Inspect images in the viewer
Use the embedded viewer to move through a study, adjust image presentation, and inspect DICOM metadata without changing the source files.
Open the dataset
Section titled “Open the dataset”Launch one or more files or directories:
dcmview ./series ./additional-image.dcmDiscovery is progressive. The viewer can show the first valid object before a large recursive scan finishes. The status bar reports accepted, skipped, and filtered counts.
Use Explorer to switch between clinical Study/Series organization and directory organization. Up/Down arrows move through the active Explorer ordering, including its current filter.
Move through images and frames
Section titled “Move through images and frames”Related single-frame, multiframe, and concatenated objects can appear as one logical stack. Navigation resolves each logical position back to its actual source file and zero-based source frame, so tags, caches, references, and annotations stay attached to the correct object.
| Action | Input |
|---|---|
| Previous or next file in Explorer | Up/Down arrows |
| Previous or next logical frame | Left/Right arrows or [ / ] |
| Move through frames | Mouse wheel |
| Play or pause cine | Space |
| Select cine speed and direction | Frame controls below the viewport |
Cine supports loop and sweep playback. Moving between frames preserves zoom and pan; switching to a different file resets the transform.
Adjust image presentation
Section titled “Adjust image presentation”| Tool | Shortcut | Behavior |
|---|---|---|
| Window/level | W |
Drag to adjust grayscale presentation. |
| Pan | P |
Drag the image without requesting another frame. |
| Zoom | Z |
Drag to zoom; right-drag always zooms. |
| Scroll | S |
Drag to move through the logical frame stack. |
| Reset | Double-click | Restore the viewport presentation. |
Middle-drag always pans. Ctrl/Cmd+wheel zooms instead of changing frames. The toolbar also provides horizontal and vertical flips, 90-degree rotation, DICOM window defaults, full dynamic range, and common CT presets.
Window selection follows this order:
- Full dynamic mode uses the current frame’s minimum and maximum.
- An explicit window/level adjustment.
- DICOM Window Center and Window Width.
- A current-frame 1st/99th percentile fallback.
The viewer normally uses decoded raw samples for responsive windowing when the browser can safely reproduce the server presentation pipeline. It falls back to server-rendered PNGs for layouts or presentation steps that are unsafe to approximate in the browser.
Inspect tags and references
Section titled “Inspect tags and references”Open Tags to filter the lazy tag tree, expand sequences, resize columns, and copy values. Binary values such as Pixel Data are represented by byte length instead of embedding the full payload.
The reference navigator shows typed DICOM relationships. When the referenced SOP instance is present in the current scan, select a validated target to open its file and frame. Unresolved references remain visible rather than being silently discarded.
Use semantic and WSI context carefully
Section titled “Use semantic and WSI context carefully”SEG, Parametric Map, and RT Dose objects expose an opt-in semantic panel beside the unchanged stored-pixel preview. The panel can summarize declared segments, Real World Value Mappings, dose scaling, geometry, and resolved sources. It does not establish clinical interpretation.
For SEG, select Semantic Context to compose the mask over its resolved local source image. Explicit derivation references are preferred; declared-source patient geometry can also resolve classic single-frame source series. Compatible source and SEG matrices may differ in size because the mask is resampled through patient coordinates.
Composition is available only when one source frame and one compatible transform are validated. When identity or geometry is missing, ambiguous, non-coplanar, or non-overlapping, the viewer explains why the overlay is unavailable instead of guessing. ROI editing, interactive window/level, and cine are disabled until you return to Pixel Preview.
RT Dose continues to report overlay eligibility and geometry context without composing a dose overlay.
For Whole Slide Microscopy, the context panel positions the selected tile within the declared Total Pixel Matrix and reports row, column, optical path, focal plane, companion objects, and a minimap. dcmview does not stitch adjacent tiles or reconstruct a slide-wide image.
Stop the viewer
Section titled “Stop the viewer”Return to the launching terminal and press Ctrl+C. The HTTP server, memory caches, and unexported ROI edits are discarded.
For exact controls and support states, see DICOM and pixel support and the CLI reference.