I've never done a youtube video before, but that's probably the best way to sum up where things are right now, as I can show visually what's been done, the hardware involved, and what's still pending and why it's important. To try and give a 30 second summary, here's basically where things are:
1. I can rip the full 2448 bytes of effective sector data for the entire digital content of the MegaLD disks. This includes the lead-in (with the TOC), pre-gap, actual track data, and lead-out, with full subcodes. This took reverse engineering the MegaLD hardware, learning how to cartridge-boot the MegaCD platform in general (never done before), writing custom dumping software to drive it, developing read routines for full subcode data for the MegaCD (never done before), hardware mods to the MegaLD PAC in order to get at the full TOC data, developing a high-speed USB transfer option from the Mega Drive controller port to stream data to the PC, and then writing a chain of half a dozen programs to error correct it, reconcile subcode errors between multiple media sources and successive rips, and merge it all together to get a good, complete data dump. This process has been fully working for around 2 years IIRC.
2. Analog video is still a bit stuck. Originally, I believed I could use off the shelf commercial video capture hardware. This was incorrect. Nothing existed that would properly preserve the important control codes in the vblank region in full. I investigated making my own hardware capture device, and made a few attempts at this, but the data transfer requirements were a killer in terms of bandwidth, and I didn't have enough knowledge on analog signal processing to do a good enough job at it. I was still exploring this space though, and was having a good look at SDR (Software-defined radio) hardware to solve it, until the emergence of the Domesday Duplicator project (
https://www.domesday86.com). I've been following this for years, and I've built every hardware revision of it as it came out. I can now get full captures of the raw RF stream from the laserdisc. The remaining problem is the software decoding space. You'd think in 2019, software decoding NTSC video would be a solved problem. It isn't, and until ld-decode there was basically nothing out there that reasonably attempted it. The ld-decode software isn't far enough along yet to decode these disks though. The comb filtering in particular makes a lot of assumptions that don't hold true for the video on MegaLD disks, and the TBC system isn't perfect either. I've had a shot at writing my own software de-muxing of Laserdisc RF, and my own software decoding of NTSC video. Both of them work to some degree, but both of them have their own different problems to the ld-decode software currently. A few months ago Chad Page was on a bit of a roll with ld-decode, and I was hitting a bit of a wall, so I shelved my efforts for awhile to leave him to run with it, and see where things ended up. I'm re-evaluating that now, seeing where he's up to, and looking at the problems I was having again to see if I can solve them.
In a nutshell, things are close, but not done yet. The amount of effort that has gone into this is truly insane. If I ever thought I'd have to learn how to demux an RF signal and decode NTSC video in order to achieve the outcomes of this project, I never would have even started it. As I post this though, I've got a ripping process running in my garage to re-dump the disks using the latest techniques and hardware. I'm still holding out hope to get some good decodes of the video happening in the next 6-12 months. If that doesn't occur, I'll most likely shove the terabytes (literally) of raw RF dumps on some file store just to get something out there in the interim. Those raw RF files will need to be preserved regardless, as the software decoding space will continue to evolve and you'll want to be able to re-run it from the source, but for actual emulation, the goal is a full digital data stream in a simple form (which I have), alongside a full analog video/audio stream in a simple video container (which I currently have as RF, but can't reliably decode to actual video yet).