Deinterlace problems with playing backup

This is the first time its happen since I’ve been using dvd2one but there is a deinterlace problem when playing the backup copy of the movie " Robocop - Dark Justice ". Everytime the camera angle changes in the movie, for about 1 second, you can see the problem. Its really bad that it makes the movie almost unwatchable at times. Anyone else ever have this problem with other movies? Will there be a fix in the next release of dvd2one?

Yeah, that’s the problem with interlaced images: They need a ton of bitrate, as compared with progressive scan. If you reduce the bitrate too much, you wind up with the effect you’ve described. You may end up having to back this one up the “old fashioned” way, using a program like TMPGeng (demo version availible in the “downloads” section of Doom9.org) and IFOedit. That way, you can de-interlace the frames while re-encoding, and not have that problem anymore. I’m not exactly sure if InstantCopy will do a decent job on that sort of stream, or not – but if you want to try it, the demo’s DVD capibilities are fully-functional, and is availible at Pinnacle’s web site.

Thanks for the tip. I guess I can live with a coaster and without this movie backed up because once I’ve started using dvd2one, the other “old” way just takes way to long to do. I would just like to know if there are any other movies that cause this problem so others and myself would not was more dvd-r’s.

I totally agree that the “old school” method’s just a wee on the time-consuming side. What, none of us have anything better to do with our lives than to babysit our computers during a twelve-hour encoding job? Or sitting around while DVD Maestro chews on our streams, only to be told that we overshot the overall bitrate – and wind up spending another twelve hours redoing everything? Having trouble lining up our chapter points? Synch problems in our sound streams? And let’s not EVEN get started on handling episode DVDs, where everything’s on one set of VOBs!

(Get the feeling this subject hits a sore nerve with me?)

On subject, though, out of curiousity, I ran one of my Star Trek, TNG, DVDs through InstantCopy to see how it handles interlaced material. It looks pretty good, considering that it is, after all, a copy. If I were you, I’d download the trial and give it a try on a rewritable. It’ll never beat DVD2ONE’s speed – and it NEVER acurately predicts the file size – but since it re-encodes everything (and DVD2ONE only recompresses it), that just may be why it handles interlaced streams better than DVD2ONE seems to. *

But if it works for you, it works! All you’d have to do is run your copy back to your hard drive via DVD Decrypter (or Smartripper), then burn your DVD-R. If it doesn’t work… well, you’re not out anything, at least.

*NO offense, Rene + Irwin! Don’t mean to recommend the competition when I personally prefer DVD2ONE any ol’ day of the week over InstantCopy, but fair’s fair and a test is a test. On progressive scanned images? I always wind up with BETTER results using DVD2ONE, since I’m actually able to use the entire disk’s storage capacity. Now that I’m finished brown nosing…:bow:

How can you know if a DVD is interlaced?

One way to tell is to study the image for “stair stepping” effects and zebra patterns… but that’s not always an accurate way to tell, since high bitrate interlaced images can look pretty damned good. Plus, this method really can be dependant on the quality of both your playback devices and your monitor/video card.

If you really want to know for sure, download and run DVD2AVI in the “preview” mode. It’ll tell you pretty much everything you’ll ever want to know about the stream. Another good program is Bitrate Viewer, which is indispensible for those who decide to go the CCE route.

Because of the nature that interlaced frames are displayed, they tend to require a much higher bitrate than what a progressive image would need: Progressive scanned images display full frames (usually at 23.97 frames per second NTSC, pulled into 29.97 overall), while interlaced frames only display one half of the field the first frame, then display the remaining half during the next frame. This is, naturally, an overly-simplistic explaination of the way this works, but the point is that progressive frames tend to compress better than interlaced fields. If your source was shot on video, then count on interlaced frames. Film? Usually progressive.

And, by the way: Sorry for mispelling your name, Erwin!

writersblock:

I am quite unable to see why a higher bitrate is needed for interlaced video. Since each frame is smaller than progressive, I would have thought that, if anything, fewer bits were required.

I’m not saying you are wrong, but this is the first time I’ve heard of it. Can you cite any references for this assertion?

-Pete

@Peter McCall

I’ll do some digging and see what I can come up with as far as “concrete” references for you… it’s been awhile!

Basically, the bits used in encoding the image itself aren’t the only ones used in the process of MPEG2 conversion; some of the bitrate used goes to “blank” information, or the spaces between scan lines, in order to preserve the aspect ratio. These “spaces,” of course, get filled in during the following frame with visual information… but the scan lines that were there before are now blank. (It actually takes two seperate fields at half resolution to equal a single, full, field.) That’s the first part of it, but not quite ALL of it: The more information you take from the active lines, the more obvious the INACTIVE lines become. This leads to the zebra patterns and stair-stepping that we all love so much – especially in scenes involving movement against solid colors. Most deinterlacers work by simply doubling the field, thereby creating an image made completely by active information – which can be whittled away quite a bit before the human eye notices it much, since there’s no “blank” scan lines present in each field for contrast. Interlaced images with high bitrates tend to be “juicy” enough that – sure, there’s visible lines running through the image – the image is vibrant enough to appear fluid.

I remember reading most of this in a report (I think it was posted on Thedigitalbits.com – but damned if I’m positive) back when dual layered disks were first being introduced (it was an argument as to why the extra storage space was needed). But, like I said, I’ll dig and try to give you something to go on!