Could a Laserdisc be mastered at NTSC 60.00Hz instead of 59.94?

[BusterD]

Ah yes, that would probably work, should've thought of it myself... Thanks again!

[Chewtobacca]

Going back to the OP, can the blu ray 1080i be IVTC'd back to 23.976?

It's possible, but many of the animes at which I've looked have sections that were animated at 29.97fps/30fps. Whether that's true of this release, I don't know, but I'd be wary of performing an IVTC without checking the video stream carefully for such sections.

[zoidberg]

It's possible, but many of the animes at which I've looked have sections that were animated at 29.97fps/30fps. Whether that's true of this release, I don't know, but I'd be wary of performing an IVTC without checking the video stream carefully for such sections.

True, I forgot about that. Plus it sounds like the aim is to leave the video untouched.

[BusterD]

Going back to the OP, can the blu ray 1080i be IVTC'd back to 23.976?

It's possible, but many of the animes at which I've looked have sections that were animated at 29.97fps/30fps.  Whether that's true of this release, I don't know, but I'd be wary of performing an IVTC without checking the video stream carefully for such sections.

Hmm, I was under the impression that there were only 30fps sections in anime after it had started going digital, other than stuff like video overlays (scrolling credits, etc.) and field-based video edits (so one would need to watch out for cadence changes). So I think Devilman Lady is mostly safe in that regard.  I haven't notice any cadence losses or jaggies while watching the BDs, at any rate.

[Chewtobacca]

Hmm, I was under the impression that there were only 30fps sections in anime after it had started going digital, other than stuff like video overlays (scrolling credits, etc.) and field-based video edits (so one would need to watch out for cadence changes). So I think Devilman Lady is mostly safe in that regard.

Ah, that's good to know. I'm not familiar with Devilman Lady.

[schorman]

I can weigh in on the dabate about 44,056Hz. It is most definitely misinformation and can easily be proven false by reading through the documentation of happycube's ld-decode project.

My quote from another forum at redacted.ch:

"My point is that that info is completely bunk. There is not one disc that was ever authored that way. PAL and NTSC discs with digital audio all have stereo PCM (or DTS encoded as PCM) tracks, sampled at 44.1kHz-16bit. This 44,056 version has never been documented to exist. Wikipedia is wrong on this.

In fact, using the software LD decoder here: https://github.com/happycube/ld-decode, by happycube, the same code can be used to decode to digital audio from the raw RF signal produced by reading either an NTSC LD or a CD. In short, NTSC laser discs store the audio track in an identical way to a CD. They do not use a 44,056Hz sampling rate.

My guess is that this info is based on the original LD standards published in the 70's. PCM was typically stored on video cassettes in those days, and was recorded in a way that relied on compatibility with a black and white NTSC or PAL video system. This was before the advent of the CD, and before Sony and Philips settled on the sampling rate they would use.
Remember that while LDs predate the CD, they did not utilize digital audio until after the Redbook standard was in place, and CDs were on the market. It stands to reason that any earlier plans on how to store digital audio on LD may have been altered to match the already prevalent 44.1kHz technology. "


Further quote from HappyCube at OT.com:

https://originaltrilogy.com/topic/Unoffi...e/1#791682


Based on available knowledge, the modulated RF signal used to store the Digital Audio track of a LaserDisc is identical to that used by CDDA. They are both storing audio as 44.1kHz at 16 Bit, and can both be decoded/demodulated in the exact same manner using the same electronic circuitry or software decoder, as is done by ld-decode.