I would like to buy a SDI PCI card but I don’t khnow if it work in real time without slow down my system. Normaly, the decklink ones works without compression. Does it means that the pixels go directly in my graphic card or is there any process.
We have not tested the decklink card yet.
alas, we have some experiences with the Immersive Holo3d, which is a very flexible card which has SDI, YUV, RGB, SVideo and Composite inputs, and provides hardware deinterlacing. It showed a very good performance with no visible performance difference between SDI and Component signals. We had solid 50fps at full frame sizes on a 2.8GHz machine with a Matrox Parhelia. Afaik the Holo3d is discontinued now and the drivers never got completely debugged - so if you plan on using the card be prepared for some chroma delay artifacts and spurious white pixels in the image.
vvvv utilizes DirectShow and VMR9 - so the pixels should go as direct as possible from the capture card to your textures. as long as you dont include any freeframe nodes, the actual video data stays in kernel space and vvvv doesnt touch it.
Seinterlacing is another can of worms. Best option is having the input card doing the deinterlacing (like the Holo3d). vvvv can do deinterlacing under certain circumstances, but joreg needs to elaborate more on the exact circumstances.
writing a pixel shader for adaptive deinterlacing is one of my pet research projects, but i never really started to implement that. tell us your results…
depends on the graphic cards drivers. if it can output in a yuv format (which i guess all of the drivers can) the pixels will go directly to the graphics cards. rgb-formats will always go through the cpu.
since an sdi-signals resolution is standard pal (or ntsc) there is hardly any lag. at first. but beware! who will do the deinterlacing for you? ( the deinterlacing videotexture is rather buggy still. hope to have a better version in the next release). i only know one card that does it in hardware for you which i would not really recommend because it has bad chroma delay: [holopro3d](](holopro3d]()http://www.digitalconnection.com/Products/Video/h3dgraph2.asp)
software deinterlacing will take your pixels through the cpu again. as long as you don’t need lipsync video the delay of 3-4 frames should however not be noticable.