The advantage of temporal ( Wireless GPS Tracking Device ) compression is that audio is almost always part of such a scheme. Temporal compressions makes better compression of the video sequence as it uses motion prediction so that object motion looks smoother when playing back. Because of this fact, video compressions are not used to multiplex cameras into one recording system. Rather, if a DVR that uses temporal compression has multiple camera inputs, they are usually independent steamings recorded on hard drives. Another important feature associated with temporal compression is the time delay (latency) which happens on video compressions such as MPEG-1 and MPEG-2. This is a result of how the video compression is designed to work, where video signal redundancy is reduced by comparing past and future reference points, a technique that requires some buffering. More susceptible to this effect is MPEG-2, where high video quality is achieved with higher bit rates, typically over 4 Mb/s, and this may produce a latency from around half a second up to a second.
The temporal (video) compressions that use lower bit rates and are designed for video conferencing (thus a need for bidirectional video streaming), such as H.263 and MPEG-4, have much lower lag, though lower picture quality too. rior to any digital processing, the first stage is analog to digital conversion (A/D). Such a circuit could exist inside an IP camera, or a Navigation Rear View Mirror . This is a stage where the analog signal is sampled and quantized in order to be converted to digital format. It should be noted that this is the ITU-601 digitization recommendation, and as we said earlier, it is in use in the majority of digitization products in the CCTV. There is no advantage of using cameras with much higher resolution than 450 TVL when the same is to be recorded on ITU-601 compliant recorders. This is the same argument as when we had high-resolution cameras (460 TVL for example) being recorded on VHS VCRs (which are limited to 240 TVL by the low-pass filter design). The difference here is not so dramatic, as some CCTV manufacturers lately have come up with color cameras offering 520 TVL, for example.
Practically, this means you cannot see any difference between a 460 TVL or 480 TVL or even 520 TVL camera, when these are to be recorded even on the best quality ITU-601 compliant DVR. More attention should be directed to choosing a camera with a better signal/noise ratio, less smear or better dynamic range than to slight differences in horizontal resolution that nobody can see. If a system is designed and used for just live monitoring, on high-quality Vehicle GPS Locator with better than 500 TVL resolution, such a small difference in resolution might be advantageous, but unless Y/C connection is made to the monitors instead of composite video (and this is really very rare in CCTV), not much difference can be seen even then. No one can predict what the future will bring, and I am confident that sooner or later we will have some version of high-definition CCTV cameras, which will then be accompanied with the appropriate high-definition digitization recommendation.
More information at http://www.jimilab.com/ .