Best quality 30p to 24p workflow... mac, or combined with PC?

[joshcali]

Ok,
so does anyone have the best quality method for converting 30p to 24p.

Right now I'm shooting with the 5dmark2, and I am hearing of re-timing workflows within final cut pro,

BUT I'm actually hearing good things about avisynth and plugins that do motion interpolation to create the needed frames.

so what's the story? anyone have the right idea?

[PuzZLeR]

Are you talking about taking a film source and converting it to 23.976fps?

With AviSynth, this would be a simple IVTC procedure using tfm() and tdecimate() (along with maybe a color space conversion beforehand). But you'd need to re-encode, which should be done after edits.

Not sure how to do this on a Mac though.

If you can upload a small sample, and tell us what playback format you wish to encode to, it would help.

EDIT: Correcting only a keyboard error.

[edDV]

Yes need more info on camera or other source details. Also why do you want 24p if you shot 30P?

If you shot 30p but want 24p methods range from dropping frames (jerky) to reinterpolation of a new a new frame sequence (artifacts and blurry). Best to shoot in the frame rate you want in your export edit master.

[PuzZLeR]

I agree with edDV with the artifacts.

Going from 29.97fps to 23.976fps could only work properly/fluidly, with a re-encode, if and only if, you have a film source in your stream as I mentioned.

This could be either:

-seeing 2 interlaced frames every 5 on playback

or

-seeing 1 repeat frame every 5 if it's a progressive playback

Then yes, you would get a more efficient encode using basic IVTC procedures as I described, but I wonder if indeed your camera is producing such streams to begin with.

If you don't have the above criteria and you use interpolation and "filters" you will definitely introduce such imperfections, as edDV pointed out. Then I wouldn't personally recommend gong to 23.976fps at any rate despite any efficiency it would produce.

But a sample would indeed be very helpful to determine this if the O/P can provide one.

[joshcali]

Well, basically I have a job where some footage was shot 24p
(two cameras one hv20, and another panasonic in AVCHD)

and then I have the output from my 5d mark II which is 30p

right now the idea is to convert everything to 24p for editing in final cut pro 7, and eventual output to blue ray. two of the sources are already 24p, it's only the 5D Mark II footage which is 30p, so I'm looking into methods of converting the 30p footage shot with the 5D mark II to 24p.


so far the most promising is the MVTools route, although I was hoping for a solution that was all mac based. but I ain't gonna be picky

[aedipuss]

you might want to check carefully the 24p footage you have. most likely neither camera produced real 24p. the hv20 doesn't for sure, it's 24p in a 30i wrapper. the only way to get real 24p out of it is to ivtc it to a lossless avi.

try mediainfo on the files.

[PuzZLeR]

Didn't realize you wanted it for blu-ray - yup, at the HD rez you will need 23.976fps.

Then yes, MVTools is indeed an arguably best solution if you can get the right parameter combination that works for you depending on your souce - but it will never be perfect anyway. It will be slow and you will still get artifacts.

And I doubt you will find any Mac solution that will be (much) better at any rate. You can still edit in Final Cut, but may have to do the final encode separately if you can export the streams untouched other than edits.

Do check first if it's 24p video within a 30p stream - most ideal scenario if applicable.

Otherwise, is there any way you can get the Canon to shoot 24p (or 24p within 30p)? Personally, after this thread, I will definitely make sure that any HD camera I buy next will shoot in 24p, or 24p within 29.97 (progressive or interlaced).

[edDV]

Not an easy project.

Here are your instructions for HV20 pulldown removal.
http://www.hv20.com/forumdisplay.php?f=32
http://eugenia.gnomefiles.org/2007/07/13/canon-hv20-24p-pulldown/

Consult Google for the Panasonic AVCHD. FCP can reinterpolate 30p to 23.976p but expect artifacts.

[joshcali]

Guys, I am so thankful for the dialog, discussion and help.

for the HV20 I'm good... it's true 24p, just wrapped in 60i
there's a great program JES Deinterlacer which reconstructs the 24p frames from within the 60i wrapper.


so HV20... great 24p: ok
panasonic... AVCHD... 24p: ok
5D Mark II... true 30p going to 24p: Ugh

thinking about mvtools, and what I can do.
most of my shots on the 5D are locked off with people moving only.

[poisondeathray]

If you have after effects for mac/pc you can use pixel motion, but the resampling will give similar artifacts to mvtools. But mvtools (using mflowfps or mvflowfps) is about 5-10x faster to render with similar quality. There are other 3rd party plugins such as twixtor for AE, but they aren't much better than the built in pixel motion. If you are very picky, what you can do is try a few interpolation methods, and select the best frames from each. There just isn't a good way in post for 30p=>24p.

[manono]

If there's a significant amount of the progressive 30fps stuff, it'll certainly be easier, and might even be better in the long run, to just hard telecine (encode the 3:2 pulldown into the video) the progressive 24fps. Apparently, at least some of your sources are like that already ('it's true 24p, just wrapped in 60i '). After all, that's how it's done on retail DVDs and can easily be done for Blu-Ray, I think.

An alternative would be to encode the 24fps (with pulldown) sections and 30fps (no pulldown) sections separately and join them during authoring. That way everything gets to remain progressive with none of that artifact-ridden and slow-as-molasses-in-January frame creation. I do this quite a lot for DVD. I have no idea whether or not it's possible to do it for Blu-Ray.

[PuzZLeR]

Just reading back now, unless I misunderstood, do you mean to assemble 30p content with some of your 24p content in the same edit workflow? (I was thinking them as separate projects actually.)

In that case, as an alternative, I would look into converting to (common) editable formats beforehand (with what method you choose to use regarding fps). Look into Cineform (does 24p). Then you can do a final encode after your project.

I personally have an aversion to relying on any editor's internal encoder for the final result, which it must do afterwards if it accepts different formats on the timeline since this will disqualify any "smart render export" for best results with a better stand-alone encoder later.