Question about component playback speeds...

[Jim Arthurs]

Okay, I don't think anyone has brought this up yet...

...say you want to play back your recorded footage and digitize into your NLE via the analog component outs of the HVX (a workflow I'll need to do until Vegas/Premiere and my own VelocityHD have comprehensive P2 support).

First big assumption; the component analog outs auto adjust to either (1920 x 1080) or (1280 x 720) depending on the file being played back. I assume this is the case and not 720 scaled up to 1080 or your 1080 material scaled down to 720. Again an assumption.

Now a question... what will be the timebase for the camera when playing back via analog? If the footage is 1080 the answer is easy, 29.97i... since 23.98 and 29.97p are recorded as interlaced 29.97i in all cases. (will the camera ADD 3:2 and 3:2 Advance to the analog playback of 23.98 material?)

BUT if the footage is 720p then the question becomes this... will the camera's playback rate be ADJUSTABLE to accommodate the various playback scenarios? Most likely is that 720p is only played back at 59.94fps. Then your 29.97 and 23.98 clips will be speeded up unless the camera is adding duplicate frames to pad out to 59.97.

And since there's no other info except pure video signal coming from the analog component outs then there's no way to detect and post-strip the duplicate frames. You would be forced to only work at 59.97p!

Remember, no flagged frames or meta data coming out of the analog outs.. the camera has to be SMART to make this work. Here's what I'm hoping...

The analogy here is that the camera needs to be switchable to a particular time-base for analog playback just like the timeline on your NLE. Set your NLE timeline to 29.97 and a 59.94 clip will automatically be .5X slowmo. Set your NLE to 23.98 and your 24fps material plays back correctly, other speed clips are slowmo or fast motion. on that timeline.

Ideally, there's a menu setting similar to this...

ANALOG OUT PLAYBACK TIMEBASE

-720P 59.94
-720P 29.97
-720P 23.98

Any thoughts? One note, I've left out all SD analog out discussion in this post on purpose.

One clue to how playback of various 720p frame rate clips is handled would be to see how they're displayed when looking at them on the LCD/viewfinder.

Regards,

Jim Arthurs

 

[Haakon]

We've asked several times in posts about how the camera will handle the variable framerates in-camera, and if we'll be able to preview those results on the LCD, but as far as I know, there hasn't been any response yet.

 

[Barry_Green]

Don't know the answer, but a clue is in the most recent Panasonic HVX brochure where it said something on the order of that you could play back variable-frame-rate clips and preview the "speed effect". That would imply that you could set the timebase, because a 60p clip is "real time" if you're editing in a 60p timeline, and it's 2.5x slow-mo if editing in a 24p timeline, so there has to be some way to differentiate.

I am pretty sure that the analog outputs will be either 1080/60i or 720/60p. I would also presume that duplicate frames would be added on the analog outputs to conform variable-frame-rate acquisition to a 60p timebase. But, you do have some good questions, and hopefully we can get some more concrete answers after Nov. 8th when the fully-functional models hit the Panasonic US office.