On Mon, Dec 13, 2004 at 11:06:46AM +0100, Dik Takken wrote: > > So, I'm looking for a decent hardware MJPEG capture card that is > currently available in computer stores.
I'm not so sure that such exists today. Unless you consider Ebay to be a "computer store" in which case MJPEG capture cards are (intermittently) available in the "store". Keep in mind as well that for MJPEG, if you crank the quality of the recording up quite high, you'll also need a speedy hard drive to swallow the data as fast as the card will output it. The formulas I used to estimate space consumption from my DC10+'s were: if 320x480 frame then size_per_hour = 20.0 GB/hr * quality_factor/100 if 640x480 frame then size_per_hour = 40.0 GB/hr * quality_factor/100 Those two formulas were pretty accurate in estimating the amount of data that any particular capture session would produce. "quality_factor" is the -q option to lavrec. There's no entry for 704x480 or 720x480 simply because a DC10+ can't capture at more than 640x480. > If MJPEG is still the best choice today, that is. I have seen new > (external) capture devices that can convert analog video directly > to DV and stream it directly to your harddisk. How good/bad is the > quality of these devices? You'll have to discuss that with our resident DV advocate, Steven Schultz. The quality is quite excellent from what is reported. > Say I want to process the video after capturing and re-encode to > MPEG2, does DV offer sufficient image quality to do this or is an > MJPEG capture card a better choice? I think Steven would say that DV would offer better quality than the MJPEG solution. DV is also a newer compression algorithm and as such it had the opportunity to learn from MJPEG and correct some edge conditions that reduce MJPEG's potential quality. > Do external capture devices have a big advantage compared to > internal capture cards? No need to open the PC to install? :) Easy to move from PC to PC? :) Seriously though, given the same quality hardware, and sufficient bandwidth on the "link", it should make no difference quality wise if the card is internal or external. However, you've also not said what you believe your intended use may be for this setup? Given what you feel is your intended use, you might also consider one of the hardware mpeg2 compression boards instead of a MJPEG/DV solution. I can attest that the Hauppage WinTV PVR250 card's will generate a simply beautiful picture from analog cable TV, and there's no fuss/muss with needing to re-encode anything. ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
