The parameters which control the model search process are in
the **SmartROI params** dialog box.

- The
**init**facility will reset the variables which define the offest from the mean model to zero. (ie: setting the model a specification back to the mean). - The total number of mark-up points defining the current model
is specified by
**No.Points**parameter. The model supports inner profile points as those points not included in the outer boundary**No.Points**-**No.Outside**. - The
**Profile**parameter specifies the length of the grey-level profile used for modelling. - Location of the model (mid-point of the main axis)
is specified by the
**tx**and**ty**parameters. The search step used during initial localisation in the Simplex algorithm are specified by the**dtx**and**dty**parameters. - The
**scale**and**theta**parameters specify linear axis size and orientation of the current boundary profile. The search step used during initial localisation in the Simplex algorithm are specified by the**dscale**and**dtheta**parameters. Localisation is also restricted to lie withing the specified**s min**,**s max**,**th max**scale and orientation ranges. If the initial scale estimate is outside this range then the routine will not optimise and the location will be returned unmodified. This can often be a source of problem when using the software for the first time and should be watched out for. - The offest shape eigen values are specified by the enumerated variables
together with their search step parameters
**dw**. The effect of changing a parameter can be directly visualised by**redraw**ing the relevant**Tv**. - The initialiseation of the Simplex algorithm is determined
by the
**Initial Search**parameters. Large values will result in quicker but less precise localisation. - The specified model will have
**mdl modes**shape eigen vectors and**prf modes**grey level eigen vectors. A value of zero corresponds to mean value only. - The maximum variation of the model away from the mean
model is limited by the
**Search Limits**.