Video Sync

Hi,

My monitor, running on Black-magic HDMI output has a terrible 6 frames delay.
When I set the delay in Devices to 280 The pictures are sync to the sound… Nice!

But not so nice is that all sound is delayed by 280 Ms.
Any sync dubs are impossible!

Can we advance the video instead. I can do it manually by dragging the videfile in Nuendo 7 frames earlier, but that causes other issues (like remembering to put it back) can we not set a video advance setting in the Device setup. Only in stop mode it should bypass the advance so you can go to a certain frame and drop a effect on the right spot.

With this advance video you can actually do a synchronious voice over! Or a leadvocal with the Videoclip running in sync!!

please do this quick! :laughing:

Frank

Hello Frank,

I do not understand these 2 sentences. Which delay did you set exactly?
Do you use Nuendo 6.0.2 or 6.0.3?

Best Regards,
Bodo

Hi,

it’s the delay you can set in the device setup on the video tab.

See attached screendump.

This 280 ms setting will delay the audio output of Nuendo.
I would like to play the video 280 earlier.

Frank K
Schermafbeelding 2013-04-18 om 13.12.16.png

Awforgot

It’s Nuendo 6.02 (64 bit) (on a Mac OSX 10.8.4)

Frank K

Hmmmm … maybe this is a mac-only thing, but AFAIK dialing a delay into the Blackmagic card doesn’t affect the audio.
The whole purpose of that delay is to get audio & video in sync.

We use Syncheck to measure the delay.
So, if the audio & video would be out of sycn, Syncheck would report it.

Unless I totaly misunderstood the question.
Fredo

And that’s how it works on my systems…

Hi Guys thanks for checking and replieing! But you totally missed the point.

My video is perfectly in sync with the audio if I set the delay (in the device setup) to 280 ms (this confirms to my LG screen having a 7 frame delay on playback).

But it being just sync is not enough.
It is sync because the audio gets the 280 ms delay. This is not a question it is a fact!!

My questions is to advance the video by 280 ms.
Advantage is that besides the pictures on my screen being perfectly sync, also a live voice-over dub has no delays (a live recording with the pictures running along IN SYNC). The live recording with direct monitoring being direct and without delay.

(it is possible to advance the video, it can be done manually by moving it 280 earlier on the timeline, but it is better to do it in a system setting. Better too because in stop mode the advance video setting should be ignored by the system, this to jog or move to the correct frame to drop a soundeffect to it)

Come on guys, if you do videowork you would understand what I mean. It has nothing to do with a Mac or a PC difference!

Frank K

Why do you think this is a fact. Did you measure it somehow?

I think it’s a fact that the offset you set up in the video device setup window only effects the video. :wink:

BTW Nuendo 6.0.3 improved the video engine latency to be similar to Nuendo 5.5.

It would be very unlogic to set a delay in a video setting while the videopicture is already late (7 frames or 280 ms).
Nuendo is not a typical video programm, while i monitor over a digital mixer to set the delay on audio while using finalcut pro to have sync video and audio I can tell that the audio is delayed and the video is unafected by the delay setting.
If it would affect only the video picture and not the audio the it would do exactly what i request and advance the video by the setting. I can tell you it does not do this!
Maybe it will convince you if you import a video with speech only (audio as well as video). Play this on screen (press f8) then set a vast delay in the top most video setting like 800 ms, then tell me what happened? The video is early or the sound is late? Well the sound is late, prove is connect a microphone and try record a dialogue sync to the picture, just speak along. (This just to test. On screen the video is pretty much sync without the delay setting, depends on the monitor you use. Typicaly a one frame offset is hard to see for a untrained eye)

Tell me the result!
It is not different for a black magic card.
Frank K

If you set the video delay as a latency in Device Setup, Nuendo does the right thing:

  • It shoots out the picture earlier than the sound, just enough to compensate for card and pix monitor latency, so you’re watching in sync.

  • But it does not apply any compensation when you’re scrubbing, jogging, shuttling, or whatever you want to call it. So you can spot or still-frame, or use edit mode (pix automatically moves along with the start of an event you’re placing) and know that your timing is accurate.

This is a lot better than manually sliding the pix on your timeline.

As far as voice-over… I haven’t tested if there’s a way to compensate VST connect for the talent’s distant monitor. I suspect not. But who cares about 250 ms latency on a voice-over? You can fix it while you’re editing, cleaning breaths, and doing other stuff. Or if you’re lazy, just dial -250 ms into the track control.

“Who cares about a 250 ms on a voice over?”

Are you nuts?

It’s like driving a race car with a flat tire, who cares?

Frank

To be sure I understand this correcty.

You say that when setting the latency to 0 ms, you can hear the input of your microphone (Direct Monitoring) without any delay.

When dialing the 280ms delay into the Blackmagic Card’s video settings, the input of the micorphone get’s delayed by 280ms.

Is that correct?







BTW, Jay is talking about recording a voice at distance (different locations over the internet) through VST connect. Has nothing to do with real time recording as you describe it.

Fredo

Yep,

that is the whole purpose of this request. Latency is bad enough (athough only 4 ms on my system) but with the delay set in the device settings its unusable (the delay adds up to the latency because ALL AUDIO is delayed to match the video)
A voice over is just a s important as a leadvocal, 280 ms delay is unworkable.

Here we go again, the delaysetting of 280 Ms should advance the video track. It should playout the video 280 Ms earlier, as if you would drag the video track 7 frames early in your arrangment while leaving the audio as it is (audio being the audio out of the video track or the imported OMF).
I know time is a relative thing but please try and understand this. The result of my request will be sync video to audio (with a variable setting) while maintaining minimal latency so sync live recording can be done without delays (other than the inherent latency of your audio card, or none with direct monitoring)

Frank K

Frank,

I just tested this on one of our systems.

-RME Madi set to the lowest buffer size (32) ==>>> no (detectable) latency within the mic path
-RME Madi set to higher buffer size (1024) ==>>> Large latency within the mic path

-Added a videotrack
-Set output of video through Blackmagic card
-Set latency of the Blackmagic card to it’s maximum (1000)
-RME Madi set to the lowest buffer size (32)

==>>> no (detectable) latency within the mic path

So, on my system, the latency dialed into the Blackmagic card has no effect whatsoever and is not in relationship with the latencies of my Soundcard.

There must be something different in our setups.
We are on Win7, so it might have something to do with the OS handling the soundcard differently.
Maybe Oliver of Bodo can clear this up?


Fredo

Yo,

sorry being late with response, had to save myself in hospital :slight_smile: (I’m fine)

On return I got “video card not responding”, had to reinstall the Blackmagic drivers. Upgraded to Nunedo 6.03 as well.
All seems fine now, probably just the upgrade handled it!!!

senks for your patience!

Frank