mrB 0 Posted January 12, 2004 Hi everyone, I’m looking for some advice and suggestions on building a portable cctv system to support a research project that I am conducting. The project is concerned with image processing of cctv video images in indoor environments. I don’t know an awful lot about the hardware side of systems, so I am hoping someone will be able to point me in the right direction. I want a build a portable system supporting 2 colour cameras (probably low-light capable) which can record video images at the highest possible resolution. I’ve seen cameras advertised which can capture at 752x582. This is ok, but I am wondering if it is possible to capture at high resolutions? Frame rate is not so important: 5 - 10 frames per second would be ok. The captured video ultimately needs to be transferred to PC, so I am thinking of using a DVR capture card to record straight onto a PC. I haven’t seen any cards advertised that support 752x582 though. Does anyone know of any? I also want maximum flexibility in terms of compression encoding, as final image quality is important. I notice that DVR cards often have automatic recording control based on motion detection. I would also like to be able to configure this and have the option of using it or not. Finally, I would like to be able to record for as long as possible without changing media – which is why I am thinking of using PC + DVR Card + Big Hard disk. If anyone has any suggestions, advice or comments I would be very grateful. Share this post Link to post Share on other sites
cctv_down_under 0 Posted January 13, 2004 Most PC based recorders wont go much past 640x480 resolution (PAL) there are speed and interlacing issues once you go past that and infact when most manufactorers mention speeds they are stating speeds @ 320x240 (PAL) only and when not using Hyperthreading CPU's and all cameras are recording at once you will find that 90% will be slower at the larger resolution. However there are some exceptions to that rule, for example the http://www.dallmeier-electronic.com/ actually capture at a large 720x576 resolution and are able to do this due to the Linux operating system. Standalone devices are more likely to capture full sized recordings as that is what they are designed to do. A standalone is a DVR that is not a PC and it is made just for that purpose, they lack a lot of features but some do have motion detection options that can be turned on or off at any time (99% of all PC ones do this as standard). Standalones are more stable and easy to move around. It is not the Camera that does your capturing it is the DVR card itself. Because a PC can crunch the video (compress) better than most standalone box's you should get better options for storage with a PC based system, also a PC mainboard will support larger drives later with a BIOS upgrade, but a Standalone box may not. I think most DVR products crop the images to avoid interlacing and storage issues, so if you find one that does a larger res please let us know on here. Share this post Link to post Share on other sites
mrB 0 Posted January 13, 2004 Thanks for your advice. Yes, stability is always an issue, so I now thinking of using a stand alone DVR recorder rather than a PC base system... Share this post Link to post Share on other sites
cctv_down_under 0 Posted January 14, 2004 If set up correctly a PC based system is about 88% as stable as a standalone. Share this post Link to post Share on other sites
AVCONSULTING 0 Posted January 15, 2004 A portable system should use an embedded DVR for ruggedness and reliability. It will get knocked around a lot. In fact a mobile DVR would probably be the best choice. Share this post Link to post Share on other sites
