In surveillance applications, losing even a single frame can mean missing crucial details, affecting event reconstruction and security accuracy. However, due to their wireless nature, Wi-Fi cameras are susceptible to network fluctuations, leading to unstable video transmission and even frame loss. To address this issue, Synology has developed Seamless Recording Recovery (SRR) technology, which leverages edge recording to automatically recover lost footage caused by network instability, ensuring the continuity of surveillance video.
Core Mechanisms of Video Transmission and Network Challenges for Wi-Fi Cameras
In surveillance systems, real-time video transmission is critical and relies on multiple protocols and technologies to ensure stable and smooth delivery of video to storage. Synology cameras use RTSP (Real-Time Streaming Protocol) for video streaming, selecting the appropriate transmission protocol based on network conditions to ensure video integrity.
When the camera starts streaming, RTSP establishes a connection with the NAS or client and informs the receiver of the video format and parameters to be transmitted. Video data is encapsulated via RTP (Real-time Transport Protocol) to ensure it is sent in the correct order and plays synchronously. At the transport layer, RTP packets are transmitted using either UDP (User Datagram Protocol) or TCP (Transmission Control Protocol). Video data is transmitted over the network in packets, each consisting of individual frames. Each frame contains critical information, so if a key frame (I-frame) or predicted frame (P-frame) is lost, the video may not display correctly, impacting the integrity of both live video and recorded footage. Synology cameras default to TCP for video transmission, ensuring that even if packets are lost, the system can attempt to retransmit them, maintaining video integrity.
| Feature | TCP | UDP |
|---|---|---|
| Reliability | Reliable, ensures complete data | Unreliable, packets may be lost |
| Order guarantee | Ensures correct order | No order guarantee |
| Packet loss handling | Retransmits lost packets | No retransmission |
Even with TCP transmission, network instability can still cause packet loss, compromising the integrity of recorded footage. The stability of Wi-Fi video transmission is influenced by several factors:
- Electromagnetic interference: Devices such as routers, wireless devices, Bluetooth devices, and walkie-talkies may emit interference, disrupting the stability of Wi-Fi signals.
- Signal attenuation: Wi-Fi signals can weaken when passing through walls, metal structures, or over long distances, increasing the likelihood of dropped frames and delays.
- Bandwidth competition: When multiple devices share the same Wi-Fi bandwidth, congestion in the Wi-Fi frequency band can occur. For example, heavy activities like downloading large files, streaming high-definition videos, or video conferencing can reduce the available bandwidth for surveillance cameras, leading to stuttering or missing frames in video streams.
How Seamless Recording Recovery (SRR) Works
To mitigate video loss caused by network instability, Synology’s SRR technology enables edge recording when stream anomalies are detected. Once the network stabilizes, the missing footage is seamlessly restored to the NAS, ensuring a complete and uninterrupted surveillance record.
1. Real-Time Video Transmission Monitoring
Synology’s technology continuously monitors video stream packet transmission. When the camera detects network instability or packet loss, it logs the loss time and immediately activates the edge recording mechanism. This ensures missing frame data can be recovered afterward, guaranteeing footage integrity. This mechanism effectively addresses common Wi-Fi interference issues, such as frequency congestion, signal attenuation, or brief wireless signal interruptions, ensuring no minor image data loss goes unnoticed. Any missing frame is accurately recorded.
2. Edge Recording and Automatic Recovery
When edge recording is activated, the camera stores lost footage on its microSD card. At Point A, the NAS receives a continuous video stream. When the camera detects network instability at Point B, it automatically triggers edge recording, storing the footage on its microSD card. To ensure a seamless transition, the system pre-records footage slightly before the disruption, marking this as Point B’. Once the network recovers at Point C, the stored footage is transferred back to the NAS, and edge recording stops. This process ensures that even during network disruptions, all critical footage is retained, preventing information loss and maintaining a continuous surveillance record.
3. Seamless Playback Alignment
To maintain a smooth viewing experience, the system aligns recorded and edge-stored footage based on timestamps. When playback reaches a disrupted segment (Point B’), it automatically switches to the corresponding edge-recorded footage, preventing video jumps or desynchronization. This fully automated process requires no manual intervention, ensuring a stable and seamless surveillance experience. The illustration below shows the entire process, demonstrating how footage is seamlessly restored to maintain continuous playback.
Reliable Surveillance, Even in Unstable Networks
Traditional surveillance systems cannot recover lost footage when network instability occurs, leaving critical gaps in security records. Synology’s SRR technology ensures that cameras continue recording during network interruptions and automatically restore missing footage upon recovery. By aligning video timelines, playback remains smooth and uninterrupted. This fully automated solution eliminates the need for manual adjustments, offering reliable and seamless security monitoring at all times.
Experience Enhanced Surveillance with the Synology CC400W Wi-Fi Camera
The CC400W Wi-Fi camera combines flexible installation with built-in AI capabilities for stable recording and effortless setup. It offers both screw-mounted and magnetic base installation options for added versatility. With two-way audio, users can communicate with on-site personnel or issue alerts via DS cam or Surveillance Station.
Discover New Synology Camera | CC400W