Script

The Script uses Lua 5.1 in order to read or modify header keys of the I/O. E.g. The dimension of an image stack can be read into a Variable by the Script and used as a factor in a different logic like BoxManipulation.

To add or modify header values with the Script it is necessary to connect the I/O of the logic to the Flow Control element Script. By double clicking on the graphic element Script a new window opens. This is the editor to write the Lua script. The advantage of the editor is that is show the Lua syntax highlighting. Another possibility to edit the script is in the properties window.
In order to access a single image in a Cow workflow the Lua script needs to have the following syntax cow.io[#number of the image in the I/O]. Then to read a header value of that image the script needs to be expanded by the name of the header in quotation marks [“image header value name”].

cow.VariableName = cow.io[number of the image in the IO]["image header values name"] 

Example

cow.AngleBeta = cow.io[0]["eulerBeta"] 

Saves the Euler angle Beta of the 0-th image in the I/O to the Variable AngleBeta.

cow.dimension = cow.io[100]["dimX"] 

Saves the dimension in X of the 100-th image in the I/O to the Variable dimension.

cow.dimension = cow.io[cow.iter]["dimX"] 

Saves the dimension in X of the i-th image in the I/O to the Variable dimension. It is necessary to set up a iteration Variable, which is incremented by Calculate.

To overwrite the header value in the I/O

temporary variable name                             = cow.io[number of the image in the IO]
temporary variable name["image header values name"] = new value
cow.io[number of the image in the IO]               = temporary variable name 

Example

temp         = cow.io[0]
temp["dimX"] = 100
cow.io[0]    = temp  

Manipulates the header value dimX of the 0-th image in the I/O. The header dimX is set to 100.

temp         = cow.io[100]
temp["dimX"] = cow.dimension
cow.io[100]  = temp  

Manipulates the header value dimX of the 100-th image in the I/O. The header dimX is set to the Variable dimension.

To write new header values to the I/O

temporary variable name                                = cow.io[number of the image in the IO]
temporary variable name["new image header value name"] = new value
cow.io[number of the image in the IO]                  = temporary variable name 

Example

temp                 = cow.io[0]
temp["linearFactor"] = cow.factor
cow.io[0]            = temp 

Writes the new header value linearFactor for the 0-th image in the I/O. The header linear Factor is set to the Variable factor.

Manipulate the whole I/O
If each image in the I/O is supposed to be manipulated by its header value, the Script needs to be extended by the Flow Control elements Queue, Calculate and an additional iteration Variable.

cow.VariableName = cow.io[cow.IterationVariableName]["image header values name"]

Properties Window

Properties Window

Properties Window

The Script elements works withLua 5.1 Reference Manual. In the following link all Lua functions are listed at the end of the page.