Watershed segmentation for large-scale images

OTB Usage
1

Hello,

I am looking to do a watershed segmentation for a large image. I know that OTB has the LSMS algorithm which handles the tiling artefacts well.

Is there a similar version of the large-scale watershed segmentation algorithm, that segments on tiles, but cleans up the edge artefacts in the vector output?

Best wishes,
Jen

2

Hello,

One of the available algorithm in the Segmentation application is watershed. In vector mode there is the -mode.vector.stitch bool option that try to clean up edge artifacts.

Cédric

3

Hi Cédric,

Thanks - I have successfully managed to get the algorithm to run.

Could you kindly provide the reference to the specific watershed algorithm that was implemented in OTB? The documentation in the cookbook is quite light.

Many thanks
Jen

4

Hello Jen,

OTB uses ITK implementation of the watershed algorithm. You can have a look at ITK software guide. There is several implementation of watershed in ITK, the one we use is itk::watershedImageFilter

There is also this paper from the insight journal discussing the different implementations of watershed in ITK. In this paper, the algorithm we use is referred as “ITK watershed”.

Cédric

5

I think that Depth Threshold and Flood Level should be better defined in the OTB manual and that the 2 references you provide here (in particular de 1st one) should also be included.