I'm working on an audio sync and found that the DVD track I have contains some audio artifacts. Click? Pop? I'm not sure what the term is. For context, it's a film from the 1940s.

Here's a very short sample (ignore the hiss): https://voca.ro/1jBzL2dJmRNC

What it looks like on waveform:



And on spectrogram. It's the highlight in the low frequencies.


My questions:

• What's it called? Pop? Click?
  
• What's the best way to remove them? When there's no dialog, I can duplicate an adjacent segment to cover it. Otherwise, Izotope's "De-plosive" seems to work. Just wondering if there's a more proper tool because "De-plosive" is described as targeting "consonant speech sound."
  

More info can be found here:
https://blah-ray.blogspot.com/search/lab...%281948%29

Synced and level matched to the US blu-ray. Tape artifacts cleaned up via Izotope RX.
FLAC, mono, 339 kbps, 48 kHz, 16 bits

Looking for a Dolby stereo (2.0) LaserDisc or DVD track for the title - The Firm 1993
IMDB Info - https://www.imdb.com/title/tt0106918/

The audio can be out of sync etc., Will do the sync myself and share it to the community.

Regards

Bootleg restoration fan/hobbyist over here. Hope to one day contribute to this fine site, but for now will be content to poke around.

According to Blah-ray Blogpost, even though the mono mix on this dvd is in a lossy format, it sounds excellent than the Arrow and Polish Pro-Motion blu-rays where despite them being formatted in a lossless codec, it sounds like they took the audio from the Criterion dvd and applied a lot of strong noise reduction to the point where it sounds like it was underwater. The Criterion DVD sounds like it has minimal, if any, changes at all with the noise intact and the audio sounding clear.

However, there has been no update on whether the blu-ray from the Milestone Films Vol. 3 set sounds better or worse than the other blu-rays or the DVD. So for now, the DVD is the best sounding version of the audio I've heard.

I'm having a bit of trouble trying to sync the dvd mono track to the Blu-ray since it seems to desync as the film progresses. I was wondering if anyone wants to sync the audio to the blu-ray, here's the link to the audio track:
https://drive.google.com/file/d/1sCd2OYj...Jwg0Z/view

Spectrograms show that Kino's mono track is identical or very similar to the German MGM BD, which makes sense, considering MGM likely supplied the audio.

Per Blah-ray, the German BD has additional filtering on top of Criterion BD, and Criterion is the least terrible of the bunch.

Although they both sound bad, I can say there is still an audible difference between the two tracks, especially in ambient sound like the constant rain outside. The rain actually sounds very different, e.g. around 1:04:45 (UHD timestamp), with Kino sounding muffled and lifeless in comparison to Criterion.

Notes on the sync:

• Criterion BD is presented in 23.976 fps, while Kino UHD is 24 fps. I've sped up Criterion's audio to 24 fps.
  
• Criterion opens and closes with the MGM lion. Kino opens with United Artist logo instead. Well, I had to let go of that lion roar
  
• Criterion missed a frame in the middle of a shot (how??), between frames #102216, 102217. This is BD timestamps 1:11:03.259-1:11:03.301, or UHD timestamps 1:10:49.467-1:11:49.509.
  
• After accounting for the above, Criterion and Kino's A/V syncs still diverge very often, sometimes by up to 50-90ms. I've tried to compare them, but I found myself to be fairly tolerant of A/V desyncs. So, for simplicity, I've mostly kept to Criterion's sync seeing how nobody has complained in the >10 years since their BD came out.
  

I've been fairly active over at The Star Wars Trilogy forums and have been involved in some restoration work there.

After seeing several links to this site, I thought I'd give it a try.

It seems like there's alot of good posts here, and much valuable technical information.

Glad to be a part of the community!

Moshrom covered this back in the day: https://blah-ray.blogspot.com/2018/01/ci...-1988.html

According to him, the PCM 2.0 mono on the now-OOP 2013 Arrow UK 25th Anniversary BD was basically flawless. Judging from the cover art, I'd guess the 2017 Arrow US BD is probably identical.

Unfortunately, the same can't be said for Arrow's 2020 UHD. It sports a PCM 1.0 track instead of the previous 2.0 mono, but Arrow didn't simply re-encode the previous master as 1.0. Below is a spectrogram of the UHD's mono (my own disc), compared against 2002 Spanish Lauren Films DVD (I came across it on the Russian site). I've tried to match the spectrogram settings on Blah-ray.



And for reference, here's Moshrom's spectrogram of the 2013 Arrow BD:



It's clear that Arrow applied a low-pass filter to their UHD beginning at ~16kHz. Corroborating this is professorwho's post on BR:

professorwho Wrote:The PCM mono track sounds pretty good. I did detect some minor noise reduction at points, but it’s nothing too severe to my untrained ears, at least.

Leaning... leaning... leaning on the everlasting arms on MGM DVD mono... safe and secure from all the crappy Kino Lorber audios.
This is the most detailed track so far, much better than the Kino UHD mono (which is worse than previous compared); DVD MGM NTSC R1 mono synced to Kino Lorber UHD, pm for the track.
Previous info: https://blah-ray.blogspot.com/search/lab...%281955%29
Input: AC3, 2.0 mono, 192 kbps,
Output: FLAC, 2.0 mono, 48 kHz, 16 bits

P.S: As bonus can also share the commentary available from Criterion to Kino UHD, all in sync; Format: FLAC, 1.0 mono, 48 kHz, 16 bits

Hi everyone, I'm excited to be part of this preservation/restoration community
Have a nice day