Image & Video Viewer
Overview
The Image & Video Viewer displays 2D and 2Dts signals - single images and image series (videos). It supports interactive pan, zoom, scalebar overlays, colour maps, and data value annotations.
Pan and Zoom
| Action | Control |
|---|---|
| Pan | Click and drag |
| Zoom | Mouse wheel (centred on cursor) |
| Selection zoom | Hold Shift + drag to draw a rectangle |
| Reset view | Double-click |
Scalebar
The scalebar is rendered automatically when the signal contains spatial axis metadata. It adapts its colour (black or white) based on the brightness of the pixels behind it to stay readable on any image.
Supported units
Real-space - m, µm, nm, pm, Å. Values are displayed in the most readable unit (e.g. values ≥ 1000 nm are shown in µm).
Reciprocal-space - 1/nm, 1/Å, 1/m. Displayed directly with the original unit.
Scale values
The bar length is chosen from a series of “nice” values (1, 2, 5, 10, 20, 50, 100, …) so that it is approximately 150 pixels wide at the current zoom level. The label shows the exact length and unit.
Colour Maps
Select a colour map from the Color Scale dropdown in the panel settings (cog icon → Selection tab → Display Options).
| Map | Description |
|---|---|
| Grayscale | Linear black-to-white (default) |
| Viridis | Perceptually uniform, colour-blind friendly |
| Plasma | Purple → yellow gradient |
| Inferno | Dark → bright, perceptually uniform |
| Magma | Dark purple → cyan |
| Jet | Classic blue → red rainbow |
| Turbo | Improved rainbow with more detail |
Annotations Overlay
The image viewer can overlay live values from other signals (e.g. temperature, pressure) directly on the image. These update in real time as you scrub the timeline.
Adding annotations
Drag a 0Dts signal from the Data tab onto an existing Image Viewer panel. The signal appears as a coloured badge in the top-left corner of the image showing the signal name, current value, and unit.
Annotation display
- Each annotation uses the signal’s workspace colour as its accent.
- Values are formatted with automatic precision based on the data range.
- The signal name is shown alongside the value. You can hide signal names via the Annotation Labels toggle in the panel settings.
- To hide all annotations, use the Annotations toggle in the panel settings.
Removing annotations
Hover over the panel and click the × button on the annotation badge to remove it. The signal remains in the workspace - only the overlay is removed.
Frame Navigation
For image series (2Dts), the viewer shows the frame corresponding to the current timeline position. Scrubbing the timeline automatically updates the displayed frame.
Lock Frame
Enable Lock Frame in the panel settings (Frame Navigation section) to freeze the displayed frame. When locked, scrubbing the timeline changes the time position but the viewer keeps showing the same frame.
Smart frame loading
When you drop an image series onto the canvas, Nexus displays the first frame immediately - there is no need to wait for the entire series to finish loading. Additional frames are loaded automatically in the background and on-demand as you navigate the timeline, so playback stays smooth even for large datasets.
The cache indicator on the timeline sparkline shows which frames are ready - taller bars indicate cached frames.