Remove seam from two merged images

Hi

I see several issues to address.

In your image - which is putting a mirror image together, you have :

Two perspectives (i.e. two vanishing points) this shows on the floor and especially on the roof bars.

A centre floor area with diagonals that crash

A centre area that needs cleaning up as it seems to show a third perspective.

The tools that will be your friends in this are layers, the vanishing point filter and the clone stamp tool.

For the floor area use the vanishing point filter and clone within the filter to address the centre diagonals and the fall off of the shadows. By using vanishing point the cloning will stay in perspective.

The white centre can be copied from one of the others and simply stretched to fit the bigger gap.

For the roofbars - copy them onto new layers by selecting each - then transform them to fit the correct perspective. You can use the healing brush onto a new layer to get rid of the old bars.

I have done a quick and dirty example below - which still needs some work, to blend fully - e.g. the centre roof shade needs a bit more with a light brush on low opacity to get it to blend,  but this should get you on the right path

I hope that helps get you started
I will be offline shortly (it is late in the UK) but can pick up any questions tomorrow.

Have fun

Dave