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Comparing H.264 and VP8 for Video Conferencing

Leading experts of SPIRIT, the world leader in voice and video over IP networks, are confident that the H.264 codec remains the ideal choice when encoding a video stream in video conferencing solutions.

Despite the fact that the VP8 codec showed good results in coding quality of the recorded videos, it should be noted that the transmission of streaming video in real time is the subject of separate studies, and such studies were carried out at SPIRIT.

According to their results, we can say that the VP8 codec is generally good, but so far only as a free add-on. For high-quality video communications, and especially for video conferencing, its functionality is not enough. VP8 will not be able to cope with real-time video encoding of 30FPS in HD quality even on a computer equipped with an Intel Core2Duo 3 GHz processor. In turn, the implementation of the H.264 codec by SPIRIT is faster than VP8 in performance by 5 times and without problems encodes the picture in HD quality on such a computer.
vp8 vs h264
What is more, SPIRIT is not the only one who has proven in practice a significant VP8 lag in speed. In July 2010, comparative tests of VP8 and H.264 codecs were carried out at the Computer Graphics and Multimedia Laboratory at Moscow State University, which showed that VP8 is, on average , 5-25 times slower than H.264 in coding mode.
Even experts from Google, the developer of the VP8 codec, have recognized that the codec is not fast enough, since the work on optimizing it is at the very beginning:

[Q] Encoding video in WebM format [container containing VP8 codec] seems really slow. How do you solve this problem?

[] We just started optimizing the VP8 codec and believe that we can soon achieve a significant increase in the speed of its work.

Source: http://www.webmproject.org/about/faq/

It is also necessary to take into account that the final quality of the video that the user sees depends only partially on the codec. The fact is that in online communications, video is not shown to the user “as is” (as it was encoded), but is first transmitted over IP networks, where there are always losses, delays and errors in the delivery of data packets. Only an effective fight against their consequences ensures the good quality of the video that end users see. SPIRIT has developed and delivers, in conjunction with a codec, special algorithms to combat losses and delays in the network, which allows for high quality video even after its transmission over packet networks, that is, in real online video conferences. This is especially important in the conditions of Russian networks, where the quality of Internet access sometimes leaves much to be desired.

In addition, unlike VP8, the H.264 SVC codec as part of a complex software solution can quickly adapt to the channel, communication. H.264 SVC is capable of changing the bitrate without transcoding on the fly, reducing or increasing it, as well as varying parameters such as the number of frames transmitted per second (fps), video resolution and coding quality in real time. This allows you to "smooth" the video on the receiving side. When using H.264 SVC coding technology, the user almost does not notice the artifacts in the video stream. The video does not freeze, does not fall apart and always remains dynamic.

SPIRIT technologies provide high quality of communication even in difficult network conditions, which allows you to instantly adapt to the channel and deliver high-quality audio and video to each user. These technologies were embodied, in particular, in VideoMost online video conferencing solution.

From our point of view, the desire to launch a product based on third-party technology in many ways contributes to saving on development and rapid advancement on the wave of success of a new solution, but at the same time does not benefit the independent progressive development of the company in its industry.

The company Video Bridge primarily values ​​the stability and quality of its systems for video conferencing, rather than trying to use fashionable unverified news. Therefore, VideoMost is built on the basis of SPIRIT software solutions, appreciated by such companies as Adobe, Microsoft, Oracle, Polycom, Skype, as well as 250 other world leaders in the field of software development and communications equipment that have successfully implemented SPIRIT software in their products and Services.

This is the only cross post from our official blog http://blog.videomost.com/

Source: https://habr.com/ru/post/101472/

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