Low latency viewer is a simple player for H.264 streams from an IP camera. It achieves good latency even though it doesn't make use of hardware acceleration for decoding. Of course the camera itself is an important factor but generally speaking 120 - 150ms end-to-end latency should be possible for a 1080p stream on average computer hardware. Tweaking things a bit, the best result obtained was ~70 ms end-to-end.
It's a test tool, not suited for movies (no audio). There is a binary version for Windows and Linux. These are statically linked and free of dependencies, so zero-install. For Linux this may not be 100% true, depending on your distro some installation of extra components may be required
Features
- H.264 (base/main/high profile)
- HTTP-JPEG
- RTSP with unicast and multicast UDP-RTP, TCP-over-RTSP transports
- Basic and Digest Authentication
- Commandline interface and GUI
- Joystick PTZ-control for Axis cameras (0.0.3)
- Single self-contained executable, no install
- Client-side metadata overlay of some camera analytics
- Some error condition overlays explained on the documentation page
What makes it low latency?
- It shares the load (receive& reconstruct, decode, scale, render) over multiple threads
- When it runs late:
- Skips remaining P-frames in the queue as soon as an I-frame arrives
- Drops frames before scale/render early to ease the load but continues to decode to keep consistent decoder state
- Explicitly requests I-frames in case of decode error, thus allowing very long GOPs, which improves networkload and with that jitter/latency
- By default it does not attempt to correct jitter
What makes it a test tool?
- Lack of playback features :)
- It highlights errors. Jitter will be visible, overlays are shown for packetloss, frame drop or running late.
Compared to VLC
VLC is complete media application which can play-, record-, convert- and stream almost every media format. Llv just plays a h.264 videostream in a simple way. It does add some IP camera-, mostly Axis-, specific tricks. The main differentiator is low latency, which is something VLC is not. But VLC is a must-have companion program. Where Llv is not enough and you need to use VLC, here is a page with tips.