Canon EOS 5D Mark II for european use

[Mathieu Kassovitz]

1)

What's the best method for converting from 30p to 24p or 25p ?

Same effect as 24p or 25p recording after converted ?


2)

Any tip how to avoid the 50Hz flickering ?


Merci


MK

[Toenis Liivamaegi]

NO WAY!.

Best regards,
Greedy H* Apes



*halfblind of the rising sun you know, the sun that sets too early.



.

[Soeren Mueller]

Mathieu, a "real" conversion would involve some serious amount of frame blending or "intelligent" algorithmic morphing (similar to what tools like Twixtor or Furnace are doing for retiming) - or else you could only use conventional frame blending, but this would produce quite some ghosting depending on the type of footage. It's quite a mathematical challange to stuff 30 frames per second into 24 or 25 frames.

Another option would be perhaps to simply use all frames but at the slower speed... although this would lead to aprox 17-20% slomo of the original. And I assume this would become already quite noticeable?! (you would have to slow down the audio accordingly without a pitch shift while maintaining it's quality)

So it's sort of a pain in the a... (and requires quite some processing power in post).

But as I read somewhere.. rumour has it that Canon is thinking about adding 24 and/or 25fps support via (firmware) upgrade soon after release date. As far as I know this is not yet confirmed.
(which would of course also help us here in Europe regarding 50Hz flicker - as here you only had the choice to either make sure nothing flickers / prevent it somehow while shooting or try to fix it in post - but fixing flickering in post is most of the time an even heavier task than the 24/25<->30 fps conversion, sometimes even completely impossible depending on the image contents)

Cheers
-Sören

PS: I saw you posting in the "Mobile HDMI recording" thread too... of course this would make quite an interesting combination: a 5D Mark II (with 24/25fps recording) connected "uncompressed" via HDMI to a portable HDMI->Cineform encoder/recorder... :) ... only thing missing perhaps some firmware enhancements in the Canon for better manual control while "filming"...

[Jerome Marot]

Originally Posted by Soeren Mueller

Mathieu, a "real" conversion would involve some serious amount of frame blending or "intelligent" algorithmic morphing (similar to what tools like Twixtor or Furnace are doing for retiming)

Compressor, which comes bundled with finalcut on the Mac can use motion estimation and prediction when doing framerate conversion, so I suppose that these techniques are fairly standard nowadays.

Note: fairly standard or not, those techniques are also extremely computer intensive. It takes a long, long time...

Originally Posted by Soeren Mueller

But as I read somewhere.. rumour has it that Canon is thinking about adding 24 and/or 25fps support via (firmware) upgrade soon after release date.

Only time will tell. We don't even know whether the chip can be read at 25fps...

[Louis Mostert]

I have played around with converting 30p to 24p/25p. I've used Twixtor, but it interpolates between cuts. You need something with scene detection. Maybe Algolith Algosuite 2?

[Soeren Mueller]

Jerome, you're right about that it is fairly standard - fairly standard in a way for software publishers to have some sort of conversion function in their software. Nevertheless it still holds true as I said: it's not only quite computer intensive but also relies on different "pseudo intelligent" algorithms which will never always work 100% right on every kind of footage. It's not a simple equation to go from x fps to y fps when you don't want to have simple frame blending etc. with heavy ghosting/smearing etc.
If you want to have a nicer result you have to use motion estimation / prediction etc.pp. all the "funky stuff". Some solutions work better than others.. some solutions have internal defaults that you can change, others have more user options so you can tweak it. One shot works with values xyz ok, other shots need other values, some shots don't work at all or only with heavy manuel tweaking (had this on a recent RED shoot, not funny in 4k).

It's the same with for example AFX' retimer (Furnace) and also other tools (Twixtor, and the bigger ones etc.) ... sometimes they "magically" work out of the box for "artifical slomo", sometimes you can really really weird motion artefacts etc. (like Louis said, for example strange interpolations on a cut - especially on dissolves!)

So it would really be a sort of worst case solution...

[Don Miller]

Originally Posted by Soeren Mueller

But as I read somewhere... rumour has it that Canon is thinking about adding 24 and/or 25fps support via (firmware) upgrade soon after release date. As far as I know this is not yet confirmed...

I can't think of a single time Canon has added functionality to a DSLR after release. It's likely the 5DII is intentionally limited. Future more expensive product will have more options.

I find the emphasis on 24p over 30p doesn't make a lot of real world sense. There's advantages to 30p, and nothing is going to make very high quality video look like film. Progressive is what matters. 1080 30p in the dark is pretty cool.

[David Parks]

It's doable but painful.

You would import .mov 30p into a 1080/60i project. Edit your sequence.

Then export to:

DVFilm Raylight Codec for DVCPROHD

60i to 24p.

Cheers.

Disreagrd as HDV or DVCProHD. This is an old tutorial, but the software should work as advertised.

[Soeren Mueller]

But that was for "24p stuffed into 60i" (pull-up) ... that's not the same as true 30p, so this would not really work as expected.

And please lets not start a discussion (again) about 30p/60p/70p being better than 24p...

[Jerome Marot]

Originally Posted by Soeren Mueller

Jerome, you're right about that it is fairly standard - fairly standard in a way for software publishers to have some sort of conversion function in their software. Nevertheless it still holds true as I said: it's not only quite computer intensive but also relies on different "pseudo intelligent" algorithms which will never always work 100% right on every kind of footage. It's not a simple equation to go from x fps to y fps when you don't want to have simple frame blending etc. with heavy ghosting/smearing etc.
If you want to have a nicer result you have to use motion estimation / prediction etc.pp. all the "funky stuff".

I meant: I think that what you call the "funky stuff" has become fairly standard. In any case, compressor uses motion estimation and prediction to compute intermediate frames when doing framerate conversion (in the highest settings). And it is perfectly able to detect different movements in different parts of the picture (e.g: the image pans to follow a car, with cars passing in the other direction in the background).

You have to realise that motion estimation and prediction is necessary for mpeg compression, so that the program code has already been written. Apple has realised that they could reuse it for framerate conversion, and I suppose that they are not the only ones with that idea.

[Soeren Mueller]

Yes I know, as I'm a software developer "by day" with a bunch of imaging/image analysis/compositing plugins projects under my heap.
But it is _by far_ not only motion detection/estimation.. which is also not a "perfect science", there are many many parameters to tweak and more then one way to do it - all with a different outcome. In video compression the difference is not that visible because there it just makes a difference in the compression ratio.
But in the case of frame rate conversion it is the combining of several frames into one, doing morphing kind of stuff, even having to come up with totally new frames (if it's from 24fps to 30 or more for example) - so as I already said two times: it's like what Furnace and Twixtor are doing for retiming. It will not always work perfectly, it simply can't.
Of course the easier way to do it - blending or duplicating/discarding - will always work.. but either you will end up with totally jerky motion (duplicating/discarding) or quite a smeary/ghosty picture (frame blending).
Sorry, but there is no magic algorithm available, yet. ;)

[Jerome Marot]

I never said it worked "perfectly" or it was magic. I said that I supposed that framerate conversion using motion estimation was fairly standard. Now, if you tell me only Furnace and Twixtor (and Compressor) are doing it somewhat right, I stand corrected.

But yes: it would be better if the 5D would allow 24 or 25fps. Since I live in PAL land, I am even more eager to know what Canon has planned for this market. But my hopes are relatively low.

[Mathieu Kassovitz]

Any Furnace, Twixtor or Compressor, etc . . . examples or previous experiences?