Gaofen-1 image pansharpening

OTB Usage
1

Hi,
I orthorectified both MUX and PAN products from Gaofen 1 satellite using OTB. I then tried the pansharpening using otbcli_BundleToPerfectSensor, but there is a little misalignment between those two products, and hence the result is unusable. Please see below the snapshot:

result
result831×602 802 KB

Any idea how can I fix this misalignment?

Thanks.
Pritimoy

2

If the misalignement is small, you can try to use the FineRegistration application to register one image into the other.

You can also try to perform the registration before the orthorectification, by refining the sensor model of one of the two images. See https://www.orfeo-toolbox.org/CookBook/recipes/residual_registration.html.

3

Many thanks for your reply.
The misalignment is very small and hence I tried the FineRegistration. However, I am now stuck with the following error:

Blockquote
2020-02-24 14:19:48 (FATAL) FineRegistration: itk::ERROR: FineRegistrationImageFilter(000001BB45BD98C0): Inputs do not occupy the same physical space!

4

Hello,

Indeed, the two input of FineRegistration should occupy the same physical space (same size, origin …), so you can’t use it directly on the MUX and PAN products before using BundleToPerfectSensor

BundleToPerfectSensor is actually the combination of two applications :

So what you can do to perform the registration is to chain these 3 applications :

  1. SuperImpose
  2. FineRegistration (now the two inputs are in the same physical space)
  3. Pansharpening

Note that in FineRegistration, the output you want to use is the one given by the -wo parameter. -out is the computed disparity grid.

Tell me if it works.

Cédric