Orientation#

Plugin Availability

The plugin will be visible when at least one viewer is available.

Control image display orientation and alignment.

Note

This plugin was previous called “Links Control”.

Description#

This plugin is used to align image layers by pixels or sky (WCS). All images are automatically linked by pixels on load but you can use it to re-link by pixels or WCS as needed.

For WCS linking, the “fast approximation” option uses an affine transform to represent the offset between images, if possible. This method, although less accurate, is much more performant and should still be accurate to within a pixel for most cases. If approximation fails, WCS linking will fall back to the full transformation.

Since Jdaviz v3.9, when linking by WCS, a hidden reference data layer without distortion (labeled “Default orientation”) will be created and all the data would be linked to it instead of the first loaded data. As a result, working in pixel space when linked by WCS is not recommended. Additionally, any data with distorted WCS would show as distorted on the display. Furthermore, any data without WCS can no longer be shown in WCS linking mode.

For the best experience, it is recommended that you decide what kind of link you want and set it at the beginning of your Imviz session, rather than later.

For more details on linking, see Linking of datasets in glue.

Key Features:

Rotate images
Flip horizontally/vertically
Align North up, East left
Apply to single or all viewers

Image Rotation#

When linked by WCS, sky rotation is also possible. You can choose from presets (N-up, E-left/right) or provide your own sky angle.

Warning

Each rotation request creates a new reference data layer in the background. Just as in Importing Data into Imviz, the performance would be impacted by the number of active rotation layers you have; only keep the desired rotation layer. Note that the “default orientation” layer cannot be removed.

UI Access#

Click the Orientation icon in the plugin toolbar to:

Select rotation angle
Toggle flip options
Click Align North Up for WCS alignment
Apply to specific viewers or all

API Access#

plg = imviz.plugins['Orientation']
plg.rotation_angle = 45  # degrees
plg.align_by_wcs()  # North up, East left

API References#

Only the following attributes and methods are available through the public plugin API:

show()
open_in_tray()
close_in_tray()
align_by (SelectPluginComponent)
wcs_fast_approximation
delete_subsets()
viewer
orientation
rotation_angle
east_left
add_orientation()
set_north_up_east_left()
set_north_up_east_right()

For detailed API documentation, see Orientation.