pingsquare 0 Posted May 19, 2005 Hi, i've been trying to know finding out about these h.264 compression board these few days. I have a few questions... 1. Boards with h.264 compression(hikvision), do they have better performance then the current that we have like Kodicom and Geovision in terms of recording and network viewing? 2. what does cif card means? half d-1 and full d-1? will appreciate your enlightenment... Share this post Link to post Share on other sites
scottj 0 Posted May 19, 2005 ABout the boards compression...I doubt you would even notice a quality difference unless you use top of the line cameras. The compression algorithm in this case will mostly affect the storage capacity as the primary feature. In response to question number 2....... An explanation in broad terms and not getting to technical CIF means Common Image Format. If we look at the best resolution a CIF can produce you start to see the loss of resolution proportionately. An example of resolution in the various formats is as follows: D1 Resolution H480 X V330, CIF 4 Resolution 480H X V330, 2 CIF Resolution 480H X V162, CIF Resolution H240 X V162, QCIF Resolution H20 X V80. Please note the horizontal resolution remains high but the vertical resolution decreases by a factor of two (2). The D1 format is presently the best you can achieve. HDTV technology will challenge this quality in the near future. The total number of pixels drops dramatically and effects computer power, memory and bandwidth to compress, store and transmit. Be careful not to assume the image will be two, three or four times better or worse. The human eye will notice the difference but technically it is not a cut and dry equation. If you compare the Digital Recorder specification and then compare them to the CCD camera specification you will notice a 500-pixel camera are specified at about 330 lines of horizontal resolution and the 720 pixel-camera produces approximately 480 of horizontal resolution. The vertical resolution on all cameras is the same since they all have 484 active raster lines in NTSC format, which yields approximately 320 lines vertically. scottj Share this post Link to post Share on other sites
cctvexpert 0 Posted June 19, 2005 I strongly believe he is wrong about the comparison. First of all H264 attributes are well documented in numerous industry whitepapers. First of all the video quality is superior in every regard, especially when dealing with fast motion where with traditional mpeg4 you will get artifacts and mosaic. Next this is all hardware compression and with hardware compression you can run the limit of the pc as far as the pci or pci-x limitations and the cpu usage will be nil. With respect to audio it is truly a perfectly sync'd audio because it runs the audio through the DSP. All the core functions are run on the DSP. Anyone in the video codec side of the business will tell you there is no comparison and is the reason that development of the H264 (MPEG4 Part 10) standard was adopted by both ISO and ITU and the other standards were dropped. Further the codec has error correcting protocol and in regard to I-frame/P-frame issues is incredibly efficient. In my opinion, there is no comparison as Geo or the others are not in the same league. The downside is you need a powerful video card to run it properly. Therefore, computers that are just a couple of years old will have trouble running the remote client. Share this post Link to post Share on other sites
Thomas 0 Posted June 20, 2005 H.264 does edge out MPEG-4 at higher resolutions but not radically so. At lower resolutions it's pretty much a dead heat. It's nice but it does have some issues. H.264 codecs have been noted to not play nicely with some older MPEG-4 codecs. Share this post Link to post Share on other sites
