Policy attributes and properties of image variants.
| Control | Description | Options |
|---|---|---|
| Priority | Specifies which image properties MCS and MAP should preserve, if possible, if there is no variant/format matching the device capabilities that can handle all image properties. The value of 'Transparency' indicates that formats supporting transparency are preferred over those that do not support it; 'Pixeldepth' means that formats with more color depth are preferred over those with less color depth. This attribute can be overridden for a specific image using the param element. Refer to the topic entitled References to media for further information. | Pixeldepth, Transparency |
| Width Hint | Percentage of the pane to be used by the image. Required if Criteria is 'Generic'; otherwise optional. | |
| Encoding | Encoding of the variant | BMP, GIF, JPEG, PJPEG, PNG |
| Pixel Depth | Color depth in bits of an image pixel | |
| Rendering | Rendering for the image | Color, Monochrome |
| Width | Width in pixels of the image to be displayed | |
| Height | Height in pixels of the image to be displayed | |
| Transparency type | Specifies whether the image is transparent or not, and if so, the type of transparency. This option should be set for 24-bit PNG images because some devices cannot display 24-bit PNG images with alpha channel transparency. It is the page author's responsibility to provide a fallback variant for such images, for example an 8-bit PNG image. 'Unknown' indicates that the page author does not know whether the image is transparent or not, or does not know the type of transparency; 'Alpha' indicates alpha channel transparency; 'Binary' indicates binary transparency; 'none' means that the image is not transparent. | Unknown (default), Alpha, Binary, None |
| Conversion mode | Whether or not the image should be passed to MAP for transcoding. If you select 'Always convert', the image will be converted and you can set cropping values. 'Never convert'(default) disables the crop controls. | Always convert, Never convert |
| May crop before | Inclusive left pixel value to include when cropping a convertible image | |
| May crop after | Inclusive right pixel value to include when cropping a convertible image | |
| Icon composing mode | An optional parameter that indicates whether or not the device should apply any device-specific transformations to the image, e.g. the target device may add a glossy overlay to the image. Refer to the topic entitled Associating an icon with a page for further information. | Allow native, Prefer native, Disallow |