OMERO.iviewer settings

Max projection byes

OMERO limits the size of Z-projections to reduce load on the server.

The limit is defined as the number of bytes of raw pixel data in a Z-stack and

the OMERO.server default is equivalent to 1024 * 1024 * 256 bytes.

For example, a single-channel 8-bit image (1 byte per pixel) of XYZ size

1024 * 1024 * 256 is equal to the default threshold.

To double the limit, use::

$ omero config set omero.pixeldata.max_projection_bytes 536870912

If you wish to set a threshold for iviewer that is *lower* than for the server:

$ omero config set omero.web.iviewer.max_projection_bytes 268435456

NB: Z-projection is not supported for tiled images in OMERO

(Images larger than 2048 * 2048 pixels per plane are tiled in iviewer).

Roi color palette

OMERO uses Spectrum Color Picker for selecting ROI colors.

The roi_color_palette option allows you to specify a grid of colors for users to choose for ROIs.

Define rows with brackets, and use commas to separate values. By default, only the first color of each row is shown.

A full grid is shown when the default color picker is hidden (see below)

To define a color palette use::

$ omero config set omero.web.iviewer.roi_color_palette "[rgb(0,255,0)],[darkred,red,pink],[#0000FF]"

To hide the default color picker (and show a grid for the color palette), set show_palette_only to true

You must define a palette and each row can display 4 colors::

$ omero config set omero.web.iviewer.show_palette_only true

Enable mirror

When working with other images (coregistering MRIs for example), it is necessary to be able to mirror an image.

There is now experimental support for runtime image mirroring. To enable mirroring set enable_mirror to true.

$ omero config set omero.web.iviewer.enable_mirror true

Max active channel

By default, iviewer limits the maximum number of active channels to 10. Rendering high numbers of channels

at once puts increased load on the server and it is rarely necessary to visualise more channels at once.

If the iviewer is using the [image region microservice](https://github.com/glencoesoftware/omero-ms-image-region)

then it will use the `max-active-channels` configured there, which is also 10 by default.

$ omero config set omero.web.iviewer.max_active_channels 20

ROI page size

The pagination page size for the ROIs list is 500 by default. Loading larger numbers will take longer.

The pagination is also constrained by the underlying `omero-web` JSON API, so you need to set both these

settings if you want to increase the limit.

$ omero config set omero.web.iviewer.roi_page_size 1000

$ omero config set omero.web.api.max_limit 1000