FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

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woocaash
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Joined: Tue Dec 26, 2017 10:36 pm

FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by woocaash »

FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP


Windows 10 Enterprise LTSB 64 Bit

I have a video piano concert that was recorded with variable frame rate of 30fps.
I am using Adobe Premiere Pro and was advised by adobe to try converting this video file with handbrake.
I followed the instructions and set constant bitrate 29.97 fps and loosless quality rf=0.
The file I received was indeed constant 29.97, same quality but the whole clip was a little bit shorter.
I need the clip to be the same exact length what the original because it has to be perfectly sync to the audio.

Are there any other settings that i have to change ???
for example
Anamorphic / Modulus from the Picture tab
"Optimise Video" settings for Encoder Preset, Level, Tune, Profile on the Video tab
or maybe there are plenty of options / settings on Advance Tab once you enable it.

I am completly lost.
Thank you everyone for helping me out
rollin_eng
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Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by rollin_eng »

Could you please post your logs, instructions can be found here:

https://handbrake.fr/docs/en/latest/hel ... y-log.html
woocaash
Posts: 5
Joined: Tue Dec 26, 2017 10:36 pm

Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by woocaash »

https://docs.google.com/document/d/1700 ... sp=sharing

Thanks for helping me out

I tried 2nd time
I changed to placebo (5 min clip in 4 hours), set encoder to high /film and turned off filters

The file is shorter than the original

Thanks
rollin_eng
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Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by rollin_eng »

Try the nightly build with the a/v sync option.
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s55
HandBrake Team
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Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by s55 »

How much is it out by?
[14:54:24] vfr: 9000 frames output, 11 dropped and 0 duped for CFR/PFR
That should be with audio sync corrected so you shouldn't have a sync problem.
rollin_eng
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Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by rollin_eng »

Looks like the audio is not being handled by HB, maybe being muxed in after?
woocaash
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Joined: Tue Dec 26, 2017 10:36 pm

Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by woocaash »

i don't need any audio from this video
i only need this video to have exact same length
it is only short 5 min clip, i need the video to be perfectly sync with audio in a long run

original 5:00:08
converted 4:59:28
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JohnAStebbins
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Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by JohnAStebbins »

How are you determining duration?

According to the log, your original is *not* 5:00.08. It is 5:00.28.
Also according to the log, 9000 frames were output. At 29.97fps framerate, the duration is 5:00.30.

The difference between 5.00.28 and 5.00.30 is less than 1 frame duration which is exactly what I would expect.
woocaash
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Joined: Tue Dec 26, 2017 10:36 pm

Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by woocaash »

yes you are right log shows 5:00:28
when i open the converted file in adobe premiere pro it shows 4;59;28 ; original 5:00:08
this is i think 11 frames (
this is were i get the numbers from

correct me maybe i am wrong

1 sec is 30 frames
in the log it says 11 frames dropped (my guess is 11 frames = approximately 1/3rd of a second ???)

can you tell me what is the best way to check the length (exact duration) duration ?
if it is less than one frame i can accept it


When i open both files in handbrake and check duration in activity log i see:

original 5:00:28
converted 5:00:32

are those duration numbers 28/32 frames or or 1/100 of sec

thx
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JohnAStebbins
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Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by JohnAStebbins »

correct me maybe i am wrong

1 sec is 30 frames
Your wrong. You selected 29.97 fps output framerate. So 1 second is 29.97 frames in your output file.
in the log it says 11 frames dropped
Your source was 300.28 seconds and 9011 frames.
The number of frames when converting to 29.97fps will be 300.28 * 29.97 = 8999.39.
I.e. There will be about 11 fewer frames in a 300.28 second video at 29.97fps than in a 300.28 second video at 30fps.
When i open both files in handbrake and check duration in activity log i see:

original 5:00:28
converted 5:00:32
Yup, those are the correct durations
are those duration numbers 28/32 frames or or 1/100 of sec
I don't understand the question
Deleted User 11865

Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by Deleted User 11865 »

woocaash wrote: Thu Dec 28, 2017 12:05 amoriginal 5:00:28
converted 5:00:32

are those duration numbers 28/32 frames or or 1/100 of sec
The latter.
woocaash
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Joined: Tue Dec 26, 2017 10:36 pm

Re: FRAME RATE / convert var to constant changes the length of the clip PLEASE HELP

Post by woocaash »

thank you everybody for clarifying everything for me
i am very surprised how helpful this community is and how fast it went
I wish all the forums are as active and helpful
happy new year and all the best
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