Live Video Capture
Live Video Capture lets you stream directly from a connected camera and serve the footage over a local HLS (HTTP Live Streaming) network. This enables real-time playback in Tagger during an ongoing session, with the stream also available to other devices on the same network.
Live Video Capture is available exclusively in the Tagger Desktop application. It is not available in the web version of Tagger.
Before You Start
Before beginning a live stream, ensure the following:
- You are running Tagger Desktop.
- A compatible video capture device (USB camera, capture card, or built-in webcam) is connected.
- You have a local folder available to store the HLS stream segments.
- No other application (such as Zoom, Microsoft Teams, OBS, or Skype) is actively using the camera.
Setting Up the Stream
Select a Camera Source
- Open the Live Video Capture panel in Tagger Desktop.
- In the Live Stream Source dropdown, select your camera from the list of detected devices.
- If your camera does not appear, click Refresh Cameras to re-scan connected devices.
Select an Output Folder
The HLS stream is written as a series of segment files (.ts) and a playlist file (.m3u8) to a folder on your local machine.
- Click Select Folder next to the HLS Output Folder field.
- Choose a folder on your device where stream files will be saved.
Ensure the selected folder has sufficient free disk space for the duration of the stream. Segment files accumulate over time and should be cleared after each session.
Advanced Stream Configuration
By default, Tagger uses sensible settings for most use cases. If you need to tune the stream for your hardware or network conditions, expand the Advanced Stream Configuration panel.
Encoding Preset
Controls the trade-off between encoding speed and output quality. Faster presets require less CPU but produce lower-quality video at the same bitrate.
| Preset | Description |
|---|---|
| Ultra Fast | Lowest quality, minimises CPU usage |
| Super Fast | — |
| Very Fast | Recommended for most configurations |
| Faster | — |
| Fast | — |
| Medium | Balanced quality and performance |
| Slow | Best quality, highest CPU usage |
Video Bitrate
Determines the target bitrate for the video stream. Higher bitrates produce sharper images but increase file sizes and network bandwidth requirements.
| Bitrate | Suitable for |
|---|---|
| 1 Mbps | Low-bandwidth environments |
| 2.7 Mbps | Default — suitable for most local networks |
| 5–8 Mbps | High-quality recordings on fast local networks |
Framerate (FPS)
Sets the number of video frames captured per second. Higher framerates produce smoother motion but increase file sizes.
- 15 FPS — Suitable for static or low-movement scenarios.
- 30 FPS — Default. Recommended for most sports.
- 60 FPS — Highest smoothness; requires more processing power and bandwidth.
Resolution
Sets the output resolution of the stream. Lowering the resolution reduces bandwidth and file size without significantly affecting playback smoothness.
| Resolution | Notes |
|---|---|
| Original | Uses the native resolution of the camera |
| 1080p (1920×1080) | Full HD |
| 720p (1280×720) | Recommended for most local network setups |
| 480p / 360p | Low-bandwidth environments |
Segment Duration
Controls how many seconds of video are written to each HLS segment file. Shorter segments reduce stream latency but increase the overhead on the file system and the HLS server.
- Range: 1–10 seconds
- Default: 2 seconds is a good balance between latency and stability.
Keyframe Interval
Sets how often a full keyframe is inserted in the video stream. Lower values improve seeking accuracy but increase file size.
- Range: 15–60 frames
- Recommended: keep at 30 for most sports applications.
Audio Bitrate
Controls the audio quality of the stream. The default of 128 kbps is suitable for standard commentary or ambient sound capture.
Starting the Stream
Once you have selected a camera and an output folder, click Start Live Stream. Tagger will:
- Initialise the camera capture and begin encoding with FFmpeg.
- Wait for the initial HLS segments to be written to disk.
- Start a local HTTP server to serve the stream files.
- Display the Stream URL and begin playback in the preview player.
The stream status alert will change to green when recording is active, confirming that the camera is being captured and segments are being served.
Stream Controls
Pause Recording
Click Pause Recording to halt the camera capture while keeping the HLS server running. The stream URL remains active, allowing existing segments to continue serving for playback. The stream status will show Recording Paused.
This is useful during period breaks.
Resume Recording
Click Resume Recording to restart the camera capture. The stream will continue from the new live segments. The preview player refreshes automatically after a short delay and returns to the live edge.
Stop Stream
Click Stop Stream to fully stop both the camera capture and the HLS server. This clears the stream URL and resets the live capture state.
Refresh
Click Refresh to force the preview player to reload the stream from the current playlist. Use this if the preview stalls or if you have resumed recording after a pause.
Live Edge Mode
The Live button in the top-right corner of the preview player toggles Live Edge Mode. When enabled, Tagger periodically jumps the playback position to the latest available segment, minimising the delay between camera capture and viewing.
- Live Edge Mode on — The button is highlighted in red. Tagger checks every 10 seconds and seeks to the live edge if playback has fallen more than 3 seconds behind.
- Live Edge Mode off — The player follows normal playback. You can scrub and review earlier segments freely.
Live Edge Mode is enabled automatically when the stream starts and when recording resumes after a pause.
Using Live Capture with Tagger Rooms
When using Live Video Capture in conjunction with Tagger Rooms, all participating devices must be running Tagger Desktop. The HLS stream URL is accessible to any device on the same local network, and can be entered as the video source in connected sessions.
Browser-based Tagger sessions cannot access streams served from a local machine. Desktop app access is required for all participants who need to view the live feed.
Troubleshooting
Camera Not Appearing in the List
- Click Refresh Cameras to re-scan connected devices.
- Unplug and reconnect the camera, then refresh again.
- Confirm that the camera is supported and recognised by your operating system.
Camera is In Use Error
Another application is holding the camera device open. Close all applications that may be using the camera, including:
- Video conferencing apps (Zoom, Microsoft Teams, Google Meet, Skype)
- Streaming software (OBS, Streamlabs)
- Browser tabs with active camera permissions
- The Windows Camera app
After closing these applications, click Start Live Stream again.
Stream Stalls or Freezes in the Preview
- Click Refresh to reload the player from the latest playlist.
- If the issue persists, check that the output folder has available disk space.
- Consider reducing the Video Bitrate or Resolution in the Advanced Configuration panel.
High CPU Usage During Streaming
Switch to a faster Encoding Preset (e.g. Very Fast or Super Fast) to reduce the CPU load. This will slightly reduce video quality but improves stability on lower-powered machines.
Post-Session Video Processing
After your session ends, the captured HLS stream can be converted to a single MP4 file for archiving, sharing, or further video analysis.
Use the HLS to MP4 Converter tool to merge the segment files from your output folder into a self-contained MP4. The converted file can then be imported into Tagger as a standard local video source for post-match tagging and review.
See HLS to MP4 Converter for full instructions.
