Help to track down source of "jitter"

[ukmpoam]

Can anyone help me track down where in the process from DV capture through editing & DVD production / burning on to DVD -RW with Studio 8 occasional "jitter" is introduced?

I have tried defragmenting my HD, optimising for the application rather than back ground functions, turn off screen saver etc. I have also tried reducing the "video quality" from 8000K bits/sec down to 7000K bits/sec.

The system that I have is described in my profile which I presume you can view. I am using Studio 8 with the latest driver updates for capture, editing & burning of the DVD -RW.

Obviously if anyone can any suggestions as to how I can resolve this problem I would be grateful or advise to how to track down the source of the problem would also be appreciated.

Thanks,

Andy.

[Capmaster]

Does your capture card have its own IRQ? With Win2K and XP you have to watch that ....it'll try to share them and that's bad news for video capture.

[ukmpoam]

Capmaster,

That was quick.

To be honest I don't know if it has its own IRQ, I'll have to check. I'm running Win2K, do you think the same problem applies with this?

Andy

[Capmaster]

Well I've been waiting all day for you to post so I could answer you ...j/k I just happened along and you had just posted it a minute before.

The Windows NT-based OS'es like Win2K and XP use IRQ sharing for the PCI cards. You can go into device manager and instead of clicking on the device, click "computer" and select properties. That'll show you a window where you can look at DMA channels, IRQ, memory addressing, etc. If the IRQ is shared with another device you should be able to disable sharing in the machine's CMOS setup. You don't ever want that shared since video is so resource-intensive. When the card requires something it sends an interrupt request to the CPU. If it's shared the CPU might have to service an existing one on that IRQ before it can service the one from your video card. That might mean it waits a little longer. In the meantime you might get dropped frames, cache underflows, etc. Almost anything can happen but it frequently shows up as stuttering video.

[ukmpoam]

Capmaster,

So you were right, my 1394 firewire host controller is sharing an IRQ.

Being as you know what you are talking about I have another couple of questions;

1. How do I disable / enable again the devices that are sharing with it?
2. What is the implication of disabling ACPI IRQ Holder for PCI IRQ Steering? (The other sharing application is for my All in Wonder Pro Cature card which I won't be using when using the firewire card for DV capture).

Andy.

[Baldrick]

It is isn't the dvd authoring. Moving your topic.

[Capmaster]

Capmaster,

So you were right, my 1394 firewire host controller is sharing an IRQ.

Being as you know what you are talking about I have another couple of questions;

1. How do I disable / enable again the devices that are sharing with it?
2. What is the implication of disabling ACPI IRQ Holder for PCI IRQ Steering? (The other sharing application is for my All in Wonder Pro Cature card which I won't be using when using the firewire card for DV capture).

Andy.

Andy,
See PM reply.

[Gabriel_Brazil]

Dear friends,

My DVApp shows me the message : there is no dv camcorder device on this system. I noticed that my Firewire card is sharing irq 9 with another 3 cards...is that the problem ?

Thanks...

[Cobra]

Please start a new thread instead of taking over an older one!