According to the
Wikipedia, the Dreamcast drive is 12x, but it does not mention if CLV or cheating wie ith "up to" CAV.
1x being 150KB/s (1200kBit/s) [or 176KB/s Mode 2], there should be no practical limit in data rate.
On the other side, the standard VCD uses 1150kBit/s for video and 224kBit/s for audio resulting in approximately 1x speed for reading → same playing time as CDDA.
On anime the TV has an easy time upscaling in a very good looking way, but honestly life action movies look awful in that resolution, regardless of the bitrate. This is why I played around more with SVCD which can be – depending on the source material – surprisingly good for outdated MPEG-2 codec and very limited space on CD (compared to DVD).
DVD video on CD, sometimes called CDVD or Mini-DVD (not to be confused with 8cm DVDs: Mini in space) can reach full quality, but runs only about 15 minutes.
3000kBit/s and almost 400 for audio (would like to reduce the audio as well) is serious overkill. Fitting a complete normal movie of 90min on one CD is usually my goal with these kind of experiments.
My feeling tells me the Dreamcast could potentially be able to software decode MPEG-2 and an SVCD player could be in range. That would be awesome.
For the case Dreamcast doesn't like current MediaRange 100min CD-R, I got these (must be from about 2002):
Edit:
Strangely enough the results of just detecting GigaRec CD-R aren't consistent or convincing. Don't know what to make of this. Original GDs also use smaller pits (and work normally on my console -- the drive is still pretty good)
For the first test I converted a cartoon episode of 25minutes and burned it to CD-R (Rewritables are completely ignored by the Dreamcast). Looks nice, but the practical use is very limited. Fun thing to do.