Exposing "geometry mask"

[IngmarVoigt2]

For certain processing tasks it would be useful to expose a mask of the geometry (i.e. a Cartesian volume of the same size as the actual image data, but only consisting of e.g. 1 or 255 inside the actual Ultrasound scan geometry and 0 outside - illustration below).

For the sake of computational efficiency it would ideally be sampled together with the actual Cartesian volume (containing the anatomy), e.g. via an overload of IImage3dSource::GetFrame( ..., Image3d *geomMask)

Clearly this would involve an interface change, that impacts all plugins, so prb the default implementation could just fall back onto the original IImage3dSource::GetFrame - what do you think @forderud ?

[forderud]

I think it would be even simpler to do the following:

• Update the doc to state Zero-valued tissue samples are special in the sense that they indicate areas outside of the imaging sector.
• Ask all vendors to update their loaders to guarantee that within-image-sector samples are guaranteed to have non-zero sample values.

Still, this proposal will need to be discussed between all vendors first.

[IngmarVoigt2]

That might be one way, but may potentially mess up some of the processing that is in place nowadays - not sure ..