H.265 (High Efficiency Video Coding, HEVC) is the successor of the de-facto standard for video compression on the internet: H.264/MPEG-4 AVC (Advanced Video Coding). The ITU members agreed on this new standard at January the 25th, 2013.
The ITU states that H.265 only needs about half the bit rate of its predecessor H.264 for the same video quality. Because 80 per cent of all web video now is coded with H.264 and, by some estimates, half of internet bandwidth use is caused by video, H.265 can drastically unburden global networks. Thus High Efficiency Video Coding will enable the next wave of innovation, from streaming HD video to mobile devices to Ultra HD TV.
HEVC is targeted at next generation Ultra HD television and supports resolutions from 320×240 to 8,192×4,320 (4320p or 8K). Besides the high resolutions it is also allows a better image quality by reducing noise levels and increasing color gamut and dynamic range.
The efficiency of video coding tells about the ability to minimize the necessary bit rate for a given level of video quality. The more efficient a codec is, the lesser file size of a video will be. According to a comparison to its predecessor, H.265 out-performs H.264 in average by 39% in scenarios like video broadcast and by 44% for scenarios, where a low delay is vital (e.g. video calling).