Laserdisc porn? Was that actually a thing?

Interesting subject. Laserdisc is probably the last format anyone would think of when you mention home theater these days.

I've been contributing to a relatively new software project designed to capture the raw radio frequency signal from the laser as it reads the disc. For the nerds, the Laserdisc format used a series of pits and lands, much like a CD. However, it was not a digital format. The arrangement of pits and lands on the discs modulate an analog signal, which is picked up as RF when read by the laser. The software then reads the raw RF signal and looks for video, sound, subtitles, and other information on the disc. With a few scripts you can decode the resulting digital version of the RF signal and convert it to the original program, with very good results exceeding the best players!

This demo disc was fully played back in software, not via a capture card or very expensive MUSE player. Once it was captured, the player and disc are no longer needed to play it back.

I disagree actually. While DVD used the superior YCbCr encoding format, Laserdiscs were not digitally sampled or compressed. Depending on the color space, red was often (if not all the time) sampled at a lower resolution that the rest of the picture content, causing blockiness in areas of high color saturation. This is also not including digital MPEG-2 compression. Both artifacts are present on all DVDs.

Laserdiscs have flaws such as disc rot which deteriorates the signal to noise ratio at times, but it was the only consumer analog format that stored the video in full 6MHz composite bandwidth. It was basically better than broadcast, as broadcast had AM modulated noise in the picture and other distortions from over the air and cable transmissions. Not to mention most Laserdiscs use analog FM for the sound, which is not digitally compressed in contrast to AC-3 compressed audio for DVD.

Hopefully I can get my raw disc capture solution hammered out soon. I'm basically hacking a standard video capture card so it will digitally sample the signal at about a 3.85 to 1 ratio. I'll probably share a successful decode and playback of something once I get a clean enough signal from the laser in my player.

I have a nice wideband amplifier, but it doesn't work with my player's RF circuit. Someone else with the same amplifier has a similar issue. This amplifier is optimized for photodiodes, so I'll have to try and locate/tap the output directly from the optical pickup. Now I'm poring over service manuals to try and solve that riddle.

"Ripped" discs.

Yeah just pulling your leg, hence the wink.

Here's a neat video on that Pioneer player:

Nah it's fine, sarcasm doesn't translate well.

Is anyone else thinking about LaserDisc preservation? As the discs rot and more obscure stuff is lost, it's gone forever unless someone captures them and puts the captures up on archive.org or something. For example, I heard the Toy Story LaserDisc has an alternate version of a Pixar short that is more adult oriented.

I forgot about this thread. Here's my Terminator 2 test result using the raw RF signal software decoding/displaying method. This is jacking directly into the laser head pickup and doing all the heavy lifting with a Linux software program to pull out the video, audio, and other digital information stored on the disc. Unparalleled picture and sound quality!

https://www.mediafire.com/file/fgsnks1pxwotarb/terminatortest.mp4/file
v2sKu4H (resized).png4QEkZk5 (resized).png03Fmhnu (resized).png

Yeah it's definitely a new way to preserve LaserDiscs and VHS tapes. I've modified my VCR in a similar fashion. For deinterlacing I used to use Yadif with Avidemux but have found out that QTGMC with Avisynth works a lot better.

Just to be clear though, this method requires significant hardware and electronics knowledge and soldering skills. And it also requires a bit of Linux know how involving the terminal. There's this thread for Laserdisc:

https://forum.lddb.com/viewtopic.php?f=32&t=2671

And this one for VHS:

https://forum.videohelp.com/threads/394168-Current-status-of-ld-decode-vhs-decode-%28true-backup-of-RF-signals%29

I actually saw a CED disc at Goodwill several years ago. I had no clue what it was. Assuming I will never see another one.