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Cinema DTS - main thread
#11
The version of Timecop I have is the US Warner Home Video - Action Double Feature (paired with Bloodsport).
Ive wanted to pick up the German Concorde release due to its AVC encode rather than the US VC1, but I believe there the same master (?)
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#12
(2020-05-06, 11:34 AM)CSchmidlapp Wrote: The version of Timecop I have is the US Warner Home Video - Action Double Feature (paired with Bloodsport).
Ive wanted to pick up the German Concorde release due to its AVC encode rather than the US VC1, but I believe there the same master (?)
Check this out.

https://caps-a-holic.com/c.php?a=1&x=542...0&i=2&go=1
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#13
Just out of curiosity when resampling/slowing down to 23.976 48kHz are you processing each individual reel or a stitched together file?

I only ask as when I did my first Cinema DTS sync, processing the files in eac3to resulted in clipping being detected and corrected which usually meant a small amount of -ve gain. However I found that different reels were being attenuated by different values so I gave up the individual approach and went to processing a single merged file. That way the level adjustment was consistent across the whole film.
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#14
(2020-05-09, 07:47 PM)zoidberg Wrote: Just out of curiosity when resampling/slowing down to 23.976 48kHz are you processing each individual reel or a stitched together file?

I only ask as when I did my first Cinema DTS sync, processing the files in eac3to resulted in clipping being detected and corrected which usually meant a small amount of -ve gain. However I found that different reels were being attenuated by different values so I gave up the individual approach and went to processing a single merged file. That way the level adjustment was consistent across the whole film.

I did all on a per-reel basis.
Each reel processed to a 5.1.wav out of foobar2000.
Then using eac3to to resample and slowdown.
Then synced to video in premiere.

Ive been looking at a different approach since and I'm going to
Each reel processed to 5.1.wav out of Foobar2000
Synced to video in premiere by changing the video fps to 24
Then eac3to.

Would the transcode to 5.1.wav out of foobar2000 cause clipping?

Eac3to did not detect any when I ran it through, but it may be already there.
Some of the wav form structures looked like they had been a little compressed but I thought that may have been the actual mix.
I wanted to get through the process and get something finished to study if you know what I mean Smile

EDIT: eac3to picked up clipping when I resampled the LD mix.
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#15
I noticed that even without the LFE extraction, clipping seems to occur sometimes in the raw decoded files. Not sure why.
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#16
Ive just tried the replaygain option in foobar2000. http://eolindel.free.fr/foobar0.9/Replaygain.php
I'm converting to 5.1.wav files using the information from using the 'album' data.
Which was a gain of -0.76db

I'm going Re-Sync to video in premiere by changing the video fps to 24.
Then do the speed change and resample.
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#17
I wouldn't do that ReplayGain thing. The plugin itself most likely already outputs clipped data, so reducing gain won't really help, plus changing the gain introduces rounding errors.
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#18
It's possible the clipping was always there, baked into the print master
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#19
Well, analogue tape doesn't clip, it saturates, but yeah its possible the digitized version had this. However it actually looks like the signal is limited to be slightly below 0 dB (clipping) for most of the runtime, with only occasional clips. Which makes me suspect that the master doesn't clip, but the conversion to Cinema DTS, due to the lossy nature of it, results in imprecisions that lead to the clipping. From what I read, the audio signal is split into multiple frequency bands and then added back together at the end. Imprecisions along the way could easily result in clipping I think.
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#20
So I dropped the replaygain and just went straight untouched convert to 16bit 44kHz 5.1 wavs for each reel.
I synced them in premiere to a 24fps conformed video and rendered out a 16bit 44kHz 5.1 wav (It's under the 4gb limit, not sure what I will do when its a film in length puts it over that. Probably render it in an .avi container?)

Running it through eac3to now as a complete file has given me a clipping and 2pass flag.
This then process it with a -1.86db gain!
Would this not cause 'rounding errors' mentioned earlier?

Files sync up to the original 23.976 render.
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