VV: Write Image (ITK) fully V&V'ed

src/Plugins/ITKImageProcessing/docs/ITKImageWriterFilter.md

@@ -6,7 +6,11 @@ ITKImageProcessing (ITKImageProcessing)
 
 ## Description
 
-This **Filter** will save images based on an array that represents grayscale, RGB or ARGB color values. If the input array represents a 3D volume, the **Filter** will output a series of slices along one of the orthogonal axes.  The options are to produce XY slices along the Z axis, XZ slices along the Y axis or YZ slices along the X axis. The user has the option to save in one of 3 standard image formats: TIF, BMP, or PNG. The output files will be numbered sequentially starting at zero (0) and ending at the total dimensions for the chosen axis. For example, if the Z axis has 117 dimensions, 117 XY image files will be produced and numbered 0 to 116. Unless the data is a single slice then only a single image will be produced using the name given in the Output File parameter.
+This **Filter** will save images based on scalar, vector, RGB, or RGBA values. Supported component counts are 1, 2, 3, 4, 10, 11, and 36. If the input array represents a 3D volume, the **Filter** will output a series of slices along one of the orthogonal axes. The options are to produce XY slices along the Z axis, XZ slices along the Y axis or YZ slices along the X axis.
+
+The available output formats are determined by the installed ITK image I/O backends and the filename extension. TIFF, BMP, and PNG are common 2D choices; not every pixel type is supported by every format.
+
+For a series, the *Output File* stem is followed by an underscore and the slice index. *Index Offset*, *Total Number of Index Digits*, and *Fill Character* control the first index and its formatting. For example, with 117 Z cells, offset *0*, width *3*, and fill character `0`, the XY output files are named `slice_000.tif` through `slice_116.tif`. A single-slice output keeps the exact name supplied in *Output File*.
 
 An example of a **Filter** that produces color data that can be used as input to this **Filter**
 is the {ref}`Generate IFP Colors <OrientationAnalysis/ComputeIPFColorsFilter:Description>` **Filter**, which will generate RGB values for each voxel in the volume.