Not sure what ACM refers to but MVE movies were used in Descent2 and are pretty well understood, e.g. https://wiki.multimedia.cx/index.php/Interplay_MVE . I think there were some additions to ffmpeg a few years ago that added some of the unknown opcodes.

ACM's an audio codec Interplay had used throughout since around Starfleet Academy and FallOut, and that was also involved with their second-party devs

ACM is such a unfortunate lossy compression that conversion to any other lossy format will be immediately noticeable. (atleast to my ears)

The MVE's don't seem to suffer as much being converted to H264 using libx264 on the "veryslow" preset. Considering every major hardware vendor supports H264 in hardware that's probably a good thing to turn the videos into. Though, I've seen projects insist on using VP8 or VP9 instead; of which only VP8 is supported in hardware on my platform DESPITE Intel insisting Skylake can decode VP9.

The Official Reddit discussion, for those who are interested....

https://www.reddit.com/r/gamedev/comments/1c5 … _for_descent_3/

DracoNihil wrote on 2024-04-16, 16:08:

Considering every major hardware vendor supports H264 in hardware that's probably a good thing to turn the videos into.

Why are we turning the videos "into" anything? If someone's making a source port it would need to handle the original data files, i.e. it would need to play MVEs. Nobody is going to want to pre-process game files with third-party tools beforehand.

if someone wants to make a remake/remaster than enhancing videos is an option
open source means we can provide videos

robertmo3 wrote on 2024-04-16, 19:24:

if someone wants to make a remake/remaster than enhancing videos is an option
open source means we can provide videos

It's not an option to rip off copyright game assets.

jmarsh wrote on 2024-04-16, 19:01:

Why are we turning the videos "into" anything? If someone's making a source port it would need to handle the original data files, i.e. it would need to play MVEs. Nobody is going to want to pre-process game files with third-party tools beforehand.

Well tell that to the wz2100.net people who converted all the videos into Ogg Theora rather than implement a way to playback the original files in the source code release...

I don't know if someone's going to go after somebody because somebody wrote a third party method of decoding MVE.

also before anyone assumes (because there ARE some), no opend3cent from me etc. I don't even know about any D3 content pipelines (should anyone start one, but should be less restrictive/hard bound than D1/2 was). I don't even like descent 3

DracoNihil wrote on 2024-04-17, 03:06:

I don't know if someone's going to go after somebody because somebody wrote a third party method of decoding MVE.

Unless Interplay has managed to patent the format they can't. More practically decoders have been included in ffmpeg for literally decades (also ScummVM more recently) without any legal challenges, meaning they haven't bothered to protect their IP (this is why the MPEG-LA tends to be so strict about enforcing licensing).
Point seems moot anyway, apparently an ex-interplay employee has offered up some code for it. Although if it were up to me I'd code it from scratch regardless, it's really not a lot of work given the available documentation.

Back in 2002 Volition released the source code for FreeSpace 2 engine after getting bought by THQ and the FreeSpace license was left with Interplay, the source code project that jumped on it initially left MVE support out and just offered re-encoded movie files in ogg format for download. No idea how legal that was but no one evidently cared if it was illegal. Not that it's a good idea to take that risk if you can help it of course. They later somehow added MVE support back so you could just copy the movie files from your discs/digital copies, that hasn't made any lawyers start barking either.

I wonder does the FreeSpace 2 engine and Descent 3 engine share any parts of them, maybe some of the things FS2 SCP has made over the years could be used with D3 too.

Currently there's license picking trouble.. The MIT license mentioned earlier was an oversight

leileilol wrote on 2024-04-19, 05:35:

Currently there's license picking trouble.. The MIT license mentioned earlier was an oversight

That is no longer the case:

https://github.com/DescentDevelopers/Descent3 … ob/main/LICENSE

GPLv3