Does anyone have any tips for synching sound with video? I've used VidEdit,
but I'm having trouble getting the video and sound to synch as a cyclical
segment. I measured the length of the animation and matched a similar length
of audio, but it comes out short?

Grim

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I came up with a method of synchronizing sound and video using POV by
using the actual spectral dataof the sound file to control various
object parameters using POV 3.1's new text-file commands.  So far my
attempts have been specialized hacks that don't generalize easily, but
you should know that it's possible.
On the looping sound-video synchronization thing, unless the tempo
corresponds precicely to the frame rate you are using, a cyclic
animation will drift versus the beat.  The solutions are:

(1)  change the tempo of the sound source so that it is a multiple of
the frame rate.
(2)  change the frame rate to match the tempo
(3)  render the "loop" as one long sequence, with the tempo matched exactly.

You will be able to see the results of my POV-sound experiments shortly.
 I'll post once those pesky final 2 minutes are filled up.

-Eric

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Sounds to me like you have a professional package for this?

GrimDude
vos### [at] arkansasnet

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GrimDude wrote:
> 
> Sounds to me like you have a professional package for this?

Nope.  Here are the rough details:

I used a shareware oscilliscope program to output frequency data to a
text file.  Then, using a text editor I formatted the data into the form
required by POV.  Within the scene file, the frequency data is read in
and used to scale and texture objects, carefully coding so that the time
index of the current frame is synchronized with the music (!).  One
could create, (like i have), a sphere that pulsates with each bass note.
 Since each "frame" of sound data is much shorter than 1/30 second, a
"snapshot" approach can generate a very accurate but somewhat jerky
animation.  I'm working on ways of smoothing out the animations without
bogging down too much under all the extra MB's of sound data.
I also plan to modify this code for lip-sync.
If you're really interested in the nitty-gritty, let me know and I'll
share some old code--but be warned it's all specialized and full of
goofy junk.  Also, I work on a mac, which shouldn't make much of a
difference, but sometimes there are compatability issues.

Ya know, tho_... some of my best results in sync-ing audio and video
have come from purely random collage.  It's amazing how things just seem
to line up on their own.

-E

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Chalk one up to ingeniuity.
Way to go, Eric. It's a fine concept, what I wondered though is the
first posters question of syncing with the actual audio file once again
back out of the render sequence. The player or creator programs might
still offset the image/sound. Just being pessimistic.
Now for the optimistic comment, "This is a great thing you are doing".


Eric Andersen wrote:
> 
> GrimDude wrote:
> >
> > Sounds to me like you have a professional package for this?
> 
> Nope.  Here are the rough details:
> 
> I used a shareware oscilliscope program to output frequency data to a
> text file.  Then, using a text editor I formatted the data into the form
> required by POV.  Within the scene file, the frequency data is read in
> and used to scale and texture objects, carefully coding so that the time
> index of the current frame is synchronized with the music (!).  One
> could create, (like i have), a sphere that pulsates with each bass note.
>  Since each "frame" of sound data is much shorter than 1/30 second, a
> "snapshot" approach can generate a very accurate but somewhat jerky
> animation.  I'm working on ways of smoothing out the animations without
> bogging down too much under all the extra MB's of sound data.
> I also plan to modify this code for lip-sync.
> If you're really interested in the nitty-gritty, let me know and I'll
> share some old code--but be warned it's all specialized and full of
> goofy junk.  Also, I work on a mac, which shouldn't make much of a
> difference, but sometimes there are compatability issues.
> 
> Ya know, tho_... some of my best results in sync-ing audio and video
> have come from purely random collage.  It's amazing how things just seem
> to line up on their own.
> 
> -E

-- 
 omniVERSE: beyond the universe
  http://members.aol.com/inversez/POVring.htm
=Bob

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Eric this is terrific. Something I have been trying figure out on the PC
side of things. I'm looking at trying to interpret .wav files to generate
frequency and amplitude data and creating a text file for POV to use in an
animation. Not there yet but heading that direction. Keep developing!

Pat

Eric Andersen wrote:

> GrimDude wrote:
> >
> > Sounds to me like you have a professional package for this?
>
> Nope.  Here are the rough details:
>
> I used a shareware oscilliscope program to output frequency data to a
> text file.  Then, using a text editor I formatted the data into the form
> required by POV.  Within the scene file, the frequency data is read in
> and used to scale and texture objects, carefully coding so that the time
> index of the current frame is synchronized with the music (!).  One
> could create, (like i have), a sphere that pulsates with each bass note.
>  Since each "frame" of sound data is much shorter than 1/30 second, a
> "snapshot" approach can generate a very accurate but somewhat jerky
> animation.  I'm working on ways of smoothing out the animations without
> bogging down too much under all the extra MB's of sound data.
> I also plan to modify this code for lip-sync.
> If you're really interested in the nitty-gritty, let me know and I'll
> share some old code--but be warned it's all specialized and full of
> goofy junk.  Also, I work on a mac, which shouldn't make much of a
> difference, but sometimes there are compatability issues.
>
> Ya know, tho_... some of my best results in sync-ing audio and video
> have come from purely random collage.  It's amazing how things just seem
> to line up on their own.
>
> -E

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GrimDude <vos### [at] arkansasnet> wrote in message
news:36ad68b6.0@news.povray.org...
> Does anyone have any tips for synching sound with video? I've used
VidEdit,
> but I'm having trouble getting the video and sound to synch as a cyclical
> segment. I measured the length of the animation and matched a similar
length
> of audio, but it comes out short?
>
> Grim
>
    Yo!  /Check demo called MAGPIE PRO.  www.thirdwish.com
Probably best sound editing software around.  forget about the
crash dummies program with bones, surface targeting, etc.
Worth every penny in "wheaties" mode. You'll be surprised &
amazed.  Hats off to Miguel Grinberg!
  Majuba

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Uh, Gene? Thanks, but uh...your system date is porked.

GrimDude
vos### [at] arkansasnet

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Hmm, third visit here and "Not Found" every time. :(

GrimDude
vos### [at] arkansasnet

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