Table of Contents
Automatic Configuration
When a camera is added or reconnects, TetherBox automatically configures its settings for optimal performance, eliminating the need for manual setup. This page covers exactly what gets changed and on which cameras.
If you do not want TetherBox to change your camera settings, you can disable this per camera. See Disabling Automatic Configuration.
Stream Settings
TetherBox configures both the recording (primary) and analytics (secondary) streams:
| Setting | Recording Stream | Analytics Stream |
|---|---|---|
| Codec | H.264 | H.264 |
| Resolution | Highest 16:9 available | 720p (or camera's maximum if lower) |
| Framerate | Maximum supported at chosen resolution | 6 fps |
| Bitrate | Auto, based on resolution (see table) | Auto, based on resolution |
| Bitrate control | VBR (Variable Bit Rate) | VBR (Variable Bit Rate) |
| Profile | High | Baseline |
| GOP (keyframe interval) | Equal to framerate (1 keyframe/second) | 6 frames (1 keyframe/second) |
Recording stream: The framerate is set to the maximum the camera supports at the selected resolution, typically 25 fps at 1080p or 20 fps at 4K. The GOP (keyframe interval) matches the framerate, giving one keyframe per second for efficient seeking and smooth cloud playback.
Analytics stream: Capped at 720p, Baseline profile, 6 fps. The TetherBox decodes this stream locally for motion detection. Higher resolutions and framerates provide no detection benefit while significantly increasing CPU load, limiting the number of cameras the TetherBox can handle.
Tip: When a cloud backup package is assigned to a camera, the recording stream resolution is automatically capped to match the package tier (e.g. a 2MP package caps recording at 1080p). This ensures cloud backup bandwidth and storage costs stay within the selected plan. The analytics stream remains capped at 720p regardless of cloud package.
H.264 is the default codec for compatibility reasons. See H.264 vs H.265 if you want to use H.265.
Automatic Bitrate Selection
| Resolution | Bitrate |
|---|---|
| D1 (704×480) or less | 768 kbps |
| 720p (1280×720) | 1024 kbps |
| 1080p (1920×1080) | 2048 kbps |
| 5MP (2592×1728) | 3072 kbps |
| 4K (3840×2160) and above | 4096 kbps |
These bitrates balance recording retention, cloud backup costs, mobile/browser streaming reliability, and image quality. With VBR enabled, actual average bitrates are often well below the configured peak. The encoder uses fewer bits for static backgrounds and more for moving subjects.
These defaults suit most surveillance installations. If you find that specific cameras need higher bitrates, for example in scenes with constant movement across most of the frame, you can enable Disable Defaults on those cameras and configure streams manually. See Disabling Automatic Configuration.
Tip: Most stream settings can be changed directly from the camera's API tab in TetherX. For settings not available there, use Tunnelling to access the camera's web interface remotely.
Time Synchronisation
Accurate timestamps are critical for evidence integrity. TetherBox sets the camera's NTP server to the TetherBox IP address so the camera continuously synchronises its clock. If NTP configuration fails, TetherBox falls back to setting the camera's clock directly.
The TetherBox itself synchronises with internet NTP servers, so cameras receive accurate time without needing direct internet access. See TetherBox Time Synchronisation for more details.
Motion Detection and Smart Analytics
On supported cameras, TetherBox enables the camera's built-in motion detection for intelligent recording and notifications.
On cameras with Video Content Analysis (VCA) support, TetherBox enables smart analytics mode. This activates built-in detections such as people and face detection that work without any additional configuration. Features like line crossing and intrusion detection require manual setup as TetherBox cannot know where to draw the boundaries for your scene. You can configure these via tunnelling to the camera's web interface.
On cameras with built-in license plate recognition (LPR/ANPR), TetherBox detects the capability and configures the appropriate VCA mode to keep it operational.
Supported Cameras
Any ONVIF-compliant camera will receive automatic stream and NTP configuration. TetherBox also implements native APIs for manufacturers like Hikvision and Dahua to support brand-specific features such as smart analytics, license plate recognition, and advanced event handling, but typically uses ONVIF for stream configuration as it provides a consistent experience across all brands.
Here are some examples of common manufacturers and the level of automatic configuration they receive:
| Camera | Streams | NTP | Motion | Smart VCA | LPR |
|---|---|---|---|---|---|
| Hikvision | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dahua | ✓ | ✓ | - | - | - |
| Uniview | ✓ | ✓ | - | - | - |
| Axis | ✓ | ✓ | - | - | - |
| Hanwha | ✓ | ✓ | - | - | - |
| Merit-Lilin | ✓ | ✓ | - | - | - |
| Homaxi | ✓ | ✓ | - | - | - |
This is not an exhaustive list. See Supported Devices and Integrations for a full list of compatible cameras and devices.
Disabling Automatic Configuration
If you prefer manual control over camera settings:
TetherBox will stop modifying that camera's settings. See Manual Camera Configuration for recommended manual settings.
Configuration Suggestions
When automatic configuration isn't available or a camera's settings don't match recommended values, TetherBox displays suggestions on the camera index (warning icon) and camera page (badge) explaining what needs adjustment and why.
H.264 vs H.265
TetherBox defaults to H.264 for maximum compatibility. Many cameras produce non-compliant H.265 streams that cause playback failures, and H.265 requires specific hardware support:
- Safari (iOS/macOS) - Native support
- Chrome/Edge/Firefox - Requires hardware decoding (Intel HD4400+, NVIDIA GT635+, AMD RX460+, Apple M1+)
- Android - Many devices lack H.265 hardware decoding entirely
Warning: Even compatible devices may struggle with high-resolution H.265 using High profile. If playback stutters, try Main profile or switch to H.264.
Using H.265 for Recording
H.265 offers approximately 50% bandwidth savings at equivalent quality. To use it:
- Enable Disable Defaults on the camera (above)
- Configure H.265 from the camera's API tab in TetherX, or via Tunnelling if the codec option is not available there
- Test playback on all devices before rolling out
Tip: While the recording stream can use whichever codec your camera and viewing devices support, the analytics stream should always remain H.264 Baseline. The TetherBox decodes this stream locally for motion detection, and there is no quality advantage to using a higher codec or profile for analytics. H.265 on the analytics stream will significantly increase CPU load without any detection benefit, reducing the number of cameras the TetherBox can handle.
Troubleshooting
Configuration not applied:
- Verify camera has API access (ONVIF enabled or native API supported)
- Check camera credentials are correct
- Ensure camera firmware is up to date
Settings reverting:
- Some cameras reset settings after reboot. This is a camera firmware issue
- Check if camera has "restore defaults on reboot" enabled
Motion detection not working:
- Some cameras don't support remote motion detection configuration
- Configure manually in camera's web interface