hpreview

Description

hpreview is a fast viewer for HALCON dictionary, deep-learning-model, 3D-object-model, and object files. It browses a folder of HALCON files like an image viewer - step through files with Page Up/Page Down, inspect every value in an expandable tree, and see embedded images rendered automatically, straight from HALCON's own pixel buffer.

Supported files: .hdict, .json (via HALCON's own read_dict), .hobj, .hdl and .onnx (deep learning models), 3D object models (.om3, .dxf, .off, .ply, .obj, .stl, .step/.stp, .pts, .ptx, .xyz, .pcd), images (.png, .tif/.tiff, .jpg/.jpeg, .bmp, .jp2, .ima), and HALCON image sequences (.seq).
Full tree inspection: every key, type, and value - including images, regions, XLD contours/polygons/parallels, and deep-learning-model parameters - discovered generically, not from a hardcoded, version-specific list.
Image and overlay preview: images render directly from HALCON's own pixel buffer (correct handling of HALCON-specific pixel types and reduced domains); regions, contours, polygons, and parallels draw as overlays, alone or combined with an image.
Load tuple values as images: for tuples of filenames, such as those found in deep-learning dataset dictionaries, optionally resolve and preview each referenced image file directly.
Save and export: save the original object with HALCON's own writer (write_object/write_image/write_contour_xld_dxf), or export the rendered preview as PNG/JPG/BMP.
Command-line companion (hpreviewcli) for scripting: dump a file's tree as text, convert between .hdict and .json, or extract every iconic object in a dictionary to disk.
Runs on Windows and Linux (the latter as a self-contained AppImage), and automatically detects and uses whichever HALCON version is currently active on your machine. Windows covers every HALCON release from 18.11 to 26.05; Linux currently covers the 18.11, 20.11, 22.11, and 24.11 Steady Editions, with more added upon request.

hpreview showing an image with region and contour overlays, alongside the object tree

hpreview inspecting a deeply nested HALCON dictionary with mixed data types

Deeply nested dictionaries, all in one tree.

hpreview loading a tuple value as an image, showing a sample from a deep learning dataset

Loading tuple values as images - handy for deep learning datasets.

hpreview inspecting the layer parameters of a HALCON deep learning model

Inspecting a deep learning model's (.hdl) layer parameters.

hpreview stepping through multiple objects, with zoom level kept between images

Multi-object stepping - zoom level is kept between images.

hpreviewcli running on Linux, extracting iconic objects

hpreviewcli on Linux: extracting iconic objects.

hpreviewcli running on Linux, dumping a dictionary and extracting iconic objects

hpreviewcli on Linux: dumping a dictionary and extracting objects.

hpreviewcli running on Windows, dumping a dictionary and extracting iconic objects

hpreviewcli on Windows: dumping a dictionary and extracting objects.

hpreview inspecting the layers of an ONNX deep learning model

Inspecting an ONNX deep learning model.

HALCON is a trademark of MVTec Software GmbH. hpreview is an independent product and is not affiliated with or endorsed by MVTec.

Version History

1.1 (released 2026-09-18)

Highlight: hpreview gets a proper Find.

ONNX (.onnx) deep learning models now open directly, right alongside .hdl - the same generic handle-introspection tree, no second-class treatment. (HALCON's own ONNX import limits still apply: opset <=13, float32 tensors only, a subset of operators.)
Find (Ctrl+F): a search bar with a live match count, highlight-all, a regex mode, and separate key/value scoping - including an opt-in uncapped search past the default 1000-element display limit. Matches jump to and expand collapsed nodes automatically; the tree also gained Expand All/Collapse All.

1.0 (released 2026-09-17)

Highlight: hpreview goes cross-platform. Linux is now a first-class citizen, right alongside Windows.

Full Linux support, shipped as a self-contained AppImage - download, mark executable, run. No installer, no dependencies to hunt down.
"Try loading tuple values as images" now also resolves .hobj files and paths without an extension, not just the obvious image formats.
A new File > Open Recent menu remembers where you've been.
Zoom and pan settings are kept when switching across same-size images.
Types display their real HALCON subtype (xld_poly, region, ...) instead of a generic object.
Dozens of smaller fixes: expandable truncated values, reliable Ctrl+C copying, and a fully rewritten help page and EULA.

0.9 (released 2026-08-22)

Highlight: full region and contour visualization arrives.

Region and contour handling gets a full pass: visualize and save XLD polygons and parallels, export as DXF, and see genuine value summaries instead of placeholders.
Generated an SPDX Software Bill of Materials, ahead of the EU Cyber Resilience Act.
Rebuilt on Qt 6.11.2.
Reload the open file with F5.

0.8 (released 2026-08-20)

Highlight: hpreview's first public preview.

The core viewer: browse HALCON dictionaries, images, regions, and contours, with zoom, pan, and a live pixel readout.
Deep-learning-model (.hdl) inspection joins .hdict, .json, and 3D object model support.
hpreviewcli arrives: the same tree-walking, dumping, and extracting power from your terminal or CI pipeline.
Built from the start on a multi-HALCON-version adapter architecture, so hpreview speaks whichever HALCON version is actually installed on your machine - not just one.
Windows file-type association: double-click a HALCON file, and it just opens.

Licensing

hpreview is free to use for evaluation and non-commercial purposes. A license is required for commercial use.

Your license is bound to your machine's HALCON Host ID (the same ID printed on your HALCON dongle and used in your HALCON license file) - to get one, send your name and this Host ID (shown in hpreview's own Enter License... dialog) to hpreview@heindl-solutions.com. We'll prepare and send you an invoice.

A single license costs €800, sold on a business-to-business (B2B) basis only. Need more than one? Get in touch - we offer reduced pricing for multiple licenses.

Once paid, you'll receive a license key by email. Paste it into the Enter License... dialog and press Save - hpreview validates it against your Host ID and saves it automatically.

Moving to a new machine or a different HALCON installation? Your license is tied to that machine's Host ID, so you'll need a new key - just contact us with the new Host ID.

Download

hpreview 1.1 - Windows Installer

hpreview 1.1 - Linux AppImage (x86_64)

Requires a working HALCON installation (any recent version) - HALCON itself is not included and must be licensed separately from MVTec Software GmbH.

On Windows, hpreviewcli.exe is installed right next to hpreview.exe and can be run directly. The Linux AppImage bundles both the GUI and hpreviewcli in one file - running or double-clicking it as-is launches the GUI; to get the CLI instead, create a symlink named hpreviewcli pointing at the AppImage and run that (the standard AppImage convention for picking between bundled binaries), for example ln -sf hpreview-1.1-x86_64.AppImage $HOME/bin/hpreviewcli - with $HOME/bin on your PATH, hpreviewcli <file> then works from anywhere.