The mark-up attachment allows the user, tools and even external plug-ins to add data to a layer in a simple plain-text (UTF-8) format. The data may then be used for whatever purpose. All elements take the form object.property=value; where property may have sub-properties within it. The data may be edited within the mark-up editor dialog and may be broadcast to other layers. Some implementations may be case-sensitive; it is therefore advised that you observe case.
Common uses for the MARK attachment include adding color depth information to images and capsulating EXIF camera metadata. MARK may also be used for format-specific data, subject to namespace rules.
Below is a list of common mark-up tags:
Namespace or Tag
Details
image.
Reserved namespace for image-data-specific attributes.
image.bpp=x;
This tag is used to define the target color depth, x, in bits per pixel. It is used by the file plug-ins for icons, cursors and BMP images.
image.scaling=x;
This tag is used to define the scaling factor that has been applied to an auto-resized image, in percentage. It is used by file plug-ins that are capable of importing oversized images.
image.original.width=x;
image.original.height=y;
These tags is used to define the original size of auto-resized image, in pixels. They are used by file plug-ins that are capable of importing oversized images.
exif.
Reserved namespace for EXIF data attributes.
exif.tag=value;
These tags are used for EXIF metadata. Element "tag" is a name that corresponds to the EXIF element/tag type and "value" is the value, either a number or string, e.g.:
exif.make=EASTMAN KODAK COMPANY;
exif.model=KODAK EASYSHARE M341 Digital Camera;
It is used by rawPhoto and the JPEG plug-in.
Here is a list of common exif.* elements:
exif.make=text;
exif.model=text;
exif.exposure_time=n/m sec;
exif.date_time_original=yyyy:mm:dd hh:mm:ss;
exif.date_time_digitized=yyyy:mm:dd hh:mm:ss;
exif.aperture=f/n;
exif.ISO_speed=ISO-200;
exif.focal_length=6.79 mm;
exif.focal_length_35mm=28 mm;
exif.flash=n;
exif.color_space=n; 1 for sRGB
exif.GPS.latitude.pos=n; GPS latitude value
brush.
Reserved namespace for brush object attributes.
brush.spacing=x;
This tag is used to control the spacing attribute of a custom brush.
brush.color_mode=mode;
This tag is used to define the color mode of a custom brush. Three modes are supported, color, alpha and mono.
brush.scale_mode=mode;
This tag is used to define the scaling mode of a custom brush. Two modes are supported, smooth and rough.
brush.auto_select=mode;
This tag is used to define the auto-selection mode of a custom brush. Two modes are supported, none and width.
brush.auto_rotate=mode;
This tag is used to define the auto-rotation mode of a custom brush. Three modes are supported, none, vector and user_input.
anim.
Reserved namespace for animation attributes.
anim.group.tag=value;
These are reserved for use by future animation extensions.
file.
Reserved namespace for file-type-specific attributes.
system.
Reserved namespace for system attributes.
core.
Reserved namespace for system attributes.
The
presence of metadata is indicated by a small paperclip next to the layer in the
layers window. The number of attachments is indicated below it. Clicking the paperclip brings up the attachment manager.
The mark-up 