Hey everyone!

I've been seeing lots of mentioning of tracks being "downmixed" from the 5.1 to 2.0 stereo or mono. 

How are people able to tell it is a downmix as opposed to a separate mono mix? Is there an analysis tool people are using? Just very curious.

My Laserdisc Wishlist to sync:

The General (1927) [LV21476] (piano score by William Perry)
2001: A Space Odyssey (1968)
Blow-Up: Criterion (1967)
Life of Oharu: Criterion (1952)
Grand Illusion: Criterion (1937)
Sansho the Bailiff: Criterion (1954)
The Seven Samurai: Criterion (1954)
The Third Man (1949)
Walkabout: Criterion (1971)

What is the minimum bit-depth to get good audio quality?

• Dynamic Range: How Quiet is Quiet? - http://web.archive.org/web/2013030317153...Range.html
  
• Why Compact Discs Sound Great - https://kenrockwell.com/audio/why-cds-sound-great.htm
  
• Audio Myth - "24-bit Audio Has More Resolution Than 16-bit Audio" - https://benchmarkmedia.com/blogs/applica...-bit-audio
  
• The great audio myth: why you don’t need that 32-bit DAC - https://www.androidauthority.com/why-you...ac-667621/
  
• The 24-Bit Delusion - https://www.mojo-audio.com/blog/the-24bit-delusion/
  
• DSD vs. PCM: Myth vs. Truth - https://www.mojo-audio.com/blog/dsd-vs-p...-vs-truth/
  

• 24-Bits Makes Sense! - https://www.realhd-audio.com/?p=922 [it seems not; read first comment]
  
• 24bit vs 16bit, the myth exploded! - https://web.archive.org/web/201202010845...h-exploded
  
• Audibility of a CD-Standard A-D-A Loop Inserted into High-Resolution audio Playback - http://drewdaniels.com/audible.pdf
  
• Audio Myth -"DSD Provides a Direct Stream from A/D to D/A" - http://web.archive.org/web/2015090300422...a-d-to-d-a
  
• MQA: A Review of controversies, concerns, and cautions - https://audiophilestyle.com/ca/reviews/m...ions-r701/
  
• High Resolution Audio: A History and Perspective - https://www.google.com/url?sa=t&rct=j&q=...x90N7LcwHz
  

• BD25 with animated menus that look and behave like the official Criterion discs, with a background video, pop up menus and resume function
  
• Video taken from the 4k Remastered Blu Ray
  
• Original chapter stops used on the Laserdisc
  
• English 2.0 PCM from the laserdisc (thanks Alexpeden2000 and Zoidberg)
  
• Isolated Score AC3 from the laserdisc
  
• Audio Commentary with Martin Scorsese AC3 from the laserdisc
  
• English, French, German and Spanish Subtitles
  
• Theatrical Trailer
  
• Storyboards
  
• Production Photos
  
• A Chorus Of Isolation
  
• Martin Scorsese Filmography
  

When Death Sentence was released on DVD there were two versions, Unrated and R Rated. The blu ray release unfortunately only contains the R Rated cut. Just to clarify there is an unrated released on blu in France and possibly other places, but it uses Upscaled SD footage as opposed to true HD footage. This project is a full HD restoration of the Unrated cut.

The main source of the video is the German Concorde Blu Ray. This seems to be the best blu ray out there as it is 1080P and has DTS HD audio (only High Resolution for English not Master Audio) but it's better than Dolby Digital like the UK disc. The French disc seems to have DTS HD Master Audio but I don't have this and I do wonder what real world difference it will make.

The source of the unrated scenes is a webrip from Amazon Germany, 1080p with German AC3 and English AC3 640 kbps.

The blu ray was used where possible, unrated scenes have been cut in, in some places just the unrated audio was used. To my ears the audio matched up quite well, I had to boost the volume in one of the unrated segments. The English and German audio were both exported and encoded as 5.1 DTS-HD MA.

Details of what is extra can be found here:

https://www.movie-censorship.com/report.php?ID=4695

• BD25 with menus, pop up menus, background video and resume
  
• 1080P Video 2:40:1
  
• English and German 5.1 DTS-HD MA (German has subs in parts that weren't dubbed)
  
• Spanish 2.0 AC3
  
• English, French and Spanish subtitles
  
• Fox Movie Channel Presents: Making A Scene
  
• Fox Movie Channel Presents: Life After Film School With Kevin Bacon
  
• Webisodes
  
• Interviews with Kevin Bacon, Garrett Hedlund, Kelly Preston, Aisha Tyler and James Wan***
  
• B Roll***
  
• Theatrical Trailer
  

Hello everyone! I Love IMAX/Open Matte Release

There is no blu ray for this movie so the video comes from a 1080p webrip.

• BD25 with a menu, background video, pop up menu and resume function
  
• 1080P 2:40:1 taken from the webrip
  
• English 5.1 DVD DTS
  
• English, French, German and Italian 5.1 AC3
  
• Audio Commentary with Director Rod Lurie
  
• English, French, German, Spanish and Audio Commentary subtitles
  
• HBO First Look: Inside The Walls Of The Last Castle
  
• Deleted Scenes with optional Audio Commentary
  
• Theatrical Trailer
  
• Production Notes
  

Anyone have a decent copy of the original theatrical trailer?  This is the only copy I've been able to find on YouTube, but the quality is just horrible.  I've started a new YT channel to update old trailers to HD that don't have good versions, and I'd like to do this one next.  But a LITTLE better quality would go a long way toward helping me do that.  Any help would be greatly appreciated.

https://www.youtube.com/watch?v=vzYYbBU-pzU

I also need help identifying the last two pieces of music in the trailer (from 2:04 on) if anyone knows what they are.

I decided to start this thread because I always read certain claims, by codec producers and/or users, about alleged subjective transparency of lossy codecs at really low bitrates; last of them was by MPEG-H (that uses AAC) that set transparency level at 96kbps per channel - that is 8 times less than uncompressed LPCM.

Now, how can anybody find out how lossy is that codec, or any other? And, what does it mean "subjectively transparent"?

According to Wikipedia:

Quote:In data compression and psychoacoustics, transparency is the result of lossy data compression accurate enough that the compressed result is perceptually indistinguishable from the uncompressed input. In other words, transparent compression has no perceptible compression artifacts.

• listening tests - just play one after the other (possibly with an ABX method)
  
• waveforms - using Audacity, looking for difference in waveform shapes
  
• spectrum analysis - using Spek (or Audacity etc.) looking for difference in frequency and loudness
  
• audio difference - using Audacity, load first original file; then load encoded file; if stereo, divide each track in two mono tracks; invert phase in one file; playing both (one in phase, one out of phase) will lead to cancel similar sound, leaving only the difference
  

Hi All,

This was supposed to be another relatively simple webrip project. As you can see from the screenshots below whoever made the video has cropped it to 1920x816 (i.e. 2:35:1) which is the correct aspect. However when they did it they left some black bar at the top and a little bit at the bottom. I've played around, after cropping this off it changes it to 1920x775 which makes the aspect ratio approx 2:47:1. 

So I then took the exact same shot from the DVD, cropped off the matte, resized it and laid it over the shot from the webrip - there is nothing missing from the webrip - perhaps a pixel from the bottom but nothing from the top. So it's pretty much got the same amount of picture but it's in the wrong aspect ratio.

So I'm thinking whoever made it cropped it wrong, then encoded it to 1920x816 and as a result the video has been slightly squashed. So I'm thinking my next step is to crop off the bits of black, which takes it down to 1920x775, then resize it back to 1920x816 and finally matte it back to 1920x1080. That will restore the correct aspect ratio and will be blu ray compliant.

Do you follow this logic or would you go about it differently?

Thanks