how to generate vobU-ed Mpeg1?

[unixfs]

Hi,
I've been trying to generate mpeg1 dvd for a while, but whatever encoder I use, I never come to a definitive ok:

1) either ifoedit crashes when multiplexing the streams
2) or it complains that the vob doesn't contain any vobu (when I instruct to use a pre-made vob made in linux with mplex/tcmplex)


The same problem doesn't happen when I use mpeg2 video, but I prefer
Tmpg's mpeg1 (very slow and very good .

As a side note: does an mpeg1 dvd need to contain gops in the form:
IBBP BBPB BPBB PBBP BBPB ?
I ask it because if it's not necessary it's possible to use mencoder (which uses ffmpeg mpeg1 codec) that is much faster than all the others (30-45 fps) and produces good looking videos.

Thanks

[mpucoder]

I'm not familiar with those particular programs, but I do know a little about DVD ;)
Your GOP sequence is too long for a DVD, it must be limited to 18 NTSC frames, or 15 PAL frames.
Do mplex and tcmplex produce DVD compliant vobs or just system streams? A DVD vob must begin with navigation data (NAV pack, comprised of 2 private stream 2 packets). And it includes audio and subpictures. If you are encoding only video, then it should be left in elementary stream format.

There are some more restrictions, which I outlined at http://mpucoder.kewlhair.com/DVD/dvdmpeg.html

[Navellint]

hi,
if i make a dvd-compliant (PAL) stream with TMPG 2.58 then it makes a GOP like this: IBB PBB PBB PBBP (closed GOP). This is the only way Scenarist will eat the streams (m2v+mp2, not muxed mpg of course). I guess that's what you have to use for mpeg-1 as well. Never tried it though.

[unixfs]

yes!
Thanks very much, it works :)

Is it only me to have noticed more blockyness in Mpeg2 than in Mpeg1 when using BBmpeg and Tmpg?

[Navellint]

to be honest, i don't get my mpeg-2 stream REALLY optimal. Close enough though. I deinterlace (even field) my captured miniDV-avis and that looks way better than some official dvds. But when i zoom in (with Powerdvd 4) the odd/even lines are not completely making a frame.

Maybe you should try to increase the bitrate (if you didn't already do that) from 4000 to 6 or 8 Mbps. And maybe even the minimum bitrate. Go to 'other settings' -> 'video' tab -> rate control mode change to 'automatic VBR' and 'setting' to quality 100 and max bitrate to 8000. You will not get more than 70 min on a single dvdr this way. You can see an indication of the size in one of the next windows.

Does this help?

[unixfs]

I deinterlaced using the 'double' method (really impressive during preview), and
since the total length is 127 minutes, I used a max bitrate of 9800, an average of 656 but the min was at 0, a mistake.

Yet I wonder if Ifoedit has problem importing mpeg1 video, because audio and video are many minutes out of sync.

I tried to mux the same streams in a vbr system stream with Tmpgenc, and I verified that in this case the syncrony is perfect.

Any idea?

Thanks very much, you've been very helpful.

[Navellint]

as far as i'm concerned, i don't think i can help you any further on the async, as i didn't encounter sync problems yet in any way myself. And i don't intend to start with vcd ever.
BTW, I think you have to leave some bandwidth for the audio, because the max bitrate for video+audio is 10.08 Mbps in the dvd spec. Mpeg-2 video alone has a maximum bitrate of 9800 kbps.

I'm interested in what the video with the 0 min bitrate looks like though. What's wrong with it?

[unixfs]

in high motion scenes there are a lot of macroblocks,
in other cases there are often artifacts (greenish figures) and diagonal 'waving' from top-left to bottom-right

[unixfs]

Hi,

the loss of syncrony when using Mpeg1 is surely due to a bug in ifoedit, because it lists roughly 116.000 frames against the real 127.000 (or so).

Regarding tcmplex: it seems it only generates plain system streams, but
when coupled with ifogen (part of dvdauthor package) you can get a completely working (and correct) vob/ifo pair.

Hope it helps.

[Navellint]

Tried the new ifoedit (0.95) yet? Seems to me it rules!

[unixfs]

Unfortunately it's the same story: wrong number of video frames.

There seems to be the same proportion of present frames as the ratio between PAL and NTSC fps.

Hope it helps.