I am trying to find the best path for HD live video processing in touch. We recently bought a few Blackmagic Intensity Pro cards, and we discovered that while they work well (even with 2 cards) there is an issue with latency of about 10ms or more. This is exaggerated by the fact that we are using a audio reactive system as an HDMI source, so you can really see the delay. I’ll start out by saying that I know the problem is not Touch …however would it be a.) hardware latency b.) bus latency c.) driver latency d.) direct show latency e.) all of the above
I am sure it is a combo, but is there anything there that can be improved. I am not sure if an SDK is available, but perhaps there is a way to get it to the GPU ram faster and use a shared mem TOP (bypassing microsoft) . The only other system that looks like it has a chance for very low latency is the Nvidia SDI Quadro system, since it drops the incoming stream directly into the GPU ram, but that will require a custom driver to even test it out, plus the whole system is very pricey.
Are there any other HD capture options out there that I should be aware of?
Hey matt, did you mean 100ms? 10ms seems very fast as a full frame at 30fps is 33ms. I’ve heard the blackmagic cards are very good, although we haven’t had the chance to use them yet.
yes, sorry. Actually it was 7-10 frames off at 30 fps, so that would mean 231ms to 330ms. I wonder if the Decklink HD extreme would get better performance. It is pci-e 4 lane vs the intensity’s pci-e 1 lane.
BTW, I am using 1280x720 30fps video from computer via converted DVI to HDMI. Frame rate is perfect, it’s just that delay causing the problem.
MD
I wonder if going straight from a USB3 camera would be better? maybe something like the ones from point grey theimagingsource.com/en_US/ ?
not super cheap but might reduce the latency if the video’s uncompressed. I never had much luck with the directshow drivers for point grey cameras but the cameras are really fantastic.
The Quadro SDI Capture card requires using a custom OpenGL extension, so it won’t work with the existing Video In TOP code. It’s something that I want to do, but the work isn’t scheduled yet. You could probably do it with the CPlusPlus TOP.
…however would it be a.) hardware latency b.) bus latency c.) driver latency d.) direct show latency e.) all of the above