Encoding MPEG -> Laggy video?

[eSKape]

Hi guys

I've encoded (converted) a home movie from DV-AVI to MPEG (MPV) following the guide here on Doom9.org.

I used MainConcept MPEG Encoder for the encoding, and everything seemed to work fine, but the output video is a bit laggy. How come? :confused:

I've got a P4A 2.0 GHz with 512 MB RAM and a Geforce Ti4400 gfx card.
Shouldn't that be sufficient?

Best regards
Noobie-eSKape from Denmark

[CWR03]

Define "laggy." Poor framerate? Jerky playback? Audio/video desynchronization?

[eSKape]

Well, first, it's without sound (that is in a seperate ac3 file according to the doom9 guide). But it kinda .. well, yeh, jerky.. it is not every single frame that is slow, but well like ever 100ms there is a lag. Difficult to explain...

In the source, there is a lot of horizontal lines.. is that interlazing problems? And can it be fixed? It is also in the mpv file.

[jggimi]

I'm only guessing, but was this an NTSC DV? And did you happen to inadvertantly use an Inverse Telecine on the content? If the frame rate of the DV was 29.97 fps, and the frame rate of the .mpv is 23.976, then that is your problem.

Only Inverse Telecine (IVTC) content that was a film transfer to NTSC from 24fps film -- that stuff with the sprockets on the side.

Of course, this is just a guess.

[eSKape]

Is that the lagging or the interlaze-thing you are adressing?
The lines I can live with, mostly because they are on the source too, but the lagging isn't good...

I wouldn't guess on NTSC, because I'm in Denmark, Europe, and we don't use NTSC anywhere...

[jggimi]

I was trying to address what you described as "jerky" -- it was just a guess, as I stated.

Can you cut a fragment of your .m2v file and post a link on the web?

[eSKape]

I can try :) What cutter would you recommend?

[jggimi]

TMPGEnc? Cuttermaran? You pick.

[eSKape]

http://eskape.joke.dk/files/cut1.mpv (http://eskape.joke.dk/files/cut1.mpv) - There you go :)

edit: Ok, going to bed for today (and so is the server)
edit: It's up again tomorrow at about 9am GMT+1.
edit: Thanks for the help so far, looking forward to tomorrow :)

I'm trying to cut the original avi source, so you can see the difference, but I cannot find a descent program... Easy Video Splitter wont work :(

[jggimi]

for cutting avi, you can use VirtualDub or VirtualDubMod ... but only if the DV AVI was Type 2.

http://www.doom9.org/vdubmod-procedures.htm
http://www.doom9.org/virtualdub_procedures.htm

[eSKape]

Hmm.. It says this when I try to open the original source:
[!] Couldn't locate decompressor for format 'dvsd' (unknown).
VirtualDub requires a Video for Windows (VFW) compatible codec to
decompress video. DirectShow codecs, such as those used by Windows Media
Player, are not suitable. Only 'Direct stream copy' is available for this
video.
Is that because it is not a DV type 2?

[jggimi]

No, that's because you don't have a VfW DV codec installed. See Q 5 and Q 9 in the DV FAQ (http://forum.doom9.org/showthread.php?t=30495).

[jggimi]

I've taken a look at your mpv fragment. I see two things:

I see interlaced video, of course, as DV is interlaced. This shouldn't matter, if you're going to take this to DVD format for display on interlaced devices. If you intend this content to be played on PCs, you'll want to deinterlace.

Much more troublesome: I see some duplicate frames. These are most noticeable right at the end of the fragment if you step through frame-by-frame as the people are moving and talking while drinking champagne. You'll want to step through the same scene(s) in both your .avi capture and your finished .mpv to see if both have the same duplicate frames.

If both have the problem, there was likely a problem during your DV "capture" from tape to hard drive. Dropped frames during capture are often treated as duplicates, in order to keep a/v sync.

If only the mpeg-2 has the problem, and the .avi doesn't show these duplicate frames, then there was a procedural or software problem during your AVI -> MPEG-2 encoding process.