Strategy for trimap definition

[theponpon]

Hi,

First thank you for this very interesting work!

I am trying to use it on my own images
The objective is to separate the object from the table on which it is laying.
I also have a way to identify most of the object from the geometry, so I make it the white area of the trimap
I have a way of identifying the table with some thickness from the geometry so I make it part of the gray area of the trimap
Finally I know that all the rest is background set to the black area of the trimap

When applying this approach to the sample image below, the results are disappointing:

Is my gray area strategy correct?
Are there any finetuning settings I could use?

Any advice from you would be greatly appreciated!

Regards,

Pierre

[pgt4861]

hi, thank you for your interest on our work.
I think the best way to draw trimap for separating the object (a cup) from the table is like below.

In image matting problem, unknown (gray) region usually lie on boundary or transparent region of the object (or stuff).
thank you