I cant remove the jitter, right?

Post » Fri Jun 05, 2015 11:42 pm

I believe I am trying to do something that I should not be doing, I?m moving an image across a screen too quickly, see the example video on Vimeo. The image jumps too many pixels from frame to frame resulting in jitter, jumps, or blur. Pick the term you like, but you get the idea.

Before I give up on the idea of sliding images across a screen, thought I would get confirmation that I?m wasting my time.

https://vimeo.com/109651805

In case it matters, I'm using VP13 and rendered in both 23.976 and 29.97 fps. No significant difference if any.

Thanks
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neen
 
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Post » Sat Jun 06, 2015 12:20 am

It will not help the situation using 29.97 unless the original footage was shot at a higher frame rate, it will still need motion interpolation. However it looks to me as if you are using an interlaced source and have the frame dominance reversed. In project properties, try changing the field order and see if that helps.
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dean Cutler
 
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Post » Fri Jun 05, 2015 10:53 pm

Jitter is a function of field rate: the few the number of fields per second, the more jitter you will see, especially when the camera pans horizontally.

Notice I said fields, not frames. There is nothing that makes interlaced video less prone to jitter, but since the whole purpose of interlacing is to increase the number of "events" per second, and since most interlaced video is either 50 or 60 fields per second, that is WAY more than the 24 or 30 frames per second that you are contemplating using.

So, if you don't like jitter, shoot PAL or NTSC interlaced ("50i" or "60i"), or shoot 60p.
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Stryke Force
 
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Post » Sat Jun 06, 2015 12:15 am

Hi, I read the note posted by Rich and then tried a simple (equivalent?) reproduction of using track motion to slide a jpeg across a background. I'm using 25P and initially, rednering to a MC mp4 (720p) format, got very similar jittering. Then used exactly the same project, but rendered to AVI (Magic YUV codec) and got a WAY smoother result. How so?
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MR.BIGG
 
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Post » Fri Jun 05, 2015 11:04 pm

try this: watch your vimeo video but stand progressively farther away from your screen.

Did that fix the problem??
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luis dejesus
 
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Post » Fri Jun 05, 2015 11:14 pm

Make the video on vimeo downloadable.
That way we can see if they've done something, or if its a delivery / bandwidth issue.
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Johnny
 
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Post » Fri Jun 05, 2015 11:07 pm

I haven't looked at your video, but there's an old-school film rule (based on 24fps/180 degree shutter) that a maximum panning rate on a non-moving subject is seven seconds to cover the width of the frame. If you're panning a still, you'd need to add some motion blur to make up for the shutter rate. As with most rules there are exceptional circumstances, but it's a good guide for 24p. You can interpolate for other progressive frame rates.

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Cheryl Rice
 
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Post » Sat Jun 06, 2015 12:23 am

Also make sure the generated media matches the final render resolution.
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Bloomer
 
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Post » Sat Jun 06, 2015 12:08 am

Thanks to all that replied. I'm sorry I wasn't clear, the checkerboard pattern was intended to simulate photographs, it is not video. I thought this was the best way to show my problem. The checkerboard pattern is a JPEG image representing photos.

I have made the video downloadable but here are some details. These parameters represent what I uploaded to Vimeo.

Bit rate mode : Variable
Bit rate : 9 941 Kbps
Maximum bit rate : 20.0 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
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Darian Ennels
 
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Post » Fri Jun 05, 2015 11:02 pm

Check out the examples on my last post in this thread:

www.designstudioschool.com/forums/ShowMessage.asp?ForumID=4&MessageID=896747

You have to look download and install the player to see the magic. That Sony player does a sort of bob deinterlace that is really wonderful is why.
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Lilit Ager
 
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Post » Fri Jun 05, 2015 11:43 pm

It's pretty simple, you're not using a high enough frame rate to move the graphics that fast. The integration time of the eye is about 40fps, anything lower than that will produce the judder you're seeing. That's part of why television was interlaced to begin with, to get a temporal resolution of 59.94 individual images per second. I never shoot 24p, ever.
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JD FROM HELL
 
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Post » Fri Jun 05, 2015 11:18 pm

Now that I've looked at the files in the post I must echo what John Cline is saying. You can only move an object in a video so fast as compared to the frame rate. The faster the frame rate, the more motion you can use.

Having said that, in your case you could probably keyframe in some blur on the axis of the motion. I have done that quite successfully on quick pans and tilts where the video was shot with too short a shutter speed.
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Shelby Huffman
 
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Post » Fri Jun 05, 2015 11:05 pm

I'm still scratching my head.

Please see my post above. I've given 2 examples below. They are from the same project, 720p, 25 fps.

If I render with MC mp4 template I get this: youtu.be/Snf7JaDXggM

If I render with AVI (Magic YUV codec) then render mpeg 2 (720p, 25 fps) I get this:youtu.be/2_fYOuvScDw


I see a substantial difference, even more when I look at the "original" AVI (720p 25 fps), vs the MC mp4 (720p 25 fps), but I had to rerender the AVI through to an mpeg to enable upload to Youtube.

Any thoughts on why the difference?
Dramatically different level of "jitter". I find this surprising.
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+++CAZZY
 
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