OnLocation codecs

I

Igor Bineli

Member
I was wandering what are the codecs that OnLocation writes when capturing HVX200 footage...
I made a test with AVI T2 and the GSpot ( a very helpfull little soft... http://gspot.headbands.com/ ) tells the the codec is Pinnacle DVHD100 @23,976fps.
Is this right?
Then I asked myself what are the color sampling used by this codec and I didn't find anything about it on the web.
So... is there a practical method for discovering what color sampling a codec uses?
Another question, does the OnLocation writes 60P footage?
If does, how do i set?

thanks !
 
OnLocation stores the camera-original footage, not a new codec. So if you're capturing HVX footage it's storing DVCPRO-HD (also known as DV100) at 4:2:2.

If you record 720/60p, OnLocation will store 60 progressive frames.
 
How do you connect the HVX to a PC laptop with Onlocation?

Only via FW or is USB2 possible?
What output settings in the camera?


Are there many dropped frames or is this a reliable way to store?
I intend to use a Dell 2.16 Ghz Core 2 Duo with a 7200 SATA HDD.

As reliable as FS100 or P2?
 
thanks Barry!
but is there a way of telling what color sampling a codec uses?
scaling up the footage? some color matting? plugins?
 
I couldn't use OnLocation monitor for the HVX200 when in 720/24PN.

Is that possible ?

Thanks,
Ulisses
 
ulisses said:
I couldn't use OnLocation monitor for the HVX200 when in 720/24PN.

Is that possible ?

Thanks,
Ulisses
Click to expand...

Because the "N" stands for "native", it means that it's a native data-stream, and not a real-time video format, therefore it can't be carried by a real-time video signal like Firewire.

You can't ever send "pN" footage over Firewire in real time .. hence the reason for the availability of "p" (without the N) in the cameras too.

- Mikko
 
Igor Bineli said:
thanks Barry!
but is there a way of telling what color sampling a codec uses?
scaling up the footage? some color matting? plugins?
Click to expand...
Well, the test would be to put some red and green dots on a frame and then compress it through the codecs in your NLE; you'll be able to tell pretty quickly what color sampling the codec's using if you know what to look for.

But of the HVX codecs,
DV NTSC: 4:1:1
DV PAL: 4:2:0
DVCPRO NTSC: 4:1:1
DVCPRO PAL: 4:1:1
DVCPRO50: 4:2:2
DVCPRO-HD: 4:2:2
 
The AVI files that OnLocation captures are the native DVCPRO data, as provided by the camera. OnLocation just takes the FireWire stream and captures it into a file.

Now, what codec will be used to decode the stream? That's a more complicated answer. OnLocation CS3 does install a Video for Windows (VfW) decoder for use with most PC-based NLE's. The footage can also be decompressed by other DVCPROHD codecs, like the Pinnacle DVHD100 codec. All DVCPROHD codecs use a 4:2:2 color sampling rate, as that's the spec that Panasonic uses.

OnLocation always looks to the FireWire port for capture. It won't look at USB2 or other ports, because these don't send data in a DV/DVCPRO format.

It is a very reliable way of capturing, because there's a LOT of work "under the hood" ensuring there will never be a dropped frame under normal circumstances. There are only 2 circumstances where (in theory) a dropped frame could happen:

The first if if the FireWire cable becomes unplugged. (!) If the signal is lost, OnLocation will wrap up recording the current clip, so your recorded footage will be fine up to that point. If I'm moving the camera around a lot, I gaffe the cable in place just to avoid this.

The second is if the drive can't write the data fast enough for a long period of time. OnLocation uses a RAM buffer to keep from dropping frames, but there is a limit to how much that can hold. There's an indicator in the upper right of the DVR that shows the amount of buffer left. In normal operation, it should barely show a small blue line, indicating the buffer is staying empty. If that blue bar ever turns red and fills completely, OnLocation would have to drop frames. However, under any normal situation, that should never happen, and you should have plenty of warning time to wrap up recording before the buffer fills entirely.
 
mikkowilson said:
Because the "N" stands for "native", it means that it's a native data-stream, and not a real-time video format, therefore it can't be carried by a real-time video signal like Firewire.

You can't ever send "pN" footage over Firewire in real time .. hence the reason for the availability of "p" (without the N) in the cameras too.

- Mikko
Click to expand...

On location is able to record 24pN from a 24p signal
So you can use the monitor and record less frames.
 
Barry_Green said:
Well, the test would be to put some red and green dots on a frame and then compress it through the codecs in your NLE; you'll be able to tell pretty quickly what color sampling the codec's using if you know what to look for.

But of the HVX codecs,
DV NTSC: 4:1:1
DV PAL: 4:2:0
DVCPRO NTSC: 4:1:1
DVCPRO PAL: 4:1:1
DVCPRO50: 4:2:2
DVCPRO-HD: 4:2:2
Click to expand...

Q. What to look for? can you tell us?
 
KarlSoule said:
The second is if the drive can't write the data fast enough for a long period of time. OnLocation uses a RAM buffer to keep from dropping frames, but there is a limit to how much that can hold. There's an indicator in the upper right of the DVR that shows the amount of buffer left. In normal operation, it should barely show a small blue line, indicating the buffer is staying empty. If that blue bar ever turns red and fills completely, OnLocation would have to drop frames. However, under any normal situation, that should never happen, and you should have plenty of warning time to wrap up recording before the buffer fills entirely.
Click to expand...

I have a PCMCIA sata card plugged in my laptop (HP Pavillion zv6000, with 1 GB RAM) with a 2.5" sata Hard disk; no droped frames, fast recording.
 
While OnLocation stores the camera original footage, what happens when you choose to record in "QT" vs AVI T1 or T2 in the menu? Doesn't OnLocation then wrap the original footage in a quicktime wrapper of some sort? If so, is this an Apple codec that they use for that or some Adobe designed thing?

I ask because I have been having serious problems using OnLocation's quicktime clips, captured on my Windows laptop, on my MacPro FCP set-up. I started another thread on this but so far no one has any suggestions. I am able to edit those quicktime clips successfully, but then I can't export that edited sequence back to a quicktime movie. This leads me to believe that the quicktime clips created by OnLocation on Windows are somehow not fully compatible with quicktime on Mac. Does that make sense?

Maybe if I can understand how OnLocation does the original quicktime wrapping, maybe I can find out some clues to solving this problem.
 
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