Why Use The H.265 Video Codec For Surveillance Systems?
If you’re familiar with video codecs and compression for security cameras, you’re familiar with H.264, also known as AVC. H.264 is the most widely-used video codec in CCTV systems (not to mention across the Web), but there is another codec slowly becoming as popular in security systems – H.264’s successor, H.265.
H.265, also known as HEVC for High Efficiency Video Coding, is the latest video compression standard in the MPEG family. Created by the Joint Collaborative Team on Video Coding (JCT-VC), it serves as an upgrade and extension of the H.264/AVC codec, designed to deliver twice the compression performance.
Why Is This Important?
Essentially, H.265 can compress a video file to roughly half the size of an H.264 file (between 40 and 50% smaller) while maintaining the same video quality. If the file size and bitrate are kept the same, the video quality will be much higher. This is especially useful in a world where high-res video (1080P and 4k) is becoming increasingly common while speed and data efficiency remain vital.
H.265 achieves this picture quality using motion compensated prediction, where blocks of pixels are predicted and encoded by referencing pixels in either the same frame or a nearby frame. While H.264 also uses motion compensated prediction, H.265 can use much larger macro blocks – 64 x 64 pixels, as opposed to 16 x 16. This makes H.265 more efficient as it requires less information to encode the same image, and also gives it improved “intra” prediction for each picture, creating a smoother image with less data and better motion region merging.
HVEC also includes Adaptive Motion Vector Prediction, which helps encode motion vectors much more accurately and with less residual error, thanks to 35 intra-picture directions, as opposed to H.264’s 9 intra-picture directions. It also has an improved deblocking filter and Sample Adaptive Offset, which helps improve and reduce artifacts at the block edges.
Like its predecessor H.264, H.265 is capable of supporting resolutions up to 8192×4320 – including 4k UHD – making it applicable to almost any use and more than enough for use with CCTV cameras and surveillance systems.
The Benefits of Using H.265 in CCTV Systems
As H.265 is much more efficient than other codecs, it takes up less bandwidth and much less storage space on a hard drive while maintaining the same video quality. You’ll be able to store much more surveillance video in less space, with clearer images and video at the same time, and can take advantage of cloud recording and storage, eliminating the need for physical hardware. This can translate to huge cost savings, increased efficiency and less maintenance on IP system infrastructure.
Downsides of H.265
H.265 offers much-improved video quality and performance while compressing video, but there are a few drawbacks when adopting it for use in a video surveillance system.
First is the issue of playback compatibility. While almost every native video player supports H.264, very few native players have yet to adopt H.265, making playback difficult on many operating systems. A few select players (such as VLC) do offer H.265 playback, but despite already having been released several years ago, it’s still not a very popular codec.
Most companies that use the H.265 codec in their cameras and systems include proprietary player that is compatible with H.265, allowing you to open and view files using the codec. Moving the video files to another computer or drive without the player, however, can lead to compatibility problems, and many browsers (Chrome, Firefox, etc) do not support the format.
H.265 is also more hardware-intensive, requiring greater processing power to decode and playback video than other codecs. It calls for faster processors and video cards, and IP cameras designed for use with H.265 come with faster, more powerful processors to enable its use.
Are H.265 Cameras Worth It?
Whether an H.265 camera system is right for your business or home depends on a few factors, such as your budget, camera resolution needs and hardware. If you’d like to record and store large amounts of high-quality, high-resolution video while minimizing any loss of quality, they may be worth the investment. But if lower-cost, lower-resolution video will do, and you’d like playback to work on virtually any system or native player, H.264 cameras are probably still the way to go.