Flickering in animation

Showing 1-20 of 20 messages
Flickering in animation Huck 9/12/09 7:33 AM
I exported an animation to an .avi file.  When I play it the lines
have a flickering quality.  Does anyone know why this is?  Is there a
way to avoid it?

Huck
Re: Flickering in animation r 9/12/09 8:42 AM
are you using a mac?
Re: None Flickering in animation Colin Holgate 9/12/09 8:55 AM

Would have to see it to be sure, but it could be some sort of moire  
effect.

"r" asked if you're using a Mac, but the Mac version doesn't do export  
to AVI, so it's a PC (or Windows at least). Maybe r was thinking about  
whether the edges get anti aliased, which they do under Windows but  
not Mac.

Any chance you could post one of your animations somewhere for us to  
see, and also to then suggest how to make the file smaller?


Re: None Flickering in animation Huck 9/12/09 11:33 AM

I uploaded the file, RiverDiag-6Story.avi, to the Files section, but I
don't see how to make a link to it for you here.  (Excuse my
complaint, but Google Groups is so lame in this respect.  Other forums
make it easy to attach a file to a post).

Huck
Re: None Re: Flickering in animation Colin Holgate 9/12/09 12:20 PM

On Sep 12, 2009, at 2:33 PM, Huck wrote:

> I uploaded the file, RiverDiag-6Story.avi, to the Files section, but I
> don't see how to make a link to it for you here.

That's ok, I coped!

The problem seems to be compression artifacts from using Cinepak as  
the video codec. Unfortunately it seems not to be possible to use any  
other codec. See here for a typical thread on the topic:

http://www.pushpullbar.com/forums/sketchup/10348-i-cannot-change-codec-animations-use-always-cinepak-codec.html

If changing the codec to Microsoft Video 1, or to Full Uncompressed,  
actually worked, then you would have better options for getting a good  
quality, and yet low file size animation.

Here are some files to illustrate the issue. First an export of my  
test scene from Windows SketchUp 7, having chosen Full Uncompressed  
(but it still used Cinepak):

http://xfiles.funnygarbage.com/~colinholgate/video/fullqualityboxes.avi

and here is the same scene made with Mac SketchUp 7, as a QuickTime  
movie, and an MPEG-4 file (in case you can't play QuickTime movies):

http://xfiles.funnygarbage.com/~colinholgate/video/movingboxes.mov

http://xfiles.funnygarbage.com/~colinholgate/video/movingboxes.m4v

If the first of those two links work, then no need to try the second  
one.

The AVI one is 3.6 megabytes (for 4 seconds), and has the twitchy  
feeling in the edges. The other two are 550 kilobytes, and use H.264,  
and look a lot nicer.

Cinepak was developed about 16 years ago, and is sometimes included in  
compression settings because it's been around for so long, and so is  
supported in Video For Windows, Windows Media, and QuickTime. It's  
just unfortunate that choosing the better codecs doesn't work.


Re: None Re: Flickering in animation Colin Holgate 9/12/09 12:31 PM

On Sep 12, 2009, at 3:20 PM, Colin Holgate wrote:


http://xfiles.funnygarbage.com/~colinholgate/video/fullqualityboxes.avi

It seems our server doesn't allow direct linking to AVI files. Here's the Cinepak AVI saved as a QuickTime file:



Compared to the 1/7th of that size H.264 movie:



Re: None Re: Flickering in animation Huck 9/13/09 3:27 PM
Hi Colin,

Both of those look great compared to what I am getting.  But are those
only available from the Mac SU?  Or, how did you get them?  and how
can I get that quality?

Huck
Re: None Re: Flickering in animation Colin Holgate 9/13/09 3:38 PM

On Sep 13, 2009, at 6:27 PM, Huck wrote:

> Both of those look great compared to what I am getting.  But are those
> only available from the Mac SU?  Or, how did you get them?  and how
> can I get that quality?

Hopefully you can see how much worse the fullqualityboxes one is  
compared to the movingboxes one. The artifacts in my test were  
essentially the same as the ones in your test, but the angles of the  
buildings in yours may have shown up the issue more.

Unless someone can say otherwise, exporting under Windows is stuck  
with Cinepak, regardless of what you select. The only suggested work  
arounds involve exporting image sequences, but then you would need a  
program that was able to combine the sequence again.


Re: None Re: Flickering in animation Huck 9/22/09 5:22 PM
I think I discovered why the flickering line problem occurs.  A thin
line at a slight angle across the screen “steps” down to the next row
of pixels as it crosses the screen.  In some places a grey surface
next to the line may be white for a short distance at the “step”.
When the image moves, these steps move.  Where 1 row of pixels is
black and in the next image the next row is black, your eye may put
them together causing them to appear to be 2 pixels wide.  All these
changes combine to display a flickering line.  Well, that is my guess.

I don’t know what could fix this.  Any ideas?
Re: None Re: Flickering in animation Colin Holgate 9/23/09 6:18 AM

On Sep 22, 2009, at 8:22 PM, Huck wrote:

> I think I discovered why the flickering line problem occurs.  A thin
> line at a slight angle across the screen “steps” down to the next row
> of pixels as it crosses the screen

What you were describing is called aliasing. It's what antialiasing  
fixes. But even with antialiasing you can get flicker effects if  
either the antialiasing isn't very good, or if the video codec is bad  
at handling thins lines or stepping. The movies you showed looked like  
there was antialiasing, but that Cinepak was doing a poor job of  
handling those edges.


Re: None Re: Flickering in animation Huck 9/23/09 12:39 PM
I tried selecting File>Export>Animation, then click the “Export type”
dropdown menu and select “jpeg”
This gives a series of jpeg images.  The quality of the images looks
better and when I hand animate them with Windows Picture & Fax Viewer,
it looks better.

Do you know anyway to combine these jpegs into a video file?
Re: None Re: Flickering in animation Colin Holgate 9/23/09 12:57 PM
Use PNG rather than JPEGs, that way you're dealing with perfect  
pictures and not compressed ones.

I would use QuickTime Player 7 (Pro version, $30). That has an Open  
Image Sequence option, that will let you point at the first of your  
image sequence files, it will pick up the rest of the files  
automatically, and you can set the frame rate that it should play back  
at. You then have a movie that you can export to various video  
formats, though not WMV.

Maybe there are PC tools that can do the same? Others here may well  
know.

Re: None Re: Flickering in animation Huck 9/24/09 9:55 PM
HEY!!!
I used Quicktime Player (Not Pro as far as I can tell, but I did buy
Pro a long time back, but it doesn't seem to be on my laptop which is
what I'm using).  It has a File>Open Image Sequence, which will play
the jpeg images I generated from Sketchup (File>Export>Animation,
select "Export Type" = jpeg).  They are way better than the .wmv files
I generated from Sketchup.
Now I just need to figure out how to put them into a single video file
that an ordinary person can play.

Huck
Re: None Re: Flickering in animation Colin Holgate 9/25/09 8:32 AM

On Sep 25, 2009, at 12:55 AM, Huck wrote:

> HEY!!!
> I used Quicktime Player (Not Pro as far as I can tell, but I did buy
> Pro a long time back, but it doesn't seem to be on my laptop which is
> what I'm using).

Go here:

http://store.apple.com/

and click on Account (between the Help and Cart buttons on the right).  
In there you will see a Downloadable Software Purchases item, click on  
that. You'll have to sign in, but then you see a list of software that  
you have bought, and your QuickTime Pro number will be listed there.  
In QuickTime Player look for the Registration option, and type your  
name and paste in the reg number.

Once you're up and running with QuickTime Pro you can then do an  
Export / Movie to QuickTime Movie to get your image sequence out to  
something playable by others. If you're daunted by the options, look  
for the Export for Web menu item, and try some of the presets in there.


Re: None Re: Flickering in animation Huck 9/25/09 11:03 AM
I guess I did have Pro installed.  I just saved the movie and uploaded
it.  It is in Files with the name RiverDiag-6StoryFromStills.mov
http://groups.google.com/group/SketchUp/web/RiverDiag-6StoryFromStills.mov
Can you tell me how to make a proper link to files uploaded to Files?

 I’m thrilled with the quality but the size is scary.  This file is 37
images, 1280x960, played back at 29.97 FPS.  The file is 5.2MB for a
bit more than 1 second of play.  Also, Windows Media Player won’t play
the file which is .mov.  Any idea how to get it into a file format
that is more available to anyone?
Re: None Re: Flickering in animation Huck 9/25/09 11:06 AM
PS
Windows Movie Maker won't import a .mov file.

On Sep 25, 8:32 am, Colin Holgate <co...@verizon.net> wrote:
Re: None Re: Flickering in animation Colin Holgate 9/25/09 11:40 AM
I hadn't reported back yet for two reasons. First, I don't think the  
antialiasing out of SketchUp is very good. Also, I couldn't work out  
how to animate through all of the scenes, only from the first to the  
second.

Your Save As file still would have the large JPEGs in the video track  
(I still say you should use PNGs, not JPEGs). What you need to do is  
Export the movie, not Save As. Using the Export for Web, and choosing  
the Desktop option, gives a folder with html and QuickTime files that  
you can post online. Just taking one of the movie files gives this:

http://xfiles.funnygarbage.com/~colinholgate/video/river.mp4

It's at 720x540, which is smaller than your original size, but in  
doing that it improves the antialiasing. You could do the image  
sequence at a very large size, then coming down to the smaller size  
would given even better antialiasing.

That link, which I hope you can play, uses H.264 for the video, and  
it's under 480k instead of the over 5 megabytes of your JPEG version.


Re: None Re: Flickering in animation Huck 9/25/09 9:57 PM
Colin,

To animate all the scenes:
click Windows>Scenes
highlight Scene 3 and holding down Shift highlight all through Scene
12
Then click "Include in Amimation"
Then play or export and it will give the whole animation.

I downloaded the file.  However, Windows Mediaplayer won't play it.
QuickTime would play it.

I tried the Export to Web but what I got didn't seem to have an mp4
file at all.  What did I do wrong?
Re: None Re: Flickering in animation Colin Holgate 9/25/09 10:06 PM

On Sep 26, 2009, at 12:57 AM, Huck wrote:

> I tried the Export to Web but what I got didn't seem to have an mp4
> file at all.  What did I do wrong?

I renamed it in the hope of making it work for other MP4 players. Oh  
well. The other option is to use Flash, which I can make, but not  
everyone can. I'll do a test of that using all 12 scenes. I'll set my  
machine making it as I go to bed!


Re: None Re: Flickering in animation Colin Holgate 9/26/09 7:55 AM
I'm going to start a new topic in a moment to explain the steps I took  
in my last test. I'll title it "how to export nice animation". I'm  
just doing that to help out the people who subscribed to these threads  
and can't get unsubscribed!