H.264 – Bad Internet Video Quality?
Another common opinion based on materials that are often presented incorrectly or out of place. Here, as in the previous case, lack of practice and unwillingness to learn play a very important role. After all, you are just as likely to get poor recording quality due to the curves of the settings, both frame-by-frame and MPEG-like codecs. Many system vendors are squeezing quality to be able to record performance, which leads to this result. Most non-professional consumers also find H.2b4 video on the Internet, where it is highly compressed and intended primarily for a general idea of the comic nature of the scenes or the situation in general.
Here again from the forum: “If, for example, a car is driving in the distance and its wheel falls off in motion, the codec can draw the whole machine from a long-playing keyframe in synthesized frames, along with the wheel that it is no longer there. ” This is possible only in case of a strong underestimation of the bit rate. The Internet is full of compressed entertainment videos, including accidents, and other situations related to video surveillance. It is very strange to consider the quality of this video, obtained, however, by compression in the H.264 format, equal to the quality of the file and draw some conclusions about the quality of the compression format in general. Can’t see the difference in the task of uploading videos to the Internet or recording a high-quality file?
Does H.264 consume more resources?
Many opinions on the subject of H.264 are promoted by individual manufacturers of network video cameras. For example, the article “The hidden cost of N.264”, which exists even in a video version, says that the cost of a solution in N.264 turns out to be significantly higher than that of MPEG or even frame-by-frame codecs. picture. In fact, the resource requirements for decoding video, especially multi-channel and high definition, will be slightly higher than MPEG-4, because all codecs are generally symmetric in terms of resources for encoding and decoding (in the sense, if the codec needs more resources to encode, and this is normal, since the more efficient the codec, the more resources are needed, even for decoding). The question is only on two points.
First, how much more demanding is H.264 on the computer CPU to monitor. Our practice shows that the load on the processor when decoding H.264 depends on the bit rate, however even at the maximum bit rate the download will be comparable to decoding a frame-by-frame JPEG (MJPEG) sequence. The authors of the article “The Hidden Cost of Н.264” focus on the higher cost of client stations and storages (as more and more efficient processors will be required), overshadowing a serious decrease in bandwidth requirements of the net. But even if we’re talking about 30% gain compared to slightly lagging MPEG-4, not to mention MPEG-2 and frame-by-frame codecs as well, isn’t 30% enough? Is it for small “safe cities”, where the rent from providers of data transmission channels costs 70 conventional rubles against 100 (the same 30%), is this a small saving? Or does it not matter that we can transfer 30% more cameras over the existing network?
Second, many “normal” network cameras (I mean more or less professional) are currently capable of transmitting video in two independent streams, with different resolutions, frame rates, and bit rates. And the “normal” software for these cameras also knows how to work with two streams. For multi-screen display, we can choose a low resolution sequence, for full-screen display, the maximum available, the change occurs automatically; the recording in the archive, of course, is done in high resolution. Perhaps you will say that I contradict myself, the second stream in each channel of the network and the saving of at least 30% are incompatible. However, I can assure you that with the correct settings, the second stream will not take up even 5% of the total bandwidth required.
Just go ahead
I’m not trying to act here as an advocate for H.264, I’m just not encouraging the hobbyist, for the fact that PR doesn’t rule reason. Everything must be appropriate for the task. If it is very important to you that your video is of the highest quality, if you want to be sure that it does not lose anything, ZIP is your assistant. Only lossless compression, which none of the codecs used in video surveillance will provide, will satisfy your requirements.
