The 16-year odyssey it took to emulate the Pioneer LaserActive
71 comments
·September 3, 2025daeken
puilp0502
Top in my list of "insane engineering done by emulator people" is still Dolphin's ubershader; but still, I thank that there are people like the author that dedicate exorbitant time into preserving endangered medium.
bdhcuidbebe
The ubershader is cool, for sure but the idea didnt originate in Dolphin and only took them a few years to pull off, using prior art.
OP spent 16 years fighting dragons, using his hw, sw and re skills to the max.
There is no competition.
angus-prune
What a great write up of a fascinating story.
I'm constantly impressed at the writing coming out of the emulation world. I can't think of any other technical niche that produces such consistently approachable writing about such esoteric technical subjects.
I don't understand hardware, I barely program. I don't even use emulators. Yet I will always read write ups like this and from the dolphin blog and elsewhere which give me a great understanding of reverse engineering, the community nuances, and the hacks and shortcuts that made the games possible on the limited hardware available at the time.
gambiting
It's incredible, isn't it. I'm a professional C++ programmer working on games for well over a decade now, I've done some pretty complex low level stuff on playstation/Xbox but I bounced off hard from multiple attempts at writing a simple GameBoy emulator - I just don't "get it" - but I always find it fascinating when people work this kind of stuff out, I have so much respect for them.
Tor3
This: "Pioneer's cost-cutting inside the LaserDisc player caused other parts to break:"
Far far back in time when I did hi-fi repairs and similar work, Pioneer stood out with a nice look from outside, and cost-cutting low quality work inside. Not something I liked working on.
fatnoah
The very first DVD player I ever purchased was a Pioneer model with all the possible outputs, from composite to component video, 5.1 discrete audio channels, and coax + optical digital audio outs.
I purchased it somewhere in the 1996 to 1998 timeframe. When I graduated to Blu-Ray, I gave it to my mother who used it once or twice a week up until she passed away this year.
Obviously that's purely anecdotal, but that one unit was a workhorse.
jonhohle
Pioneer provided fixes to some things, but for such a niche system there is virtually no way to get them now.
A few years ago I made a support to avoid board sag - https://www.thingiverse.com/thing:5993459
These are actually a pleasure to work on, but their rarity makes everything a bit more stressful.
ilamont
> Pioneer stood out with a nice look from outside, and cost-cutting low quality work inside.
That seems to be the standard among many appliance manufacturers these days. Slick as hell on the outside, junk/buggy electronics on the inside that may not be repairable 10 years from now, either because the part is no longer made/supported, or the expertise doesn't exist. We had an LG refrigerator that failed under warranty, and the designated local repair specialist never answered the phone.
jorvi
What I really can't stand is inefficient cost-cutting.
Nvidia, Apple, Sony and Microsoft have all at one point (or maybe still do) use ridiculously cheap solder. This only saves them fractions of a cent on $300 devices. Every few years this leads to a device that will have it's solder crack from heat stress. This usually happens well outside the warranty window, and the manufacturer will swiftly give their customers the finger. Microsoft was the exception with the Red Ring of Death getting fixed outside of warranty. PS3 with the Yellow Light of Death? Sony gives you the finger. Nvidia card cooked or MacBook borked? Here's where you can buy our new model.
Another one is the proximity sensor on phones. On midrange models, these have been replaced by a "virtual proximity sensor". Saves Samsung or whoever maybe a couple of cents, seriously degrades your user experience.
There's hundreds of these things across all industries. Its a pretty clear symptom of the fact that businesses are no longer primarily interested in their customers, but rather their shareholders.
userbinator
Blame the environmental plague of RoHS regulations for the bad solder. There's a reason military/aerospace still uses leaded solder.
wildzzz
It's super cheap to copy the look of higher end equipment, materials might cost more (metal vs plastic) but that's baked into the unit cost. Actually making the thing work well requires paying for good engineers to do the upfront design work. If you can just buy a design for cheap from some Chinese whitebox firm, your initial investment in the product is very low.
realo
Your 10 years is quite generous, methink...
Try updating a 10 year old smart phone with latest version of the os as provided by its manufacturer , up to date with latest CVE patches... :)
sgarland
TIL that a. This system existed b. The author’s need for emulation is what drove ld-decode to support extraction of VBI from Laserdiscs.
I and the handful of other weirdos capturing Laserdiscs thank you!
leshokunin
“Nemesis decided to write his LaserActive emulation as a component of multi-system emualtor Ares, partially out of respect for its late creator, Near.”
This wasn’t just a very dedicated coder with an obsession.
This is someone who deeply cared and loved emulation and the community and did a monumental effort to preserve a part of culture that doesn’t get care. Much like Near did.
Legends.
us-merul
I highly recommend this video for an overview of the LaserActive: https://youtu.be/vK0rGekPOpo?si=6XRVtA0FTRGo5sYH
Until this emulator, there are 15 games that were only playable on the physical device, never released elsewhere.
qingcharles
I always wanted a Mega LD setup. Were any of the (exclusive) games any good, though? So many of them were just Mega CD ports.
us-merul
I really don’t know! The author of the video I linked to describes one game as having full-motion video 3D environments, unlike many games on the Sega CD that were just FMVs without real gameplay. That would be funny if the best games in this genre (if you can call it that) are stuck on the LaserActive.
sandos
I never knew laserdisc was analog! Wow.
mistyvales
LD's could also have digital PCM audio tracks in addition to the analog tracks. Some of them later on had Dolby Digital 5.1 as well as some rare discs with DTS.
Look into Hi-Vision as well, which was HD LaserDisc back in the 90s in Japan. Muse was used to broadcast really high def signals for the time.
I have a player that can play both sides without having to get up and flip - CLD-D703
MBCook
Yeah that was the big difference between it and DVDs.
LDs are just the NTSC signal on the disc, the same way a CD is just raw audio on a disc (wrong! See replies). That means no compression. And given they didn’t have the higher density discs we got with DVDs they had to be the size of LPs and flipped mid movie.
DVDs were digital so the video could be compressed.
Except LDs aren’t like CDs, it’s sort of the other way around! Laserdisc came out 5 years before audio CDs. That blew my mind when I first heard it. Came out in ‘78.
apaprocki
Dual-layer DVDs didn’t come out until later. Long movies on single-layer (or those whose producers were too lazy to optimize compression or use dual-layer) DVD had to be flipped mid-movie as well.
epcoa
Mass produced dual layer DVDs came out early on around late 1997 (maybe confusing with DVD recordable?), it’s not like the spec changed. There were some low cost distributors that couldn’t afford the equipment but the majors were stamping early on.
Besides unlike the one hour max on an LD, a 120 minute movie will fit on a single side single layer, so most early movie releases would fit on a single side single layer (the quality did suffer).
More commonly in the early days the dual side was to provide a pan and scan and letterbox option or extras.
There are so called “flippers”, but they weren’t that common.
An LD is 1 hour max so you are almost always flipping for any feature length.
dylan604
DVD-5 single layer, single side
DVD-10 single layer, double side
DVD-9 dual layer, single side
DVD-18 dual layer, double side
With the dual layer discs, the first layer had to be larger than the second layer. There was a slight pause when switching layers, and care was taken to place the layer break at a spot to hide that pause as much as possible. At least on the discs where the author took pride in work unlike the YT decisions on when/where to place ads. Although, I've seen some really poorly placed layer breaks too.
goosedragons
I don't think they came out later. They existed in the spec from the beginning and some very early long movies were a single disc (e.g., Titanic). Some movies still needed flipping or two discs, like Gone with the Wind but it's just too long.
Foobar8568
I totally forgot flipping DVD for some movies or series, I can't recall now. Damn.
mmmlinux
CDs are still digital though. Its more like how records are just analog audio.
MBCook
I was just looking up laser disk and I never realized just how analog they were.
I always thought that they recorded the video signal the same way CDs did, in a series of bits.
I had no idea the length of the pits on the disk actually corresponded to the wave form. They’re not digital in any way shape or form.
Amazing. Thanks!
qingcharles
Yeah, the earliest ones were basically just a wear-resistant higher quality version of VHS/Beta. I had this 1982 top-loader model as a kid:
https://www.radios-tv.co.uk/1982-philips-vlp600-laservision-...
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jonah-archive
This is a really great read. I was briefly obsessed with laserdiscs in the mid-aughts and went as far as swapping the EFM decoder chip on a Pioneer player with something that could pull the digital audio signal out (details are a little fuzzy at this point). I wanted to figure out a way to extract the video data and it seemed so potentially possible but, as is clear, far from simple and far beyond my abilities at the time. Incredible to see that things have finally progressed to the point where one can fully capture the disc data and emulate these things.
nathan_douglas
Super cool. I really admire the diligence it takes to commit to a reverse-engineering project on obscure hardware like this, and see it through. It's tough enough just reverse-engineering software, but hardware with the constant threat of failing capacitors, a bad connection nuking a chip, etc, even aside from the technical challenges of just figuring out how to read information... bravo.
Podrod
I'm a bit of a Sega fan boy but never heard of the Mega LD before now! What a weird and fascinating bit of video gaming history, and a good read too.
Kudos to Nemesis for his hard work in preserving a bit of niche history.
jeffbee
LaserDisc was a seriously impressive technology, or at least it impressed me as a kid. My school had the (vanishingly rare) Apple Visual Almanac and some other educational LD titles that controlled the player from HyperCard. You could use a LaserActive with the Computer Interface PAC for this purpose, or you could use several other devices because there was an industry-standard serial command protocol. The Visual Almanac came with a book, floppies, a CD-ROM disc, and the LD discs, all of which were required, so it was probably the pinnacle of "multimedia" taken literally.
ethagnawl
Wow! That is very cool. I'd love to see a more detailed write up or video about that system. I really miss that era of multimedia. So much of it seems hokey and awkward in retrospect but I feel like there are lots of unfinished thoughts and experiments in that realm that are only starting to be revisited now in the AR/VR/experiential context.
I thought my elementary school was pretty baller (it wasn't -- especially in comparison!) because its library had an LD player which got pulled out once or a year to show the same space race video -- complete with frame indexing and crystal clear frames on pause. Until I bought one for myself in the 2010s, that was only one of two times I saw LD players in the wild.
iJohnDoe
Loved the LaserDisc era. Still have a huge collection. Watching the Abyss for the first time with all the extras was amazing.
My player eventually wouldn’t take the discs. Would go in the player and pop back out. A few tries would work for a while and then it eventually wouldn’t take any disc.
HD DVD was really cool. Even today, putting in a movie like Harry Potter on HD DVD really catches people off-guard on how amazing it looks. Never got that reaction from Blu-ray.
Wow. This may be one of the most intense reverse-engineering (and honestly, engineering) efforts I've ever seen for an emulator project before. Capturing the raw LD image to this degree, being able to play it in reverse, etc -- absolutely brilliant. Truly fantastic work.