UPDATED Audio video synch mysteries

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kozikowski
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Re: Audio video synch mysteries

Post by kozikowski » Tue Jun 19, 2018 3:43 am

Now you know why critical separate-sound video productions occasionally put clapboards at the front and the back of a shoot.
Screen Shot 2018-06-18 at 20.38.24.png
Screen Shot 2018-06-18 at 20.38.24.png (8.66 KiB) Viewed 110 times
"CAMERA MARK" [bang]
ACTION!!
acting.
acting.
acting.
acting.
Cut!!
"TAIL MARKER!" (holding board upside down)[bang]

The video people are looking for the picture of the zebra stripes closing and the sound people are listening for the noise.

Koz

audio_pete
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Joined: Fri Jul 26, 2013 1:03 am
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Re: Audio video synch mysteries

Post by audio_pete » Tue Jun 19, 2018 4:00 pm

Seems to be on right track (when have I heard that before)

new Change Speed much improved

automatically detects end of file check
shows length in multiple formats check
shows length in h:mm:ss + PAL frames check

eyeball on Filmora target
00:22:19 06
starting position of audio
00:23:19 04

took 5 tries to get to
00:22:19 03

3 frames difference

Tried in filmora
closer but still needs work

Will find a better mouth movement
that can pin down closer in Filmora
then
get audio to match to the PAL frame

Will let you know.

Thanks for getting me this far.

kozikowski
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Re: Audio video synch mysteries

Post by kozikowski » Tue Jun 19, 2018 4:11 pm

Nobody wrote anywhere that the error has to be constant over the course of the show. All these corrections are based on everything working normally and according to spec. You know you're in trouble when the two ends match...but not the middle. That's a maintenance or new equipment purchase problem.

Koz

audio_pete
Posts: 105
Joined: Fri Jul 26, 2013 1:03 am
Operating System: Please select

Re: Audio video synch mysteries

Post by audio_pete » Thu Jun 21, 2018 1:33 am

End of round 2

One of us won by TKO
not sure if it is me or the movie.
Audacity seemed to work as advertised, at least the latest version. 2.0.2 was little / no help.

Using Filmora identified scene
00:17:34 +16 PAL frames back of head
00:17:34 + 17 PAL frames men facing speaking
That was my target

VOB_denoise into Audacity was 00:31:27 +14 PAL

(fog of war aside: just checked the VOB opened in Audacity just now was 00:30:10 + 7 PAL
not sure why the difference but was 2.0.2 vs 2.2.2)

Working with 00:31:27 + 14 PAL length
Took 10 tries to get "men facing speaking"
down to 00:17:34 +17 matching my video mark

00:30:08 +7 PAL frames was just a bit short
00:30:08 + 6 PAL frames was just a bit too long

settled on 00:30:08 +7 PAL frames as giving the best match

BUT

took a lot of work for a queasy result
I don't think I ever watched peoples mouths so much
the film, at least my copy, was dark and mostly shot from a distance
I guess its just queasy because I "know" it is not "exact".
AND this is VOB 1 of 1 DVD, a 1 gig VOB2, and much shorter VOB 3 await
NOT to mention converting the last 2 hours of the film (1 more DVD).

I might go back to Playboy of the Western World because I like it so much
but I think Richard III and Twelfth Night will have to wait.

Thanks for the attention and help.

Plan to drop a donation in the basket when the plate comes round.

kozikowski
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Posts: 40695
Joined: Thu Aug 02, 2007 5:57 pm
Operating System: OS X 10.9 Mavericks
Location: Los Angeles

Re: Audio video synch mysteries

Post by kozikowski » Thu Jun 21, 2018 2:42 am

I don't think I ever watched peoples mouths so much
That's the curse, isn't it? I can't watch bad editing on YouTube. It makes my teeth hurt.

Koz

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