Quoted from "ktransform doc"

syntax:
ktransform mode inputfile outputfile [rx ry rz [fov]] [options]


mode ... cube6, hcube, vcube, rotate, view
cube6 = transform to cube panorama images (6 images)
hcube = transform to horizontal cube panorama imagestrip
vcube = transform to vertical cube panorama imagestrip
rotate = rotates a sphere panorama image
view = creates a 2d view from a sphere image

.....

Quoted from "<image type="

......
attributes for left/front/right/back/up/down:

• strip
  Order of the image in the strip (1-6)
  Default values:
  left="1", front="2", right="3", back="4", up="5", down="6"
• rotate
  rotate the image - rotation in degrees, default="0"
• flip
  flip/mirror the image over the X and/or Y axis
  allowed values: "X" or "Y" or "XY" or "none", default="none"

NOTE: tiled or multiresolution cubestrips are not supported

example codes:
<image type="CUBESTRIP">
<cubestrip url="cubestrip.jpg" />
</image>

<image type="CUBESTRIP">
<cubestrip url="cubestrip.jpg" />
<left strip="2" rotate="-90" />
<front strip="1" />
<right strip="3" rotate="+90" />
<back strip="4" />
<up strip="6" rotate="+180" />
<down strip="5" rotate="-180" />
</image>