ColorQuantize[image, n] gives an approximation to image that uses only n distinct colors.
ContentPadding is an option for objects that can be displayed with frames that specifies whether the vertical margins should shrink wrap tightly around the contents.
DefaultBoxStyle is a low-level option for three-dimensional graphics functions that specifies the default style to use in rendering the bounding box.
DefaultFaceGridsStyle is a low-level option for 3D graphics functions that specifies the default style to use in rendering face grids.
DefaultFieldHintStyle is a low-level option for InputField that specifies the default style to use for displaying the field hint.
DefaultFrameTicksStyle is a low-level option for 2D graphics functions that specifies the default style to use in rendering frame ticks.
DefaultGridLinesStyle is a low-level option for 2D graphics functions that specifies the default style to use in rendering grid lines.
DefaultLabelStyle is a low-level option for formatting and related constructs that specifies the default style to use in displaying their label-like elements.
DefaultMenuStyle is a low-level option for menu-generating constructs that specifies the default style to use for displaying menu items.
DefaultTicksStyle is a low-level option for graphics functions that specifies the default style to use in rendering ticks.