Oil Over The Picture...
Old Colorize...
Old Photo...
Ommadawn...
On &key pressed:
Onde...
Ondulation...
One window per document
Online
Linea
Online help
Only draw outline of basic shapes.
Only high freqencies in the affected region are copied.
Only low freqencies in the affected region are copied.
Only show strings containning the entered character sequence.
Only show the selected layer without effects in the raster editor.
Only the last operation can be undone. This option conserves memory but does not improve performance.
Op Art City...
Opacity
Opacity and image mask
Opacity->Luminosity
Image editors, Image viewers, Icons & cursors, 3D graphics editors, Other applications