Hi guys,

This probably isn't a big deal but I'm wondering for the purposes of a very very precise sync I'm currently doing (to the level of individual audio samples). I figure if I'm being this accurate I may as well get this bit right. Apologies for the number of calculations here, but it's probably necessary to explain precisely why I'm asking what I'm asking; if you want to cut to the chase and see what the question actually is, I've highlighted it below in bold. Explanation follows from here...

I'm taking an audio stream containing 362,602,496 audio samples at 48 kHz, adding 18,018 samples to sync, and combining it with a custom video stream containing 181393 frames of video. To compare the video length to the audio length very precisely, this number of video frames is equivalent to 181393 / (24000/1001) x 48000 = 363,148,786 audio samples. This means that the custom video outlasts the synced audio by 363,148,786 - (362,602,496 + 18,018) = 528,272‬ samples, or rather 528,272 / 48000 = 11.005666... seconds.

The audio is from a different video file which contains 181121 frames (equiv. 181121 / (24000/1001) x 48000 = 362,604,242 audio samples). As it appeared there, the audio lasts almost as long as the video, such that there is audio playing during almost every video frame although not all the way through to the end of the last frame (it's a few audio frames short). More precisely, the difference is 362,604,242 - 362,602,496 = 1746 samples, or rather 1746 / 48000 = 0.036375‬ seconds (36.375 ms). The duration of one video frame is 1 / (24000/1001) = ‭0.041708333... seconds = 41.708... ms, so the audo stream is still active until the second-to-last video frame, although in practice it's already fallen silent a few seconds before that.

Here's the question, then:

Is there any benefit to adding silence to the end of an audio bitstream in order to more closely match the duration of the video stream it's muxed to, for the purposes of Blu-ray Disc compliance?

If not, I'll just leave it so that the audio track fades to silence then ends shortly after that, then the video (hopefully) will continue playing for another 11 seconds after that. However, I'm wondering if this might cause some software or hardware players to freak out and possibly stop the video once the audio ends; I know some players will do this if the tracks are the other way around (with the video shorter than the audio) but I'm guessing that the video is always prioritised so it may not matter when it's this way round. If it is an issue though, I'll add silence to the end of the audio as follows...

363,148,786 - (362,602,496 + 18,018) = 528272 samples, but I'm encoding with DTS-HD MA which contains a DTS core with 512 samples per frame and 363148786 is not divisible by 512 (363,148,786 / 512 = 709,274.972... audio frames) so I'd round down the audio stream to 709,274 x 512 = 363,148,288‬ samples. This would make the discrepancy only 363,148,786 - 363,148,288‬ = 498 audio samples, or in real terms, 498 / 48000 x 1000 = 10.375 ms. That's almost identical to the difference between the original audio and video durations on the source I took the audio from, which may not necessarily be coincidental!

EDIT: Mostly inconsequential but just in case anybody notices and thinks I missed it... I realise that if I just leave the audio as is without adding silence to the end, it's 362,620,514 which isn't divisible by 512 (362,620,514 / 512 = 708,243.19140...). There are two simple solutions to that: either encode it as is and the DTS encoder rounds it up to the nearest whole 512-sample frame, or add samples before encoding to achieve the exact same result. Either way, it'd have 708,244 x 512 = 362,620,928‬ samples in the audio if I don't add loads more to the end so that it more closely matches the number of video frames.

I am currently trying to compare the settings of MBit+ on Izotope RX.
My original track is a DTS Cinema Track 16 bits / 44100 Hz, which I slowed down to 44056 Hz, and resampled to 48000.
This generated a 32 bits float track that I need to reduce.

When I zoom in on the audio spectrum, I notice that there is no difference when I truncate to 24 or 20 bits (visually and listening).

When I truncate to 16, I see a difference in the audio spectrum (but I can't hear it).

Your Opinions, or your preferences ?
Dither to 16, or truncate to 24?

Ok first off the video source for this project is from the Hong Kong Blu Ray, which is from an upscaled master. There is no HD print, so the image is far from perfect and is soft, but overall I still found it very watchable. The print suffered from dust and dirt so I've removed some of this. The audio has mainly been adjusted losslessly using delaycut, with the exception of the tracks from the German DVD as they needed the speed adjusting.

• BD25 with animated menus, background video, pop up menus and resume function
• Video taken from Hong Kong Blu Ray with dirt and dust removal
• Cantonese 2.0 Mono AC3 (192 kbps) taken from the Dragon Dynasty DVD
• Cantonese 5.1 AC3 (448 kbps) taken from the Dragon Dynasty DVD
• Mandarin 5.1 AC3 (640 kbps) taken from the HK Blu Ray
• English 2.0 AC3 (384 kbps) taken from the German DVD
• English 5.1 AC3 (448 kbps) taken from the Dragon Dynasty DVD
• German 1.0 AC3 (256 kbps) taken from the German DVD
• Audio Commentary by HK Cinema Expert Bey Logan taken from the Dragon Dynasty DVD
• Audio Commentary by star Cynthia Rothrock taken from the Laserdisc
• English (based on the Dragon Dynasty translation), French and Spanish Subtitles
• Interview with Yuen Biao (English subtitles)
• Interview with Cynthia Rothrock
• Interview with Peter Cunningham
• Theatrical Trailer
• Alternate Ending

PM me for the links, contributing/long term members only please. Contributing means active members of the forum who post and/or make their own projects.

High Resolution cover and disc art available from @Pineapples101 Here.











Just to clarify this is a project that I have made for myself which I am choosing to share. If you don't like the project, if you think it should have been done differently then feel free to keep that to yourself and consider doing your own project.

I watched a restoration of RAIDERS OF THE LOST ARK last night which included audio that I believe was taken from a 1992 LaserDisc PCM rip. For the most part it sounded good, however there are at least 2 film frames' worth of audio missing, and I believe it might actually be as much as 4 frames' worth in total.

The most obvious issue is at a point a few minutes before the 1 hour mark where the audio just drops out completely for 4190 samples of silence (88 milliseconds, just over 2 video frames at this 24000/1001 frame rate). This is after Indy says "that's it" and it cuts to a different shot:




The waveform looks like this in the 48 kHz upsampled LaserDisc track:




I don't know where the reel changes are in this film but it wouldn't surprise me if this was one of them and 2 frames were missing from whatever audio source they had as a result, but they recovered those 2 frames for the LaserDisc video and there was a mismatch. Pure conjecture though, of course. Having said that, I don't think this is a reel change since there aren't any cue marks on nearby frames at least on the litemakr scan I have.

Based on what limited info I have about it, I think the audio shown above is sourced from the 1992 US release LV 1376-WS. Does anybody happen to have access to any other LaserDisc audio sources for Raiders of the Lost Ark that may not have this section missing, either to use for patching, or as a complete replacement? I can patch it with a 35mm optical source if not, but it would probably sound smoother if I used a more similar source.

I recently found the last few DVDs I still own and wondered if they are of any interest to anyone here for a project. If so, I can rip them for you.

Links to the relevant DVDcompare versions.

Hero

House of Flying Daggers

Die Hard

Die Hard 2

Die Hard 3

If anyone wants a copy just let me know and I'll sort them out.

PS: What's the best way to rip DVDs these days?

This is not a particularly sophisticated project, and indeed although it's watchable I'm not necessarily finished with it. It was basically my first shot at mucking about with AviSynth (with some advice from this forum, actually) because I couldn't see a better way of doing it.

This is the 1997 featurette ANATOMY OF A DEWBACK, about the process of doing ungodly "Special Edition" CGI modifications to the "look sir, droids" sequence in STAR WARS (1977). It was originally released in five very short (~5 min) "episodes" exclusively on the official Star Wars website (and yeah, this was 1997 so it was a really really awful 240p, 24fps RealPlayer stream) and although later released in its entirety on Blu-ray in both 2011 and 2020, they screwed it up pretty badly both times, which annoyed me enough to try to fix it up a bit.

The original 1997 web video is long since deleted, but I kept a recorded copy of the files and recently dug them out to have a look. The video appears to be 320 x 240 pixels (4:3) but this includes black letterboxing; without the letterboxing it’s more like 320 x 192 px, which is a somewhat unusual aspect ratio of 5:3. Although this is the native aspect ratio of 16 mm film, this featurette seems to have been shot on video so it’s probably more significant to note that 5:3 was used in some countries as an early “widescreen” format for a while, presumably as a compromise between theatrical 1.85:1 and 1.33:1 (a.k.a. 4:3) home video. This original version looks something like this, if you crop off the letterboxing from the top and bottom:



On the 2011 Blu-ray, the featurette was for some reason encoded to display as (almost) 5:3 “widescreen” on a 4:3 television screen. The trouble is, even in 2011, those were a dying breed, and definitely aren’t anywhere near as prevalent in 2020. The result of this is that the vast majority of people will watch this on a 16:9 screen, but the “widescreen” image will not even come close to filling the display on account of being restricted by the 4:3 box. The actual image is a very rough looking 700 x 430 or so pixels, inside a 720 x 540 pixel 4:3 frame. It’s “open matte” to some degree as it hasn’t been framed correctly for this release, but it’s also skewed toward one side, with the left side not cropped enough and the right side slightly over-cropped compared to the old web video. It also appears to have been slightly squashed horizontally. That one looks like this:



The 2020 Blu-ray is different again, with the image being about 720 x 440 but this time it’s been cropped much more noticeably on the right-hand side than the 2011 transfer was. As a result, it can’t be restored back to an accurate representation of the original framing, and to be honest, it looks like crap overall when compared to the 2011 version. It’s also noticeably stretched horizontally, from less than 700 px (I’m guessing 640 px) to 720 px:



Since the least cropped (and least aliased) reasonably modern source seems to be the 2011 disc, I cropped and upscaled that (without sharpening the hell out of it) to fill a 16:9 screen, in order to ditch the letterboxing and attempt to fix (as far as possible) the slightly deformed aspect ratio. Since a bit had been cut off the right hand side, I also cropped a little bit off the left to recentre the image, adding equal borders on the left and right to fill a 16:9 screen and upscaling to 720p. Since the source was interlaced, standard definition NTSC, I deinterlaced it with QTGMC. Do not expect this to look like HD footage, because it’s not, and it shows… but it’s a heck of a lot better than the 56k web streaming version and is framed better than either of the official Blu-ray Disc versions as well.

Here’s the 1997 web version with the letterboxing removed, then the remaining frame upscaled to fill a 5:3 frame inside a full-screen 16:9 display, to show what the ideal framing would look like:



Then the same thing but cropped in slightly on all sides to better match the available picture information in the 2011 Blu-ray version (since the 2011 BD version is slightly cropped on the right as well, I cropped in on all sides to restore the original 5:3 aspect ratio):



This was used to work out the most accurate crop and size adjustments for the 2011 video.

The end result is a precisely 5:3 frame with black bars at the sides to fill a 16:9 screen at 720p, instead of a tiny 5:3 frame inside a 4:3 box in the middle (which would have been great when we all used 4:3 TVs but is extremely inconvenient nowadays). It could most definitely look better and the image is still not 100% accurately re-warped to match the exact aspect ratio of the web vid but then it's entirely possible that was wrong in the first place anyway; if I knew more about upscaling and had access to tools like AI sharpening (rather than simple AviSynth filters that create ringing artefacts worse than what you already see below) then perhaps I could achieve better results. I did try just about every resizing filter I could find any info on, and this appeared to be the one that produced the least artefacts. I've also left it in the original BT.601 NTSC colour space rather than outputting BT.709, which may or may not be wise (open to suggestions, would be easy to re-render out BT.709 instead).

Anyway, here's how it ended up after the above:



THIS IS A FAN-MADE PRESERVATION OF BONUS CONTENT FOR A FILM I CARE DEEPLY ABOUT (AND HAVE LEGITIMATELY PURCHASED MANY COPIES OF). I DO NOT ENCOURAGE PIRACY. If you are downloading this, then I consider it a prerequisite that you already own an officially released version of what you are downloading. If you don't, then you should purchase a copy before downloading, as long as that item remains available for purchase. If it has gone out of print, then perhaps a digital copy is available. If no physical or digital copy is available to purchase and you don't already own one, then you are downloading at your own discretion. At time of writing, both the 2011 and 2020 box sets containing this video are still available for purchase.

Furthermore, THE CONTENTS OF THIS DOWNLOAD MUST NOT BE PARTIALLY OR FULLY REPRODUCED FOR PROFIT UNDER ANY CIRCUMSTANCES WHATSOEVER.

Thank you for understanding.

Sorry for the noob question but I'm not 100% sure what Cinema DTS actually is and it seems to be regarded as the best type of soundtrack.

I assume it's the DTS soundtrack used in the cinema but then that makes me wonder why it isn't used for the home release of movies.

And then I wonder how you guys come about these tracks.

Thanks in advance.

Here Is the Dolby Surround AC3 2.0 Mix of Mission Impossible (1996) ripped from the Special Collector's Edition DVD. 

https://www.mediafire.com/file/aso5p7wtx...x.ac3/file

The delay for this is 1700ms. This syncs perfectly with the remastered 4K UHD BD , so enjoy!

Hello!
Thanks to spoRv, I now have two perfectly in sync sources that I can overlay. I did some manual editing of one to make sure it was frame perfect, but even though I did that it's a few frames out of sync.



Is the fact that I'm using VirtualDub2 instead of AviSynth an issue? I couldn't get it to run in Avisynth 2.6 or AviSynth+. When this plugin works it works excellent! Hopefully I can get this finished and I can start to contribute instead of just asking questions.. 
Any help is appreciated. Thanks

So I was poking around out of boredom and scrolling through a 35mm print inventory that was posted on another forum–where I've been more recently been able to make scanning efforts for some of the listed titles–when I noticed something that caught my eye.

Apparently within that collection, there's an Italian 35mm print of Dario Argento's Inferno with a 4-Track Stereo Mix.