Duck TrueMotion help

Greetings all.

I was interested in translating a videogame that came out for Saturn known as D: The Game.
While i was trying to figure it out, since it would be my first work on translating something that required tweaking and some knowledge (rather than just edit some files and translate them), i was interested in also updating the visuals to the videos so that it would be in higher resolution.

So, i've looked at the video files and even though the version i'm currently trying to adjust is the DOS version, it uses the same encode as the Saturn, a.k.a. Duck TrueMotion 1 (.duk).

I've read some discussions here regarding it but i found out it was impossible at the moment to re-convert the video-file from let's say MP3 back to .MOV + .duk encode.

Has anyone had any luck regarding the encoder, and if so, is it possible to convert back into .duk file and then make it work in-game as a substitution to the original video?
Otherwise, to reuse the .duk files from certain games if the format interests you, I believe you also need to recode the executable for the resolution. It's really not easy.

I did some tests, for example with "Pandemonium," but I didn't succeed. The videos wouldn't launch, and the game crashed.

It seems I wanted to use a higher resolution video format for the startup logo in the same game, but I couldn't. It "should have" worked... The CPK codec is nicer and allows for more flexibility.

Otherwise, as for standard video recoding.

It's quite simple. The easiest way is to change only the audio track while leaving the video as it is, thanks to VirtualDub. It's better to use a version under Windows 95 since there are incomprehensible bugs with the videos once finished on Windows 98.
As for modifying the videos, I've always experienced a slight loss of quality. Depending on the Duck video codec and the format, sometimes it's not straightforward (Subtitling).
Hi to all. Well, duck codec not is an easy-peasy thing. It was/is a great piece of software and technology for that time. For your objective, some community user achieves to change videos as @paul_met . He in Vandal Heart changed the videos for new ones with successfully. You will need all the official codecs for that time and install in a virtual win95 machine. You can find this video tools from official Sega SDKs: SegaXtreme - Tools here the specific for duck:
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