Computers, installation and licences

HVS Image Video Tracking runs on almost any PC-compatible computer. HVS recommends a new computer with Windows 11 (Windows 7, 8 or 10 also work), an i3 or better CPU and 8 GB RAM or more; systems are usually supplied with 8 or 16 GB RAM and 1 TB or more of disc. If the computer must also be used for other work, it should be high specification and set up to dual boot from a partitioned drive so that no background processes run while you track.

Going deeper

Acquisition is the demanding part: background processes steal processor time and cause dropped points (seen as straight lines on path plots). The dual-boot advice keeps a clean tracking installation. Analysis can run on additional computers where specification matters less; faster PCs simply process large batches or long trials more quickly. VR systems have separate requirements (contact HVS).

The HVS accessory kit is usually included with your system. It contains the HVS Image USB camera (which, unlike a webcam, accepts different lenses for set-ups from a small open field to a large water maze), a boosted USB extension cable for the camera, a ceiling mount and a long-range wireless remote for starting and stopping trials away from the computer. With a student licence and no kit you need a suitable mouse, camera and extension lead of your own.

Going deeper

If you supply your own parts, follow HVS's requirements for the remote/mouse (reliable single click, about 10 m range), camera and boosted extension lead (active repeater type, plugged into a USB 3 port).

The HVS Image LabCam is recommended because it takes lenses to suit your lab, but the software runs with a large range of USB webcams; even a basic Microsoft LifeCam gives good resolution, gain control, linearity and frame rate. Where the tracking area is large and the camera cannot fit the pool surface in the image, contact HVS. Only one program can use the camera at a time, so close any webcam software before starting HVS Image.

Going deeper

Lens choice depends on pool or maze diameter and the ceiling-to-surface distance; for water maze, varifocal lenses are not normally needed and 2.8 mm or 2.1 mm lenses suit typical rooms. HVS asks for the water-surface diameter and ceiling-to-water distance to supply a correctly lensed camera. Only the water surface must be in view; cutting off the pool rim is fine.

You can run the camera 10 m or more from the PC with the correct boosted USB lead: a 10 m USB Active Repeater Hi-Speed extension cable. Plug it into a USB 3 port (blue inside). Contact HVS if you need a greater length.

Going deeper

Unboosted passive extensions lose signal over long runs and cause camera connection errors. A laptop on battery near the pool also gives electrical isolation from mains in wet rooms.

Other software can take a fraction of a second or more away from real-time data acquisition, so the tracking (or VR) PC should be dedicated to HVS Image with no other software installed. HVS recommends: turn off antivirus and other scanning programs (using their own settings); turn off Windows Update and automatic updates for other software; use Task Scheduler to stop or disable other background tasks during tracking times; and create a new power plan based on 'High Performance' with USB suspend disabled (so the camera link is not cut), adaptive brightness off, the hard disk staying on, Sleep and Hibernate set to Never and hybrid sleep allowed. Run scans and updates manually when no tracking is planned. Disable any built-in webcam in Device Manager. Excel and other software are fine on a separate analysis PC.

Going deeper

Symptoms of background interference seen in support cases: the trial clock freezing, frames dropping, tracking lost briefly, and straight lines on path plots (often towards the top-left). Use Task Manager to end unneeded tasks and disable unneeded start-up apps; HVS can liaise with your IT department over security scans. If you need the PC for other work, dual boot from a partitioned drive and run HVS from drive C:. Setting User Account Control to 'Never notify' avoids the prompt each time the software starts. The RUN system check also warns if background processes make the PC unsuitable.

To get a code, click RUN (or the relevant module) and send HVS the red code shown via the Support button or contact page; tracking, analysis and video frame recording are activated separately. Pasting the Run code in Analyze won't work. If the Analysis activation box appears with the Run code, click End and restart, then paste the Analyze code in the red box. No internet connection is needed for activation, so offline PCs are fine. A new computer needs new codes from HVS; analysis that stops being activated is fixed with a new Analysis code.

Going deeper

A temporary activation key may be issued before an ongoing key; paste the ongoing key when prompted. Never share activation codes publicly. Encrypting the tracking computer can cause problems; free support assumes the system as supplied.

HVS gives remote help free of charge: click the Support button on the HVS main menu, which opens a new email to HVS support, and HVS can then connect to your tracking PC through a remote-desktop session, with your permission, to view it or operate it. Sessions can be view-only. HVS can also see the lab set-up through the tracking camera. Remote sessions currently use RustDesk: install it from its official release page and give HVS the session details privately. Never post remote-access IDs or passwords in shared documents.

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For checking tracking or calibration remotely, set up as for experiments (water at experimental level, lighting on, animals available).

Error 53 on Master Experiment Files or Analyze means program files were moved or deleted; reinstalling puts them back. Error 76 (Path not found) is also fixed by reinstalling the latest build as administrator. 'Files didn't register during installation' is fixed by re-running the installer as administrator, or by manual registration in a remote session. Check version and build via the About button on the main menu.

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A download that does nothing on Run: choose Save, then right-click the saved file > Run as administrator.

Each version has its own folder, so after an upgrade copy data across. Newer versions analyse old .hvs raw data. Install over an existing version (no uninstall needed) after backing up data and videos.

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Software updates are provided on request: contact HVS for a link to the right version.

There is no known limit on users; watch disk space. Advanced settings such as counter diameter persist per user. Rename data files in the HVS folder with right-click > Rename. Back up often; keep all .hvs files (SUM and CST can be recreated from them), and move finished files elsewhere (they then no longer show).

No: HVS Image is Windows software and does not run natively on macOS. It has been run on a Mac under Windows via Boot Camp on Intel Macs; on newer Macs you would need a Windows virtual machine, which HVS has not tested.

Going deeper

Exported results are ordinary comma-separated files, so once trials have been analysed on Windows you can open the results on a Mac in Excel or any statistics package.

Yes: HVS Image has a path plots app for Android phones that shows the path plots from your .hvs trial files, so you can browse, star and share them away from the tracking PC. The app was supplied as an install file, with a store listing planned. Copy the .hvs files from the tracking system to a location the phone can browse.

Going deeper

The app displays plots only; analysis and exported measures still come from HVS Image on the PC. Ask HVS for the current install file.

The HVS Image software and systems can be used for experiments with subjects of many sizes, such as drosophila, spiders, bats, rodents and much larger animals. The 'Open Field and NOR' module (zone analysis) also covers 48 and 96 well zebrafish larvae plates (and 1, 4, 9, 16 or 25 wells). For any other use, contact HVS.

Going deeper

For well plates, square wells are easiest: the tracking area runs from the top-left corner of the top-left well to the bottom-right of the bottom-right well. Bespoke development is available for custom paradigms.