How to avoid dropped frames at VideoIn?

Hello,

I am using Decklink Extreme 3D. At this card I have a VideoSignal coming from HyperDeck Shuttle in HD 1080i 50hz. When I play out something and take a look in Media Express whats coming up, i can see a lot of dropped frames. I have multiply this signal by using a Signal-Distributor to see the Original Video on a extra monitor. The signal is stabil, but each minute the signal gets lost in Media Express. When i capture this signal the process will be aborted cause dropped frames.

Have you any idea, what the reason could be for dropped frames???

1st of all, i will update my Driver from 8.0 -> 9.0.

Thanks Thomas

[Joshua Helling]

Dropped frames are almost always caused by insufficient drive speed.

In your case you are playing back from a drive and capturing to a drive, so you'll need to check both.

When you playback watch the front of the Hyperdeck shuttle. If you see a blinking red light, that means the drive on the Hyperdeck is dropping frames. If this is not the case, then your hyperdeck is doing what it is supposed to do.

So for dropping frames on capture there are a few things to consider. Codec is the largest consideration. If you are using Uncompressed, your hard drive will need to sustain 156.5 MB/second of data throughput (minimum). You can check this by running the disk speed test utility that we provide with our Desktop Video Products. Cross reference the matrix and it will clearly tell you if you have enough drive throughput.

If it turns out you do not have enough throughput there are a couple of different ways to handle it. First you could use a compressed codec. That requires much less. Or you can install a hard drive array which should increase the throughput available to that drive.

So those are some low-hanging fruits to check.

If you're seeing dropped frames in preview, it's possible you installed the Decklink in a 1x slot, or the slot is set to 1x speed.

Hi,

@Joshua

-> Thanks for your reply. I was using the Hyperdeck only to get a signal into the Decklink Extreme. There is nothing flickering in red at the front of Hyperdeck. The Signal for sure is stabil.

-> I was using MediaExpress only to see the incoming signal - NOT to capture anything. By the way we are using only the best and recommended SSD´s.

@Mike

-> Thanks for your reply. I will check this, but I´m sure that I am using the right slot. We are using this machine since 3 years with an Live-3D-Graphics-Renderer and I think if we would use the wrong slot also the Graphics would flicker.

-> I will also try this on another machine, with a Decklink Extreme. Maybe the input at the card is the problem.

Get back to you all soon.

Thanks Thomas

Hi again,

I have switched to a different system with Windows XP, Decklink Extreme 3D and Decklink Driver 9.0

There is still the same problem. I see sometimes black frames, even if the signal is stabil. I am watching all that stuff on different monitors - to see directly if the signal goes away.

The problem causes also trouble with the Rendering Software, which is not longer able to adapt on Video In 1.

After updating from Driver Version 7.5 to 9.0 i´ve got also a request to update the Firmware-Software, which i did. I also restarted the system.

The Rendering-Software is working well, but is still unable to use the Video-In-Channel.

Before I forget this - I have checked, that Both cards -> Decklink Extreme 3D and NVidia GTX are placed in a PCI Express 2 - slot. So this is ok.

Any other suggestion?

Cheers Thomas

[Joshua Helling]

So, to clarify, are you not actually capturing anything. The frames are just dropping while previewing the stream?

Yes that´s right.

And because the Stream in preview is dropping, the Rendering-Software is not accepting or finding or using this Input-Connector. I tryed this on 2 machines with Win XP Pro and different Decklink Extreme HD - cards.

If I have some more time, I will try it with a lower video format.