Changing fps - pulldown and removing flicker - advice needed please!

[The Big Cheese]

Hi everyone

I'm on the cusp of understanding how to transfer cine footage but I could do with some pointers please! It's a bit urgent as well, it's a Christmas present for a family member and I expected it to be a lot easier than it's turning out to be!!!

I am transferring cine film to DVD via a camcorder and a computer but there are a couple of problems:

The cine which is 8mm runs at 18fps.
The camcorder capturing it runs at 30fps (29.97) so there is a flicker on the screen.

I believe I need software which can "pull down" the video to make it run at 24fps on the computer.

From there I can use Adobe Premiere Elements 2 (my standard video editor) to slow down the 24fps footage by 25% to make it run at 18fps.

Hopefully that should correct any video and sound issues.

Please can someone tell me:
What software I can use to pull down the footage from 30fps to 24fps.

I have Adobe CS3 master collection and can ask someone who has CS4 master collection if the software in that package will work.

Thanks very much

[aedipuss]

if this is important then what you need is to send it out to a pro production house that has the proper equipment. it needs a projector and cam synced to record each frame individually one at a time. once the flicker is recorded to tape no amount of fiddling with it is likely get it removed.

if you post a small sample the folks here will look at it to see if it's possible but don't expect miracles.

[MOVIEGEEK]

Why are you capturing 29.97fps if you are in the UK?
Why do you want to convert 29.97 to 24fps?
You should capture 25fps(if possible) and make a 25fps DVD, if not then have a pro do it.

[jagabo]

Pulldown is the process of converting progressive frames (usually 23.976 fps) to 59.94 interlaced fields per second NTSC video. What you need is inverse pulldown, the process of converting interlaced video back to progressive frames. In addition, you'll probably need an antiflicker filter to remove the flickering from the lack of sync between the projector and camera. I recommend you post a sample of your video in the original digital format (DV AVI?).

[filmboss80]

The flicker you see is not so much a pulldown issue as a mechanical timing mismatch between the 8mm projector's rotating shutter blades and the electronic shutter of the camcorder. Bright frames indicate capture with the cine shutter wide open and dark frames indicate capture at the instant the cine shutter blocked the projector lens. It is not detectable by the eye, but the timing mismatch is glaringly obvious when using a camcorder. (And I too am puzzled by your use of a 29.97fps video speed in the UK. Are you trying to use an NTSC camera in a PAL country? Your video speed should be 25fps.) In order to synchronize film and video, you either need to adjust cine film speed until the flicker goes away (which requires a variable speed feature on the cine projector) or have the job professionally done.

I do 16mm film-to-video transfers all the time with a telecine projector that has a 5-bladed shutter that synchronizes 24fps motion picture film with 29.97 NTSC video. In the case of old home movies in 8mm and Super-8, I use a projector with variable speed, adjusting slowly until the flicker vanishes. You need to have the right equipment.

[The Big Cheese]

Thank you all for the quick replies, it is very much appreciated!

Unfortunately getting a professional to do it is not an option at the moment.

Excuse my newbie confusion, it's not 29.97fps at all, I'm talking complete rubbish, it's a PAL camcorder so it is 25fps.

filmboss80, your last sentence gives me some hope. The projector we are using can change the fps between 18-24fps, but we can't change it 'on the fly'. I would have to try it with one, rewind, try again etc. until the flicker (hopefully!) disappears.

Is there a particular setting you would recommend having it set to, or does it change with each cine film?


Many thanks

[filmboss80]

If only the 2 projector speeds (18fps and 24fps) are possible, then I doubt you'll completely remove the flicker. If you can tweak in between those 2 speeds, I'd try 20fps. Is there any way you can speed the projector up to 25fps? If so, your problems are solved. Even if the film is running too fast, you could later use any number of video editing software packages (like Adobe Premiere, which you mentioned) to slow down the clips that have been captured to your computer. Your first challenge right now is to eliminate the flicker.

Unfortunately, I've never done cine-to-video transfers in the PAL system, so my knowledge is limited in your particular situation. Hopefully, someone else can chime in.

[The Big Cheese]

Thanks for your reply

In my partners 'technical' terms she says she can "wazz the switch right up to the top and see what it does", but as far as we are aware it only goes to 24fps unfortunately.

Thanks for the tip though, we will certainly try it at 20fps tomorrow (it's getting late here) and see how it goes!

[manono]

Never mind. Didn't understand at first.

[The Big Cheese]

Hmmm.

We've tried it at 20fps and pretty much every variation and they all come out the same unfortunately. The flickering is pretty awful and if the footage is slowed down to 18fps for the silent 8mm stuff the flicker is really noticeable.

Getting a bit panicky now and really wishing we hadn't put this off so long!

If there are any bright ideas about how we can convert silent 8mm cine shot at 18fps to a camcorder capturing at 25fps, back to 18fps without getting the flicker I would love to hear it!

Thanks.

[jagabo]

In the absence of synrchronized shutters I would try decreasing the projectors frame rate as low as possible then filter out the dark frames/fields and decimate to the original film frames in software.

Keep in mind your camcorder is shooting 50 fields per second, not 25 frames per second (unless you have a camcorder that shoots 25 fps progressive). Try using the fastest shutter speed you can get away with. That way the difference between light and dark frames should be very clear (making the dark frames easier to detect and dispose of).

[The Big Cheese]

Thanks for your quick reply

Do you mean zooing right into the video footage and chopping out all the dark frames manually? Wouldn't there be thousands of the little blighters?

[jagabo]

Thanks for your quick reply :)

Do you mean zooing right into the video footage and chopping out all the dark frames manually? Wouldn't there be thousands of the little blighters?

Not manually. Using AviSynth or VirtualDub filters. Maybe you could post a short sample.

I would also try the other extreme: use long exposures on the camcorder. That will give less flicker but you'll get double exposures.

[The Big Cheese]

Ah, sounds good, thanks for the hint!

I've also just discovered a way using virtualdub, there is a deflicker filter for it which, on the first pass I've tried with it seems to have done an incredible job!

Unfortunately it's turned a 1.72GB file into a 14.4GB monster....not sure how it did that but I haven't really used the program before so I think I missed a setting somewhere.

I'm not sure how to post a sample to be honest, especially when the sizes I am dealing with are far to big to upload but I think we're along the right lines with the software filters!

[jagabo]

using virtualdub... Unfortunately it's turned a 1.72GB file into a 14.4GB monster...

Video -> Compression... select a codec for the output file.

[redwudz]

To add to jagabo's post concerning VD, you could use a lossless codec like Lagarith or HuffyUV for output, or to save a bit more HDD space, you could try the Cedocida DV Codec. DV is about 13GB/hour and the lossless codecs around 25GB/hour. Lagarith is more compact than HuffyUV and my preferred codec for high quality/small size.

If you don't choose a codec with VD, it defaults to RGB which will give you huge file sizes. The above codecs need to be installed, then VD can use them. All three codecs will give you keyframes with every frame, making frame accurate editing very easy, including what you are trying to do with your video. They also have low quality loss between generations if you need to process the video more than once.

VD can also frameserve the edited video directly to a MPEG encoder, eliminating a in-between file that takes up extra space. One guide for frameserving: https://www.videohelp.com/oldguides/virtualdubframeserve

[The Big Cheese]

Ah brilliant, thanks for the info, I'll try that!

I wonder, would you have any recommendations for Virtualdub flicker settings to help remove the flickering?

We have found that setting it to play at 24fps produces the least flicker, and VD helps a bit but not a lot. The default settings are:
Window size 8
Softening 10
Scene change threshold is disabled by default (256)

I have checked interlaced source as it's being captured by a camcorder.

I've tried changed window size and softening numbers a bit a t a time but I'm not noticing much difference at the moment.

[courtneye]

Hello,

I think this is the correct thread to post this question to... I hope so anyways. I'm working with 3/4" U-matic copies of 35mm and 16mm film originals. These were ingested on KEM flatbed editors (basically a camera attached to a film playback table where the camera was filming the film as it passed across a prism and projection screen- http://en.wikipedia.org/wiki/Flatbed_editor). Anyways, these U-matic copies have some flicker, most noticeably at the top of the image. I'm pretty sure this was introduced during the film to tape transfer.

Now, I'm trying to capture these U-matics as uncompressed YUY2 interlaced at 29.97fps. It seems that the flicker is more pronounced after I capture. Also, it seems that it happens at a slower rate, possibly half speed and is definitely more distracting. However... when I play the file back within the Edius software the flicker is nearly eliminated or at least happens at the same speed as it does on the U-matic tape.

Any idea why this is the case and how I could mimic this by applying some sort of filter or by using different capture settings??? Do I need to use inverse pulldown? How does it work? I don't think there's a filter in Edius specifically for this effect. I'm not sure what kind of camcorder was used to capture the U-matic copy, but I do know that it was played back at 24fps while it was being captured.

Also, the project I'm working on isn't of enough importance to go back to the original film and re-capture so I don't really have the option of re-capturing and adjusting the shutter speeds.

Thanks in advance for any info...

A wmv and dv sample file is attached, the uncompressed avi captures were too big.

[manono]

You had to give us text? Nothing showing movement? Anyway, here an XviD if it, improved and with the garbage opening frames cut out:

Yadif(Mode=1)
SelectEvery(5,1,3)

[courtneye]

Thank you for the cleaned up clip and the info re the deinterlacing filter. Was the only fix you did to apply that filter with those settings?

Also, what would you with the progressive wmv??? Is there anyway to clean that up as well? Or what type of deinterlacing would you suggest I use upon capture?

Let me know when you have a minute. Thank you!!

[manono]

What I did was bob the video and then pull out the junk frames which were in a regular pattern, the result being 23.976fps (which you said was the capture framerate). You could use a better quality bobber if you like, but the footage is so lousy that I don't really see any need to. When slowing it to the original framerate, you'd use AssumeFPS(18) or whatever it's supposed to be. For that sample, the SelectEvery line says that for every 5 (bobbed) frames, keep the second and the fifth (AviSynth numbering begins with zero). For the entire video the pattern may be different. You might have to pull out a different set of 2 frames in every 5. But, with luck, the pattern will be consistent throughout the video.

I didn't look at the WMV because I refuse to work with them and DV is better quality anyway (unless it was made from the WMV). Why you converted to WMV from the original capture is beyond me unless it was just to provide a sample. When encoding for the final format use the original cap as your source, not the WMV. That is, if the intended end result is DVD, encode the original source for MPEG-2 and forget about useless intermediate files.

Was the only fix you did to apply that filter with those settings?

Yes, except for getting rid of the junk opening frames. Other filtering can be done, such as maybe reestablishing proper black and white levels, but with only a little bit of text to go by it's hard to make specific suggestions.