Documentation

Videre is a browser-based camera evaluation tool for Linux. It connects to any V4L2-compatible camera and streams live video to your browser — no desktop environment, no Qt, no Electron required.

Installation

Videre ships as a single self-contained binary. Download the package for your system from the Community download page.

Runtime dependencies

The .deb and .AppImage bundles include all dependencies. For tarball installs, the following libraries must be present:

First Run

Videre starts a local web server and opens your default browser automatically. Navigate to http://localhost:8080 if it doesn't open. The port is printed to the terminal on startup; use --port PORT to change it.

To control which browser is launched, or to suppress it entirely:

--browser accepts any command on $PATH. The default is xdg-open.

Interface Overview

Connecting a Camera

1. Click the sidebar toggle (chevron, top-left) to open the device list.
2. A list of detected V4L2 devices appears (e.g. /dev/video0). Click a device to open it.
3. The sidebar shows the device name when connected.
4. Click ▶ Play in the toolbar to start streaming.

The status bar shows live FPS and resolution once streaming starts. If the camera disconnects, an error banner appears and streaming stops automatically.

Pixel format and frame size can be changed in the Control Panel while not streaming. Stop the stream first — there is no need to close the camera. The new format takes effect when you press Play again.

Camera Controls

The Control Panel (right side) exposes every parameter reported by the V4L2 driver, rendered as sliders, checkboxes, menus, or buttons depending on type. Exposure and Gain sliders refresh ~3 times per second to reflect the current driver value when Auto mode is active.

Primary controls

Additional controls

All other V4L2 controls reported by the driver (sharpness, saturation, hue, power-line frequency, backlight compensation, and any camera-specific controls) appear below the primary controls, automatically discovered at open time.

Format and resolution

Discrete cameras (most USB webcams) show a drop-down list of preset resolutions.

Stepwise / continuous cameras (industrial, machine-vision) support arbitrary resolutions within a range. Two number inputs appear instead of a drop-down — enter the desired width and height; the hint below shows the valid range and step size (e.g. 640–1920 × 480–1080 (step 2×2)). Click Apply to set it.

Display Rate

The Display Rate section in the Control Panel (visible while streaming) controls how many frames per second are forwarded to the browser, using adaptive decimation.

After each second of streaming, Videre computes a decimation factor so the browser receives approximately the target FPS. For example, if the camera captures at 120 fps and the target is 30 fps, 1 in every 4 frames is forwarded.

Zoom & Flip

Zoom

Zoom is display-only and has no effect on saved images or recordings.

Flip

Flip H / Flip V mirror the image horizontally or vertically. Flip is display-only — saved images and recordings are not affected.

Crop / ROI

Videre probes each camera at open time to determine which crop mode it supports and labels the UI accordingly. Three modes exist:

When a hardware crop or UVC ROI is active, a Reset H.Crop or Reset ROI button appears in the toolbar. The camera driver may adjust the selected region to align with sensor boundaries; the status bar shows the actual applied dimensions.

The Advanced section of the Control Panel also exposes crop/ROI coordinates as number inputs for precise entry.

Saving Images

Click the Camera icon in the toolbar. The current frame is saved immediately to ~/Pictures/videre/ with a timestamp filename (e.g. 20260222_143512_042.jpg).

Select JPEG or TIFF as the default in Settings (gear icon). When image processing filters are active, all save formats operate on the filtered frame.

Recording Video

Click Record in the toolbar to start; click again to stop. Files are saved to ~/Pictures/videre/ as AVI.

A maximum file size limit (default 200 MB, configurable in Settings) stops recording automatically. The AVI container uses a nominal 30 fps timestamp — playback speed will differ if the camera runs at a different rate. Recordings capture every frame regardless of the display rate / decimation setting.

Image Mode

Image mode lets you load a still image file for offline analysis using the same tools available for live streams — histogram, ROI analysis, image processing filters, and detectors. No camera is required.

Loading an image

Click the Load Image button in the toolbar. A panel appears with two loading methods:

Supported formats: JPEG, PNG, TIFF, BMP, and camera RAW files (DNG, CR2, CR3, NEF, ARW, ORF, RW2, and others via LibRaw). RAW files take 1–5 seconds. To return to camera streaming, click the ✕ next to the filename.

Render modes (RAW files only)

Analysis tools in image mode

Histogram, ROI analysis, image processing filters, and detectors all work identically on the loaded image. Changing the render mode or Filmic sliders re-renders in place — no "apply" button needed.

Settings

Click the gear icon in the toolbar to open the Settings panel.

Live Histogram

Click the Histogram (bar chart) icon in the toolbar to toggle the overlay. The panel appears in the lower-left corner of the viewport, and is freely moveable and resizable.

Channels

Each channel has an independent toggle (L / R / G / B). Disabling a channel removes it from the display and from the auto-scale calculation — remaining channels fill the full height.

Moving and resizing

Scale, Axes, and Crosshair

Toggle between Log (default) and Lin scale in the panel header. Log scale makes shadows and dark tones easier to read.

Click Axes to overlay axis labels: Y-axis (max count / 0), X-axis (0, 128, 255), and faint grid lines at 25%, 50%, and 75% positions.

Move the mouse over the histogram canvas to show a vertical crosshair. A tooltip displays the pixel value (0–255) at the cursor and the count for each visible channel, updating live during streaming.

Clipping indicators

• Red vertical line at the right edge — highlight clipping (pixels at 255)
• Blue vertical line at the left edge — shadow clipping (pixels at 0)

Image Quality Analysis

Click Analyze in the histogram footer to collect 5 seconds of data at up to 60 samples/sec. A progress bar shows collection status. After collection, the analysis dialog reports:

ROI Analytics

Right-click the live viewport and select Analyze, then click and drag to draw a region. The ROI Analysis panel appears and begins updating automatically.

Statistics

Per-channel statistics are computed over all pixels in the selected region:

For colour cameras values are in the 0–255 range across R, G, B, and luma channels. For mono cameras (GREY / Y16) analysis runs at native bit depth — a single Mono row is shown with values in the sensor's native range (e.g. 2048 / 4095 for a 12-bit source).

Line profiles

Two colour-coded canvas charts show pixel values sampled from within the ROI. Use the H / V tab buttons to switch between horizontal and vertical profiles. Each channel (R, G, B, luma) can be toggled independently.

The panel polls every 250 ms while streaming. Moving or resizing the selection box updates statistics immediately on mouse release. Close with the × button to stop polling.

Pixel Filters

The Processing section in the Control Panel provides a per-frame OpenCV filter chain. Filters run sequentially in a dedicated processing thread and can be toggled while streaming — changes take effect on the next frame.

Filters are applied in the order shown. Multiple filters can be active simultaneously — each is applied to the output of the previous one. When filters are active, histogram computation, saves, and recordings all operate on the filtered frame.

Shape Detectors

Detectors run after the pixel filter chain, concurrently across available CPU cores. Enabling multiple detectors does not multiply latency.

Overlay vs. Burn-in

Tips

• Stack a Gaussian Blur before a detector to reduce noise-induced false positives.
• Canny Edges followed by Contour Detector (mode = all) finds edges and their regions together.
• Area limits (minArea / maxArea in pixels²) are the most effective way to filter out noise and out-of-scale objects.
• For Circle Detector, lower Param 2 finds more circles but increases false positives.

Barcode & QR Scanner

Enable the Barcode Detector (ZBar) in the Detectors section. Each found symbol is highlighted with a yellow polygon overlay and labelled with its type and decoded text (e.g. QR-Code: https://...).

Supported symbologies: QR Code, EAN-13/8, UPC-A/E, Code 128/39/93, DataBar, ITF, and more.

Hardware Diagnostics

Open via Settings → Performance Diagnostics → Open, or navigate directly to /diagnostics. No root access required — all data is read from sysfs/procfs.

System Information

Camera / USB

Recommendations

Common recommendations include: disabling USB autosuspend (with the exact sysfs command to run), USB 3.0 suggestions when bandwidth utilisation exceeds 80%, hardware crop / UVC ROI capability notes, and adjustable frame rate range information.

Live Pipeline Metrics

While streaming, the page polls every second and shows average and peak timing for each processing stage, plus a bar chart relative to the frame budget (1000 / device FPS):

Total, Budget, and Headroom rows at the bottom show at a glance whether the pipeline is on track for the camera's frame rate. Frame counts (processed and dropped, with a drop percentage) are shown below the table.

Usage Data & Privacy

On first launch, Videre shows a consent dialog before camera controls become accessible. Behaviour depends on your license tier.

Community Edition

Anonymous usage data collection is mandatory for the free Community Edition. The consent dialog offers Accept & Continue or Exit. Choosing Exit shows a "usage data required" message and the app does not proceed. After accepting, the app works normally — no further action is needed.

After 1 hour of cumulative use, a verified internet connection is required to continue:

1. A popup appears: "To continue, an internet connection is required for usage data verification — or purchase the Pro version."
2. Three connection attempts are made automatically (immediately, +30 s, +60 s).
3. A 3-minute window is given in total. If any attempt succeeds, the popup is dismissed and the app continues normally.
4. If the window expires without a connection, the app shuts down after 3 seconds.

Cumulative usage is tracked across sessions and stored in ~/.config/videre/config.json. Delete or edit that file to reset the consent decision — the dialog will reappear on next launch.

Paid tiers

Paid tiers (Pro, Subscription, Source) show the consent dialog with Accept & Continue and Decline options. Usage data collection is optional, the decision can be changed in Settings, and no internet connection is required.

What is collected

Feature events fire once per user action, never per frame: histogram, histogram_analyze, roi_analysis, snapshot, recording, filter:gaussian_blur, filter:canny_edges, filter:contour_detector, flip_h, flip_v, crop, zoom_fit, and similar.

Disabling usage data collection

Pass --no-telemetry on the command line to suppress the consent dialog and disable all data collection. This is intended for paid tiers.

Paid License Flow

When a Pro or Subscription build starts without an activated license token, Videre shows a blocking license screen before the main application is accessible.

Options on first launch

Activation credits

Pro licenses include 50 lifetime activation credits. Subscription licenses include 100 activation credits per year (renewed annually). Reinstalling on the same machine typically reuses the existing activation. Major hardware changes may consume another credit — contact support in exceptional cases.

Activation state is stored in ~/.config/videre/license.json. To revoke the current device, use Settings → Revoke License.

Retrieving your license key

After purchase, the purchase-success page shows your license key immediately from the LemonSqueezy redirect. If you no longer have the key, the recovery page at get-videre.com/license-recovery sends an email with a single-use verification link that reveals your key.

Remote Access

SSH port forwarding (recommended)

Forward Videre's port over SSH to access the full web UI from your local machine securely:

This is the recommended approach — the SSH tunnel provides authentication and encryption with no additional configuration.

CLI over SSH

CLI subcommands work naturally over SSH without port forwarding:

Network binding

By default Videre binds to 127.0.0.1. Use --bind to listen on other interfaces:

CLI Reference

Videre includes CLI subcommands that operate without starting the web server — useful for scripting, automation, headless systems, and SSH workflows.

Run videre COMMAND --help for full options on any subcommand.

List cameras

Device info

Capture frames

Capture flags

Capture formats

For raw and native multi-frame captures, a metadata.json sidecar is written with pixel format, dimensions, and per-frame timestamps. When --frames N with N > 1, frames are written to a directory as frame_000001.jpg, frame_000002.jpg, etc.

Record video

Server Options

REST API

Every feature in the web UI is also accessible via HTTP REST and WebSocket — suitable for scripting, automation pipelines, and headless integration.

Full endpoint reference — including WebSocket events, control endpoints, and the diagnostics API — is available in the API Reference.

Pixel Formats

Gray World white balance is applied to all Bayer demosaic paths.

Not yet supported

• YUV 4:2:0 planar (YU12 / YV12)

Raspberry Pi 5

Videre supports Raspberry Pi 5 with CSI-2 cameras using the rp1-cfe driver. Supported sensors include the HQ Camera (imx477), Camera Module 3 (imx708), Camera Module 2 (imx219), and others.

Camera discovery

Raspberry Pi cameras appear in the sidebar as a single logical entry — e.g. "Raspberry Pi HQ Camera (imx477)" — rather than individual /dev/videoX nodes. Videre configures the Linux Media Controller graph automatically.

Pipeline modes

Tuning file selection

On first open in ISP mode, Videre scans /usr/share/libcamera/ipa/rpi/pisp/ for matching .json tuning files and shows a selection dialog. Choose the file that matches your sensor (e.g. imx477.json for the HQ Camera, imx477_noir.json for the NoIR variant). The choice is remembered for the session.

Image Pipeline controls (ISP mode)

Feature status

Limitations