Cineastas have breathtaking experiences. The screens are getting bigger and bigger, the screen is getting bigger and more and more natural. At the very least, this is the declared goal.
A long way
But such pictures need food. Data feed that can be loosely in the range above 25 megabits per second. At least according to today's H.264 bill. And that is not acceptable in terms of costs as well as transmission capacities in the TV area. For comparison: For high-quality HDTV transmissions are currently investing 12 megabits per second data rate, good Blu-rays come on average to 25.
Claim and reality
Therefore, the technology tries to adapt to the home cinema needs. This innovation is called High Efficiency Video Coding (HEVC or H.265) - the direct successor to the proven H.264 codec for HDTV.
The HEVC application fields
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HEVC is still in the development stage
As with H.264, also called Advanced Video Coding (AVC) is a data reduction method. The goal is to transmit as little data as possible for a complete TV picture. AVC has enabled HDTV due to its compression capabilities. HEVC is supposed to have another one on it and need 40 to 50 percent less data than its predecessor.
At the beginning of June the codec was now adopted as a standard. The journey from the idea to the application of such a compression process is long.
AVC history
The history of HEVC began in 2004, when other possibilities of data compression were considered. However, with the adoption of the standard, the procedure was far from being marketable. The codec describes, in a simplified way, what belongs to it and how it deals with it. The way how this data is handled in practice is then the job of suitable software, which has yet to be developed.
The companies that want to sell their solutions in competition with each other to TV program or Internet services providers. Program development and contact are currently taking place.
Just how challenging it is to develop such software is illustrated by Rainer Schäfer, Head of Television Business at the Institute of Rundfunkunktechnik (IRT). He talks out of the sewing box that a software created at the end of the H.265 creation phase needed immense time to create the data required by the codec from real images: "The program needed almost a full day for about ten seconds of motion pictures." In practice this is unacceptable.
Companies specializing in "encoding" can dramatically improve the results. Developer Rovi is here. Thomas Kramer is the product manager responsible for HEVC. His department has been busy for about 18 months. In the race for the best values, Rovi is about 15 to 20 percent reduction of data compared to AVC - still far from the desired 50 percent.
It is quite normal that the first encoder versions are not as powerful, "explains the expert." Gradually the know-how grows and one approaches the goals. "His estimate: In three to four years, Between 30 and 40 percent data reduction against AVC.
Schäfer reports the same about the HDTV introduction. That was at that time by Abo-TV provider premiere coined, which stood under money and time pressure. The first AVC encoder produced hardly a lot of data than the MPEG-2 predecessors. It was only eight months later that you could take advantage of the new codecs.
Ultra HD and DVB-T2
Even today the performance of the long established encoders is still improving. And this on uneven ground: It is significant, with which devices and distribution paths a codec is used. Rovi is primarily active in the Internet environment, where the various types of computers, tablets, smartphones, smart TVs and smart receivers. Depending on the computing performance of these devices, the top-level models might already be expected to decrypt HEVC data, explained Rovi product manager Thomas Kramer. They would be given an appropriate program to enable them to decode the data.
However, such "software decoders" are not adapted to the specific device. Software and hardware are independent of each other and always adapt to each other.
This also applies to the front side. If a provider of IPTV or Video on Demand with the HEVC codec to stream his offer, he installs the appropriate "software encoder". The device and the program are also found here afterwards.
Practice: What makes H.265 better
This is different in the context of television broadcasting. Here device and software merge and are available as a unit. Therefore, one speaks on the front side of a "hardware encoder", which the respective TV transmitter integrates into the system.
In the case of the TV customer, a set-top box is also provided, which is also a unit of software and a suitable high-performance hardware. The Blu-ray camp is still unclear to what extent the codec on disc will find its place. The official statement is that you are working on a new standard, which is to be finished by 2017. Whether H.265 is part of it, still seems to be open.
In the mobile phone environment, HEVC could also play a role as soon as the transmission of moving pictures. IPTV would then be conceivable. However, there are no announcements.
In fact, not even the standard is completely finished. The long, technical names for a codec show its version. Over time, the appendices are changing, signaling that further deeper standardization steps have been taken. Thus, IRT-Schäfer knows that the HEVC codec covers all requirements for the TV and home cinema area, but can not yet be used in production at the film and TV studios. Here, for example, the integration of the color depth with which one works in this area is missing. Such codec shares will be integrated over the coming months.
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Good prospects seem to exist with regard to TV use. The hardware encoder prototype of a manufacturer, which produces only 40 percent of the AVC codec in a practical time, ran on the IRT. "We were quite surprised," Schäfer admits. So you can be optimistic. The product is not yet ready.
The programmers like Rovi are still in the development stage. So far, there are only test runs, explains Thomas Kramer. Nevertheless, the manufacturer wants to be the first in the Internet area with a solution. At the end of this year, the first HEVC concept for sender and receiver is to be offered as a software solution.
At this point, it is likely that HEVC will not only require comprehensive changes to the content providers.
Consumers are also looking for changes. While these are more likely to take place automatically in mobile devices and computers due to the shorter product cycles, the TV viewers have a new acquisition. Neither separate set-top boxes nor receivers integrated in televisions have, according to current estimates, sufficient computing power for HEVC.
However, the bitter pill is somewhat sweetened. Together with HEVC, the companies mention the fourfold Full HD image point number Ultra High Definition (4K) in one breath. The HEVC codec is intended to provide not only for lower data rates, but at the same time enable higher-resolution images. And for this technology, new TVs and set-top boxes are needed anyway.
HEVC could also be the occasion to introduce DVB-T2 as transmission technology already in the United States, in itself, already overdue transmission technology for the Antennenfernsehen. Then there would be no more obstacle from the jump from standard to at least HD resolution.
It seems certain that HEVC is entering the Internet at the end of the year. For TV use, Rainer Schäfer points out that MPEG-2 and -4 were the first TV receivers and the television broadcasting began approximately two years after codec standardization. This would be transferred to HEVC to the Sky plans to start with the UHD broadcast already in 2017.
From 1995: first preparatory work at universities and companies from the completion of MPEG-2, 1998: Start of the standardization work 2001: Beginning of the collaboration of MPEG and ITU at H.264, 2004: Extensions for high quality (Fidelity Range Extensions); October 2005: Implementation of first hardware encoders for TV stations, no data protection against MPEG-2, October 2005: Parallel operation of SD and HD with ProSiebenSat.1 (Blu-ray), the first Blu-ray player to arrive in December 2006, will be released in December 2006 To the market, July 2008: ARTE HD starts 2008: Implementation of a hardware encoder at the public-law broadcasting stations 2008: First test broadcast on Einsfestival HD, starting October 2009: Single TV cable networks start with the feeding of the HD channels; February 2010: Data compression is about 50 percent higher compared to MPEG-2, May 2011: HD is over IPTV (Telekom Entertain), Today's status: Data compression is on the stand From 2011
