Jitter when converting with AutoGK

[TvMind]

Hi folks,

I have been recording and burning to DVD, from my beloved Pioneer DVR-550-H-K, years of classic tv episodes from C-band (satellite) television, and burn about 9 episodes to one DVD5 disc (avg 22 mins / episode) in MN13 rec. speed (a good compromise I found, without losing much detail.). The source is impeccable, as it is the uplink from the NOC (Network Operation Center). Now the problem.

I have boxes of 100 disc cake boxes of these glorious shows and have been trying to compress them to I can burn say one season onto one DVD9 as one of my favourite posters on Usenet has done (fixed size of 175MB). Now I have done so with AutoGk but when I watch them on the stand alone DVD player (ESS mode), many models in fact, during a fast movement there is an annoying blurring/jitter. No matter what setting I choose and which codec (Although Divx seems better) I get this annoying stream, or jumpy smear. I haven't touched the advanced settings, but IIRC I have experimented with those as well. Of course on the pc with VLC all's fine.

I haven't had any success contacting the author I mentioned for tips on how he captured and converted his recordings. I did look at his codec info and he uses Divx not Xvid, which almost did the trick, but also is problematic. This is very frustrating , having spent years painstakingly recording , editing, and burning to DVD these classics, only to have them sitting in cake boxes. I thought that one day I will buy a Blu-Ray burner and put tons on one disc - don't even know if this is possible. The point is I want to preserve the good quality and not settle for crappy compression artifacts. Each VOB , episode is just under 500 MB, and would like to get that down to half, or 250 MB, even 175MB, but without significant loss of detail. The other issue is AutoGK audio is too loud (clips) when selecting mp3, so I stick with original audio AC3 ( I have to use mp3gain to boost the low volume of the AC-3 decoder, Technics SH-AC300).

At this point I will continue to back up the DVR to DVD's, and will always do this. I have no interest in using Videoredo, although I have a licensed copy, because I love being able to do all this from the comfort of my couch. I don't know what else to add. Maybe I can upload a clip somewhere if that helps. But I have the feeling this is a common complaint from perusing the video forums.
I will be quiet now and listen anxiously for your responses if any.

Thanks

[Baldrick]

Upload a short sample from the dvd vob source.

[TvMind]

Hi Baldrick thanks for chiming in. Here's a small clip saved from VidoRedoPlus.

This is an analog recording to the DVR, with the sharpness on the receiver set to "sharp" (I realize soft is better, but I don't want to lose too much detail on the DVD's, but for compression soft is better, right ?).

I also can upload a direct digital sample from another receiver that records transport stream of the entire transponder if that will help.

[nic2k4]

... one of my favourite posters on Usenet has done (fixed size of 175MB). Now I have done so with AutoGk but when I watch them on the stand alone DVD player (ESS mode), many models in fact, during a fast movement there is an annoying blurring/jitter. No matter what setting I choose and which codec (Although Divx seems better) I get this annoying stream, or jumpy smear.

That has to do with the low bitrate you might end up using to maintain that fixed size. Old shows tend to be grainy, that will eat up part of the bandwidth available and take away from what could have been used for motion. You can easily test this by converting one of the trouble episode at fixed quality (75%) and see if the problem persists.

I understand you want to do like your favorite poster and you need the episodes to be that size. You might want to look at converting to some H264 CODEC variant; try it in Handbrake. Only problem, it might not work with your hardware player. You might have to use DL discs or put the seasons on more than 1 disc to keep compatibility with the player. You can use Mediainfo to see which CODECs and bitrates the other guy used with his conversions.

[TvMind]

Thanks nic2k4. I have tried one pass default 75% and still same problem. I appreciate your analysis of the situation, but don't judge the quality from the sample I uploaded, the black and white episodes have alot of mosquito (?) noise, I noticed. But like I said I have never achieved smooth motion with any material, from different sources, and players.

No h.264 is not an option, at this time. Can only play xvid/divx on a crt tv ! (yes I'm old). I do have a media info program GSpot, I've been using. Like I said the poster has capped WGN cable (much inferior broadcasts to studio quality feeds I record! - maybe too good ?) and used Divx (DX50) / mp3 at fixed file size to fit one season of a show on one DVD9 disc, and no jumpy motion, but albeit at lower pq, but still ok. Originally I planned to use double his size to 350 MB/episode and use two discs instead of squashing all 36 eps on one.

I did some forced setting today - force IVTC when hybrid - (these are telecined 3:2, tested in Vdub). I am starting to record these broadcasts (I should really call them feeds) at a higher bit rate (10 Mbits/sec) or XP recording for even higher quality.

Btw , jitter is not the correct term upon reflection, it's more a jumpy movement, not smooth, as when someone runs across a room for example.

[hello_hello]

If you could use AutoGK to encode the sample you uploaded a few posts ago and upload the encoded version it might help to better understand the problem. Along with the AutoGK log file so we know what it's doing.

It doesn't sound like it's definitely a compression problem to me. Rather than overly-compressed video tending to look blurred during motion, that tends to be where it gets the most blocky, although I suppose it might look the same when the video is playing. Given you say it's blurry and jittery, it sounds like AutoGK might be getting the de-interlacing/IVTC wrong, which would be unusual, but anything's possible.

After playing around a bit more, there seems to be a lot of motion blur in your sample without actually re-encoding it. Below is a screenshot after IVTC has been applied. It's the uncompressed video directly from AVISynth.



For the record, MeGUI detects the sample as being "Hybrid film/interlaced, mostly film", but it seems like straight IVTC is all that's required to me. I like in PAL land though, so what would I know.....
I'm even starting to wonder if maybe the source was converted from a different frame rate to begin with and some of the problem is frame blending. Someone more clever than I may have a better idea.

Anyway, because you say the encode looks okay using VLC, but not when using your DVD player, maybe the process of applying pulldown to the 23.976fps progressive encode is making already blurry video look worse..... I don't know.... I live in PAL land.

PS AutoGK shouldn't cause clipping when converting to MP3, although it does "normalize" (adjust the volume so the peaks are at maximum). If there's clipping, then it's most likely on the playback side.

[jagabo]

I have never achieved smooth motion with any material, from different sources, and players.

You can't achieve smooth motion with 24 fps material. 24 fps is inherently jerky. Only made worse by a telecine to 59.94 fields per second. Film (24 fps) isn't as smooth as video (59.94 fields per second).

You could use advanced motion interpolation techniques but that will create lots of artifacts.

I believe that particular video was sped up in some non panning shots to reduce the running time. So it can't be cleanly inverse telecined to 23.976 fps film frames. The smoothest you'll get is to smart bob to 59.94 fps. Your player may not be able to handle that though.