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Requires Weasis 4.8.0 or later

This page describes a feature that does not exist in the Weasis version selected in the sidebar.

Window/Level presets

Share Window/Level presets with all users

Weasis combines three sets of Window/Level presets since v4.8.0:

Set Where it comes from Editable by users
Built-in delivered with Weasis (the CT presets Brain, Lung, Bone…) no
Site config/windowPresets.json of the resources package, see Configuration documents no
User saved by each user in customWindowPresets.json of the preferences folder; see Window / Level presets yes

The three sets are merged by preset id: a site preset with the id of a built-in preset replaces it, and a user preset replaces a site one — unless the site locked it. Users see the site presets as read-only, marked (site) or (site, locked), in Preferences > Viewer > Window/Level presets and can duplicate them to make their own version; a user preset that overrides a site or built-in one offers Reset to the site preset instead of Delete.

Ship the site document

The site document is config/windowPresets.json of the resources package — resources.zip uploaded in ViewerHub for a release and a group, or app/resources/config/ of a local installation — like the other configuration documents. The package is fetched and cached by the launcher, so the document is always a local file: reading it never waits for the network. A document that cannot be parsed leaves the built-in and user presets available and is reported in the log. The Reload configuration files button of the preferences dialog reads it again without restarting.

Tip

The easiest way to write the document is to create the presets in Preferences > Viewer > Window/Level presets, then export them with ⋯ > Export… (the export holds the user presets only). Rename the ids from user. to site. before publishing the file.

Document format

The document is a JSON object with a schema version and a list of presets:

{
  "schema": 1,
  "presets": [
    {
      "id": "site.ct.liver-portal",
      "name": "Liver portal phase",
      "modality": ["CT"],
      "window": 180,
      "level": 60,
      "domain": {"kind": "absolute", "unit": "HU"},
      "key": "9",
      "when": {"preferBodyPart": ["ABDOMEN"]}
    },
    {
      "id": "site.mr.bright",
      "name": "Bright",
      "modality": ["MR"],
      "window": 60,
      "level": 45,
      "domain": {"kind": "percent", "reference": "series"}
    }
  ]
}
Field Required Meaning
id yes Stable identifier, prefixed site.. Reuse the id of a built-in preset (e.g. weasis.ct.lung) to change it for everyone.
name yes Name shown in the preset list.
modality no DICOM modality codes (CT, MR, PT…), as a list or a single string; absent means every modality.
category, tags no A category name and a list of keywords, kept in the document for your own organization; the viewer does not show them.
window, level yes Window width (greater than 0) and center, in the values given by domain.
domain.kind no absolute (default): modality values after the Modality LUT, e.g. Hounsfield units for CT. percent: percentages of a value range, for images without calibrated values (MR, PET, CR…).
domain.unit no Unit shown with absolute values, e.g. HU.
domain.reference no For percent: image (default), the range of each image, or series, the range given by the series (Smallest / Largest Pixel Value in Series, otherwise the image range).
shape no LUT shape: linear (default), linear-exact, sigmoid (defined by DICOM), sigmoid-norm, log, log-inv (Weasis shapes).
key no Shortcut digit from 3 to 9 (0, 1 and 2 are used by Auto Level and the windows of the image). When two presets offered for an image share a digit, the one of the latest set gets it — user over site over built-in — and the other is reported in the log. The built-in CT presets use 3 to 7.
when.minBitsStored no Offer the preset only from this Bits Stored value; default 9, which leaves out 8-bit secondary captures.
when.requiresRescale no true to offer the preset only for images with a Modality LUT (rescale slope / intercept).
when.bodyPart no Offer the preset only for this anatomy (see below).
when.preferBodyPart no List the preset first for this anatomy; it stays available for other images.
default no true: applied first to images that carry no window values of their own (neither in the file nor in a presentation state).
hidden no true: kept out of the lists. Redefine a built-in id with hidden to remove that preset for everyone (the preset must still have a name, a window and a level).
locked no true in the site document: the user layer can neither replace nor hide the preset. Only the site document can lock.
extends no The id of a preset to start from — another preset of the same document or one of a lower layer, e.g. a built-in id — giving only the fields that change. A field replaces the whole field of the base (when and domain included); extends, id and locked are never inherited.

Anatomy

bodyPart and preferBodyPart accept a list of:

  • an area: HEAD, NECK, CHEST, BREAST, ABDOMEN, PELVIS, EXTREMITY, UPPER_EXTREMITY, LOWER_EXTREMITY, WHOLE_BODY — the Region imaged values of the LOINC/RSNA Radiology Playbook — and SPINE. An area includes all its regions: CHEST also matches a lung, a heart or a chest-abdomen-pelvis image.
  • a Body Part Examined term, e.g. LIVER;
  • a code, e.g. SCT:10200004 (SNOMED CT).

The anatomy of an image comes from its Anatomic Region Sequence, otherwise from its Body Part Examined. Many images record neither: prefer preferBodyPart, which never hides a preset. A value that is none of the above is compared with the Body Part Examined of the image as written, and reported in the log in case it is a typo.