am sorry that it is my first time to use COSI-Corr, my question maybe too simple.

Best wishes!

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Re: GF satellites

Hello,

yes, you can use COSI-Corr for computing the glacier displacement map after the GF satellite images are orthorectified and coregistered.
The two images don't need to be registered to a standard reference, it's relative to each other that they need to be coregistered. To achieve good coregistration, you need to make sure that the images are correctly georeferenced to the DEM when orthorectifying them; this will insure proper topographic parallax correction.

Best,
Francois