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Mark L. Pederson
01-02-2007, 04:08 PM
(1) when shooting 60fps or 120fps - what timecode is being recorded to the files in the camera? Do you set it up to base 24 first?

(2) in REDCINE, will you have the ability "restripe" timecode on export?

(3) Have you guys settled on the MetaData fields that will be in REDCODE RAW from the camera? Will that metadata pass through to the DPX headers if you are exporting to DPX in REDCINE? Any chance of a utility or tools for adding user-defined metadata fields?

Lucas Wilson
01-02-2007, 06:28 PM
(3) Have you guys settled on the MetaData fields that will be in REDCODE RAW from the camera? Will that metadata pass through to the DPX headers if you are exporting to DPX in REDCINE? Any chance of a utility or tools for adding user-defined metadata fields?

Hey Mark (or Pliny?),

I'm curious here... since you specifically mention DPX, based on SMPTE RP215 or 266M - what header information do you expect to use most frequently?

And how would you expect that information to flow from a camera (like RED ONE) to an application (like SCRATCH?) :)

Cheers,

Lucas Wilson
------------
Arbitrator of Minutiae
Assimilate, Inc.
Los Angeles

Mark L. Pederson
01-02-2007, 08:09 PM
It's Mark (couldn't you guess from the avatar?)

Hey Lucas -

I specifically mention DPX because that is what we intend to convert to for color grading in SCRATCH -

My wheels have been turning lately on ways to use metadata during editing and VFX work -

I'm not familiar with 266M - can you send me a link to description or a RP216 vs. 266M for dummies?

Can I add user defined meta data fields to the DPX header - or our we married to SMPTE?

Lucas Wilson
01-02-2007, 10:28 PM
I'm not familiar with 266M - can you send me a link to description or a RP216 vs. 266M for dummies?

My bad - it's actualy 268M

http://smpte.org/smpte_store/standards/index.cfm?scope=0&CurrentPage=11&stdtype=smpte

When you're on that page, just look for 268M. That's just the spec, though. A really good description of DPX files and how they are structured - metadata and all - is available in the "File Interchange Handbook" by Brad Gilmer. It's available on Amazon.

And again, my bad - it's RP215 - that's what I get for trusting my memory. RP215 is also available for purchase on the SMPTE site.


Can I add user defined meta data fields to the DPX header - or our we married to SMPTE?

Both. There is a *ton* of room in the SMPTE spec for totally user-defined metadata. More than you'll probably ever need. But - a DPX file is a DPX file and it is defined by SMPTE. So, if you veer outside the spec, it isn't a DPX file anymore. :)

Lucas
-----
Reader of Really Boring Specs
Assimilate, Inc.
Los Angeles, CA

Stuart English
01-03-2007, 09:20 AM
The way timecode works in the camera is as follows -

You establish your "project frame rate" for example 24 fps. This is the frame rate that you typically capture in, and also the frame rate that you play back, edit and present in.

Hence that's your timecode counter baseline.

Then if you capture at speeds faster or slower than that, you just run the clock counter faster or slower.

Then when you play the clip back, you have a slow motion sequence, running at 24 fps and with valid 24 fps timecode.

So no need for Varicam-like duplicate frame and timecode re-striping.

Mark L. Pederson
01-03-2007, 10:31 AM
thanks Stuart - that's what I assumed.

There are other reasons however, in post, that one will want to "restripe" timecode - hoping that option is built into REDCINE -

Mark L. Pederson
01-03-2007, 10:36 AM
Both. There is a *ton* of room in the SMPTE spec for totally user-defined metadata. More than you'll probably ever need. But - a DPX file is a DPX file and it is defined by SMPTE. So, if you veer outside the spec, it isn't a DPX file anymore. :)

That is the answer I wanted.

I will draft up what I think could be done with metadata specifically for feature film workflow and see what you think - If you like it - we can gang up on Graeme and Rob - or get the other guy from Holland to code it ..

So, if I add a bunch of user defined fields and it's not a DPX file anymore - it's an OHD file (Offhollywood Digital) - will Scratch handle it all the same ..?

Rob Lohman
01-03-2007, 04:21 PM
offhollywood: I'll keep that feature in mind, at the moment it's not in there. I can imagine it would be impossible to re-link footage after you've changed the timecodes if you would ever need that.

Thomas Mathai
01-04-2007, 12:36 PM
For me, it seems timecode isn't the way to go with data centric cameras.

I hope SMPTE works on a digital equivalent to keycode.

I would think it should be unique enough a sequence that no two cameras can generate it.

Also software developers need to pass through metadata, it doesn't matter how much metadata you include into a DPX file, it's going to useless if it gets striped out in the render.

Lucas Wilson
01-04-2007, 12:47 PM
For me, it seems timecode isn't the way to go with data centric cameras.

I hope SMPTE works on a digital equivalent to keycode.

Thomas - there are several ways of doing this. But almost all of them involve timecode as it is such an entrenched standard. But combining timcode/tapeID with a UUID or some version of a UUID provides a unique identifying mechanism.

Keep in mind that Keycode is not necessarily unique either!


Also software developers need to pass through metadata, it doesn't matter how much metadata you include into a DPX file, it's going to useless if it gets striped out in the render.

Agreed. Now talk to Adobe, Apple, Avid, Autodesk, Quantel and get them to agree. :)

Best,

Lucas Wilson
------------
Metadata Shepherd
Assimilate, Inc.
Los Angeles

Alex Boothby
01-04-2007, 01:47 PM
I would think it should be unique enough a sequence that no two cameras can generate it.


You said it all Thomas! This would be such a wonderful thing to aim for, and very do-able given the right mindset. I'm a fan of the timecode-calculator approach, where the timecode is derived from (and subservient to) much more meaningful ID data.

Here's an earlier thread on this topic, from some crap, backwater, has-been site:

http://www.dvxuser.com/V6/showthread.php?t=76103

Thomas Mathai
01-04-2007, 02:43 PM
Thomas - there are several ways of doing this. But almost all of them involve timecode as it is such an entrenched standard. But combining timcode/tapeID with a UUID or some version of a UUID provides a unique identifying mechanism.

Keep in mind that Keycode is not necessarily unique either!



Agreed. Now talk to Adobe, Apple, Avid, Autodesk, Quantel and get them to agree. :)

Best,

Lucas Wilson
------------
Metadata Shepherd
Assimilate, Inc.
Los Angeles



I don't mind having timecode included. I figured it would make sense to have something that isn't user set.

I always wondered if keycodes repeated and how often, but I haven't experienced that.

I would expect all the developers would allow metadata to pass through, since there isn't a reason not to. The user base will become more vocal about it when they realize they need better ways to manage their data.

Developers seem to not want to understand that users don't do everything in a single app, they mix and match based how well one app does a function over another.

tj williams
02-04-2007, 05:40 PM
Is there going to be an equivalent of user bits. to label" rolls time of day a,b,c, etc camera, which operator, script page etc etc.

If so will it allow us to simply hook up the laptop on loading the mag or??