NTSC = Analog
DVB = Digital Video Broadcast Mpeg 2 codec.
DVB 8psk = Digital Video Broadcast, Mpeg 4, 8PSK codec. (more efficient compression)
DVB 4.2.2 = Digital Video Broadcast, Mpeg 2, 4:2:2 codec (the color is encoded different)
MPEG 1.5 = A half breed of Mpeg 1 and 2. (used by Direct TV)
Part of the confusion {for me} is that MPEG is both involved in the specs for the signals that carry the video AND for the video itself. For example, the DVB thing above is transmitted in a mode described by some MPEG2 specs, however I don't think it is related to any MPEG2 codec. I think {very likely wrong} that the MPEG-2 spec contains the fundamentals for not only DVB, but also DCII and DSS transmission, but is MOST related to the actual video carried in any of the MUXes involved in any of these modes of transmission, moreso than the MUX itself.
Also a codec is usually a program that can decode the A/V streams. Ie there are codecs that will decode mpeg2 or mpeg4 video, but I don't think I've seen a codec for DVB or DSS or DCII. Ie the CODECs are for the A/V carried by the upper level mode. There can be different flavors of codecs for each kind of video, but the actual DVB format doesn't care at all about codecs, or even if the video in the mux is MPEG2 or MPEG4 or some other format.
Also, re to DVB 8PSK, I think that it is confusing to relate it to MPEG4. Some people relate MPEG4 to DVB-S2, and I think that is misleading also, even though they came out at about the same time. I'd bet that most of what has been sent in DVB 8PSK is probably MPEG-2 video, although I've never had a receiver that would do this mode... Actually, I'm assuming here that DVB 8PSK refers to TRELLIS 8PSK, but perhaps I'm wrong on this assumption too. Of the various 8PSK modes, there is TRELLIS, DVB-S2 8PSK, and Turbo 8PSK, and it was always my impression that DVB 8PSK was the Trellis variety. Generally, if you see DVB by itself, it refers to QPSK modulation, unless it says 8PSK. But I think that MPEG4 really mostly refers to the video mode, not to the overall package that you'd find it transmitted in. You could find MPEG4 video in any of the digital packages.
Anyway, this whole thing is really confused because the various MPEG specs do a lot of different things, and they can be mixed in a variety of ways.
Also.... Re to
4DTV is Digicipher 2 which is Mpeg 2 with GI's own proprietary changes to the Mpeg 2 standard.
I think that this is still unclear. 4DTV is the name of a receiver model, not really related to the transmission modes. It is a receiver that can do analog ITC, VCII subscriptions (analog video digital audio), and DCII (digital A/V). So I don't think it is right to say that 4DTV "IS" DCII, it's just one receiver capable of receiving DCII signals. Also, as mentioned above, although DCII is sent in an MPEG spec, and most of the video is in MPEG2 format, I don't think that there is any reason why MPEG4 couldn't be sent via DCII, as the DCII is really just the carrier, and just like you can put any kind of stream in DVB or DVB-S2 (ie you can have data, MPEG2 video,MPEG4 video, 4.2.0 or 4.2.2 video, various flavors of audio, etc, etc), any kind of stream can also go in a DCII signal.
I think the most important destinction about these various modes, ie NTSC, DCII, DVB, DVB-S2, DSS, are that in general, different receivers are required to do each mode.
Ie analog receivers generally do NTSC analog only.
DVB receivers won't do DVB-S2, DCII or DSS, and usually they only can play MPEG2 video, not MPEG4.
DVB-S2 receivers will generally do DVB and DVB-S2, and can generally also do MPEG2 and MPEG4 video on the mux.
DCII receivers generally won't do DVB or DSS.
DSS receivers only do DSS.
Yes, some receiver do more than one mode. 4DTV will do DCII and NTSC analog. A Genpix receiver will do DSS, DCII, DVB and Turbo 8PSK/QPSK. But in general different receivers for the different modes.
One good web page for info on most of the above is:
http://www.coolstf.com/mpeg/index.html although there is less info there about the newer DVB-S2 and 8PSK modes.