VIDEO_TS plays differently after burned

[oofers72]

Hello all,

I have a problem that has baffled me for a few days now and I hope one of you experts can shed some light on the cause. For months now I have regularly been compiling small clips onto DVD. Typically, I encode to MPEG, then author and burn a DVD. Never had a problem I could not troubleshoot. Until now.

I have a DivX avi file that was encoded at 2239 Kbps. It is PAL (25.0 fps, 720 x 528).

As I always do, I used TMPGEnc to encode from avi to MPEG-2. I use a 2-pass VBR with an average bit rate of 3000 (which reminds me of another issue: if AVI Codec tells me that a DivX avi file is encoded at 2239 Kbps, is this the same bitrate I should use when transcoding to MPEG-2 via TMPGEnc? My eyes tell me no. But I digress......)

So anyway, when I watch the resultant MPEG-2 file on my PC with WinDVD, everything looks fine. Furthermore, after authoring with TMPGEnc DVD Author, and playing the resultant VIDEO_TS folder, it again looks just as I expect.

However, once I burn the VIDEO_TS folder to a DVD+RW (using Nero Burning Rom), and play it back on my PC with WinDVD, there is some sort of interlacing problem. You've seen it before-- that jagged, "in-between-frames" look exists through the whole video.

Initially, I thought it was some sort of error in my encoding, so I tried various things, like using both "Interlace" under the "Encode mode:" option in TMPGEnc (I normally use "Non-interlace"). I even tried encoding as NTSC, but the problem persists.

I would rate myself at only average at understanding all the settings of TMPGEnc, and would have just researched that great program more to figure out other possible fixes if it weren't for the one fact mentioned above.....

.... that when I watch the VIDEO_TS folder through WinDVD, it looks fine, but when I burn the exact same folder to a DVD+RW, the interlace problem is present, and QUITE distracting.

I should also note that all the other short clips being authored on this compilation do not have this problem, when played from the final DVD+RW. And they were encoded the exact same way.

Any ideas on what's going on here, anybody? How can just transferring a VIDEO_TS folder to media make the image appear so differently in the same program (WinDVD)?


Thanks.

[mats.hogberg]

Ha DivX avi file is encoded at 2239 Kbps, is this the same bitrate I should use when transcoding to MPEG-2 via TMPGEnc?

Right - The answer is no. Source and dest bitrates have nothing to do with eachother.
For the rest of your problems - Have you tried it on your TV?

/Mats

[Cornucopia]

Maybe it's just a typo, I don't know, but I see that your source file is 720x528. Where'd that # come from? It's certainly not standard.
If you're going to standard PAL MPEG2 for DVD, you're going to want it to be 720x576. How to convert it correctly seems to be your problem.

First thing you need to do is see if that vertical # is being read correctly.
2nd, check to see if the source ALREADY has interlace issues--something that is now 528 high had to have gotten there from some other size, but how? If cropped, all is not lost. If resized, it's probably too late to do any good to it.

My guess is to pad (letterbox) it back out to 576 pixels high--so there is NO resize--and then try the various interlacing options. Look at it from both computer monitor and TV. Note: with 528 pixels, you actually don't know if it has changed its field dominance, so you may want to swap those settings also.

Scott

[oofers72]

Ha DivX avi file is encoded at 2239 Kbps, is this the same bitrate I should use when transcoding to MPEG-2 via TMPGEnc?

Right - The answer is no. Source and dest bitrates have nothing to do with eachother.
For the rest of your problems - Have you tried it on your TV?

/Mats

Yes, thanks for stating what I had begun to assume is true-- that when AVI codec tells me the bitrate of a particular file, that just tells me what bitrate was used to encode the file into the state I currently have it. Starting from there, it's up to me to determine what bitrate is optimal for encoding it from that point. Thanks for confirming my own little theory.

And yes, the problem was first noticed on the TV. But then I learned that I could just use WinDVD to see if my various atttempts at fixing the problem were worked-- I no longer needed to keep running into the living room with a newly-burned DVD+RW to see the result.

Thanks for taking the time to respond.

[oofers72]

Maybe it's just a typo, I don't know, but I see that your source file is 720x528. Where'd that # come from? It's certainly not standard.
If you're going to standard PAL MPEG2 for DVD, you're going to want it to be 720x576. How to convert it correctly seems to be your problem.

First thing you need to do is see if that vertical # is being read correctly.
2nd, check to see if the source ALREADY has interlace issues--something that is now 528 high had to have gotten there from some other size, but how? If cropped, all is not lost. If resized, it's probably too late to do any good to it.

My guess is to pad (letterbox) it back out to 576 pixels high--so there is NO resize--and then try the various interlacing options. Look at it from both computer monitor and TV. Note: with 528 pixels, you actually don't know if it has changed its field dominance, so you may want to swap those settings also.

Scott

Ok, you may have just put me on the right track.

AVI Codec is what reports the size as being 720 X 528. In TMPGEnc, on the MPEG Setting dialog box, the first four text boxes (Stream Type, Size, Aspect Ratio, Frame Rate) are all greyed out, unavailable to be adjusted by me, but they do correspond to what one expects when encoding to PAL MPEG-2 format (MPEG-2 Video, 720 X 576, 4:3, 25 fps, respectively).

So, you say first thing to do is see if the vertical # is being read correctly. After reading the file, the Expert Settings For Source dialog box's drop down-list for Aspect Ratio is set at "1:1 (VGA)". Would this imply it is being read correctly or not? I can of course change this value manually. (In fact, I neglected to do this in my troubleshooting, so my answer may lie there). But I had always assumed, perhaps erroneously, that you can't go wrong with 1:1, as it implies it just retains the original dimensions.

But what you say makes sense about the lost pixels and the padding to correct the problem. So, how can I pad it back out to 576?

So am I wrong to think it odd that the VIDEO_TS folder played fine when sitting on my hard drive, and then had this problem when trasferred to a DVD+RW? That's what really threw me. That just seemed to make no sense. It was the same folder being viewed through WinDVD, just on media now.

[mats.hogberg]

I see that your source file is 720x528. Where'd that # come from? It's certainly not standard.

Is there any standard for AVI/DivX resolutions?

/Mats

[Cornucopia]

While there are "standards" like ITU-601 that AVI, DivX or Quicktime can adhere to, there is no requirement that they do so. AVI and QT are basic, generic AV container formats, so you can, within reason, make a movie any size you like.

Most codecs require that you have certain a color spectrum and have resolutions that are multiples of 2, 4, 16, etc. But other codecs, and uncompressed, can be just about anything.

That's the problem with noobie capturing. Hardware capture cards do have a default size (very often 720x480, 704x480, 640x480) in the internal sampling, but allow for resize before being written to file. Again, it's best to stick with the standards (and in this case the default), because there is less computation with no resize, and no smearing/blurring because of interpolation. AND, less chance of interlace mess-ups.

oofers72--
1:1 refers to the Pixel Aspect Ratio. For standard AVI/DivX/QT that is created on computer, it should almost always be 1:1. Stuff that is captured from analog using ITU-601 standards, or DV material, will have a non-square PAR--usually .9:1 for NTSC.
As standard AVI (not counting DV) doesn't have a field denoting what the PAR should be, it's always a guess as to what it is. And most editing and player apps just assume it's 1:1. But that isn't always the case.

However, that whole mess probably has nothing to do with your case.
You want to have TMPGEnc place your video in "Center" VideoArrangeMethod. This will automatcally add letterbox padding above and below, to fill out to 720x576.

Looks like you're using the default PAL MPEG2 DVD template. In default, it "locks" most settings. You can always unlock them by loading the "unlock" template.

re: TV vs. Computer monitor...
Until your interlace troubles are over, I recommend you should ALWAYS check out your trial output on both Monitor and TV.

Scott

[oofers72]

Cornucopia--

I want to thank you for taking the time to answer my questions.

My problem is solved, and you put me on the right track.

Guys like you don't have to respond..... but when you do, you help guys like me learn a little more.

Thanks again.