Laserdisc PCM Capture Guide

[bendermac]

Update for macOS users

audacity and GarageBand are not useable for Bit-Perfect capture

So if you are running macOS Mojave or above you can only use Logic Pro X and Reaper. If you're running High Sierra, then you can also use Quicktime Pro 7 (not free)

[deleted user]

You could try Ardour too if you haven't yet, it's a free DAW. But I remember it was a bit not too user friendly.

[bendermac]

I don't call this Free: Periodically goes silent after 10 minutes.

[williarob]

Using the guide in the first post I was able to confirm a bitperfect capture by ripping a few minutes of a DTS laserdisc, capturing the audio in Reaper, and using DTS Parser to convert the .wav to .dts.

Presumably though (and I haven't tried this yet), if I were to capture the digital audio in AmarecTV or Virtualdub along side the video signal (so that they are in sync) I would only get a regular wav not a DTS wav? And if that's the case, does anybody have a recommended workflow for syncing the DTS Wav? I'm guessing the easiest way would be to capture the analog audio with the video at the same time the DTS audio is captured in Reaper, then use something like EAC3To to convert the DTS Wav into 6 mono .wav files, import them all into Premiere along with the video and analog audio, sync the tracks, make the edits (remove the side changes, etc) and then re-export the audio as 6 new mono wav files (is that even possible from Premiere? maybe with 6 separate exports and the other audio tracks muted?) and then finally use EAC3To again to encode a new .dts audio file for muxing with MKV Toolnix? Or is there a better way?

[spoRv]

... if I were to capture the digital audio in AmarecTV or Virtualdub along side the video signal (so that they are in sync) I would only get a regular wav not a DTS wav?

You will got a raw PCM wav; then on VirtualDub (or AviSynth) you can put it in sync with BD (or whatever source) using frames for sync - hence discarding or adding "blank" frames at the beginning, using the few first silent ones to fill the eventual gaps - and at the end parse the result with DTSparser.

[williarob]

... if I were to capture the digital audio in AmarecTV or Virtualdub along side the video signal (so that they are in sync) I would only get a regular wav not a DTS wav?

You will got a raw PCM wav; then on VirtualDub (or AviSynth) you can put it in sync with BD (or whatever source) using frames for sync - hence discarding or adding "blank" frames at the beginning, using the few first silent ones to fill the eventual gaps - and at the end parse the result with DTSparser.

Cool, thanks. I'll give that a try and see what happens.

[williarob]

So I tried capturing the DTS track with Virtualdub and Amarec TV and the wav file I exported via Direct Stream Copy from Virtualdub could not be parsed by DTS Parser. So I guess it's not a bitperfect capture that way.

[bendermac]

How to capture Bit-Perfect on macOS with Apple's Logic Pro X

This very straight forward. Lets begin

1. Open Audio Midi Setup (Location: Applications>Utilities)
- select Build-in Input and choose under Format: 2ch 16bit Integer 44.1kHz
I highly recommend you verify this before you capture a new LD after a reboot



2. Open Logic Pro X
- New Project > Empty Project and click Choose

- in the next popup select Audio and unter Audio Input select Input 1 + 2, then hit Create

- open Preferences and go to Audio. Select Build-In Input as your Input Device.

Jump to the Recording pane and select WAVE (BWF) for the Recording File Type. Make sure you don't check 24-Bit Recording.

- Close Preferences


3. Capture your audio

4. When your capture is finished, save your project

5. Export your audio: File > Export > Audio File as

[williarob]

I'm on Windows

I can capture bitperfect audio from the laserdisc player using Reaper. Hopefully it won't be too hard to sync that to the video.

[williarob]

Further testing reveals:

1. Editing the bitperfect DTS WAV file in Adobe Audition, and resaving (still as a 44100 16-bit Stereo WAV) remains bitperfect. DTS Parser can still parse the whole file.
2. Editing the bitperfect DTS WAV file in Adobe Premiere Pro, and resaving (still as a 44100 16-bit Stereo WAV) remains bitperfect. DTS Parser can still parse the whole file.
3. Editing the bitperfect DTS WAV file in Adobe After Effects, and resaving (still as a 44100 16-bit Stereo WAV) did not work. DTS Parser could only parse the first few seconds and then choked. Tried it twice.