Merit LILIN talks about H.264 and its ramifications for network cameras and PTZ solutions.
Merit LILIN is currently in the process of adopting the latest video compression technology, H.264/MPEG-4 advanced video codec (AVC), also known as MPEG-4 part 10, main profile (level 3). This compression technique allows for real-time digital video transmission at full D1 resolution via network. With H.264 AVC algorithms, network cameras and PTZ solutions are now equipped with superior video quality, bandwidth efficiency and higher storage utilization for video surveillance applications.
Why H.264?
H.264 AVC delivers better video quality than MPEG-2 or traditional MPEG-4, using the same network but lower bandwidth. Higher compression rates also mean higher storage utilization and lower storage costs for DVR and NVR applications.
The main issue regarding network cameras and video compression is a general lack of standards. A product equipped with M-JPEG or MPEG-4 compatible video codec gives users limited system scalability. On a system level, timestamp information might be added into streaming, and break the compression standard. Incompatibilities with network cameras widely adopted by the market include time-consuming and frequent errors of system integration among products by system solution providers and limited flexibility and scalability in choosing IP products among existing systems by end users.
"To solve this problem, Merit LILIN is currently unifying network cameras and DVRs into a single system platform," said Tan-Pin Hsu, VP of Merit LILIN.
Verification and Standards
Merit LILN's H.264 AVC is analyzed and verified by a third-party H.264 streaming analyzer. Verification can also be done through H.264 software players such as KMPlayer and VLC Player on Microsoft Windows and/ or Linux platforms. For mobile devices, CorePlayer is used for verifying H.264 AVC streaming.
Timestamps are crucial information for video surveillance applications and for evidential purposes. This information can be later interpreted by software or hardware NVRs for end users. Merit LILIN utilizes decode time stamp (DTS) and presentation time stamp (PTS) for time information without compromising the standard of H.264 AVC streaming.
Merit LILIN's latest IP or DVR products adopt HTTP and UDP unicast/multicast protocols for transmitting H.264 AVC streaming. For Internet environments, the advantages of adopting HTTP ServerPush transmission technology include a more efficient protocol that reduces the device's CPU loading, eliminates RTSP port settings typically required by end users, is backward compatible with Merit LILIN's JPEG network camera platform and has a simple protocol for testing and verifying streaming by system developers.
Low-Latency PTZ Applications
For low-bandwidth networks, users currently receive live video footage roughly five seconds after images have been captured by PTZ cameras. Low-latency designs for PTZ products using H.264 AVC can be considered for both Internet and LAN environments, increasing the speed and efficiency of fast PTZ positioning to cope with low-bandwidth users.
HTTP ServerPush also reduces computational complexities for sending and receiving video streams. Merit LILIN's network camera latency can be minimized to within 300 microseconds at a bit rate of 2Mbps in full D1 via the TCP protocol. Thus, for PTZ applications, end users will receive little video delay, said Hsu.
Future Development
For system integrators, Merit LILIN's H.264 AVC SDK allows system developers to integrate H.264 AVC into their existing software systems. Future H.264 DVR development will follow this trend and provide a single SDK for both network cameras and DVRs, helping reduce tremendous development time for software developers.
Merit LILIN's H.264 AVC codec SoC integrates advanced H.264 algorithms, including inter-frame prediction, variable block-size motion compensation, main profile (I-, B-, P-frames) and entropy coding. These effectively improve video quality at a high compression rate.
LILIN's latest H.264/MPEG-4 AVC SoC provides better video quality and low video latency for network transmission. Real-time display and full D1 video resolution are increasingly in demand by the global video surveillance market, said Hsu. With this technology, LILIN will focus on delivering a series of H.264 AVC-based network cameras. Its development focus will gradually shift to H.264 AVC network codecs and network video solutions to cater to today's rigorous demands.