Problems burning dvds from mpegs on Mac

[tsp1965]

Hi all

For years I've been recording TV using EyeTV and creating DVDs from the mpegs it makes in Toast. In the interests of speed I'd have Toast set to never re-encode and this meant it only took the time to multiplex ~ 20 mins per DVD including burn time. I've used every version of Toast from 5 to 10, upgrading when necessary, virtually all disks fine.

Then a number of things changed. I installed Lion. London region went digital. Suddenly I find that most of the disks I make (by the system which always used to work) don't work, either on my DVD box (same one before and after) or in Apple DVD Player, Windows Media Player or VLC. I tried lots of things - reinstalling QT, reinstalling Lion, no joy. Lots of coasters being burned with miscellaneous problems - poor lip sync, skipping, freezing near the end of a title (particularly the second title on the disk). There was no common factor in the editing software either. Some were just exported out of EyeTV to mpeg, some edited frame-accurate using VideoRedo H264 Suite for PC, either on a virtual machine or on a real W7Pro box.

Mountain Lion came out, so I downloaded in the hope of a fix. Nope, same problem. In every other way ML is a big improvement on the awful Lion.

I use Verbatim DVD-Rs, which are good disks. I also know that when I burn the old way (no re-encoding) to a disk image, the image when loaded into DVD player exhibits the same problems as the burned disks. So I don't think it is media problem (I also tried different brands but same problem).

In desperation I tried letting Toast re-encode (it was set to Re-enode: Never, now set to Re-encode: Auto) - bingo, disks which play smoothly. The down side is that Toast now always re-encodes and it takes virtually all day to burn one disk. In fact some have to re-encode twice because Toast isn't so good at estimating the final disk size when it re-encodes (so you set a disk which it thinks will be 4.1GB, it takes four hours to re-encode then bombs out before the write because it's actually 4.4GB: solution is to write a disk image then use shrink-to-fit if it is too large, re-encoding for a second time).

So I've gone from burning disks quickly at the same quality they were broadcast to burning disks very slowly at a reduced quality, but at least they work!

What I deduce from all this is that because Toast is always now choosing to re-encode, it is detecting some DVD format non-compliance with its source mpegs. If I don't re-encode then the disks play poorly because of this non-compliance. If I do re-encode, then this non-compliance is dialed out. Did anything change when we went fully digital that might have caused this?

I just can't figure out how to work with Toast now, as I can't have it encoding all day every day like it has been.

Can anyone shed any light on what's going wrong, please?

Thanks in advance for any ideas.

TP

[jman98]

Yes, you are very likely getting screwed over by the conversion to digital TV. The DVB standard supports video AND audio codecs that are invalid for DVD. DVB doesn't HAVE to use those, but probably in your case they do. I live in the USA where we have a much simpler (not saying that means "better" - just saying it's a lot less complicated) standard for digital TV that is a lot more DVD friendly as most (but not all) of the TV providers use MPEG-2 for video and AC3 for audio, which are DVD compliant. I'd guess that your video is probably H.264 and I have no idea what your audio is.

Thank you for posting to the Mac forum as unlike most newbies, you have correctly realized that if your question involves a Mac, it needs to go on our Mac forum to get you the best help. You may wish to consider moving into making BluRay discs (however that is done on a Mac) because your TV broadcasts are likely valid for BluRay if the audio is not MP3 and that would at least save you the painful time of conversion. You could also consider buying a DVD recorder and letting it do the recording for you as that would also save you time. I don't see a good way for you to convert TV files quickly on your Mac to DVD format.

[orsetto]

jman98 is usually great at identifying such glitches, so he's probably right about the codec changes in DVB-T being a root cause of your issue.

Your two other problems:

1. OSX Lion broke just about everything that worked fine under Jaguar, Tiger and Leopard. Apple has exhibited no interest whatever in attending to that, and doesn't even consider it a problem (Mountain Lion didn't do a damn thing to help me). Software developers have been slow to update their apps, and in some cases the updates suck or they may never update. OSX doesn't have nearly the variety of video options as a Windows PC, so if a workflow we depend on gets hosed by an OSX "upgrade," we end up screwed into the ground with no alternatives. Since your Mac can apparently run under Snow Leopard, try installing the older OS with EyeTV software and Toast on an external boot HDD. If everything goes back to normal, the problem is definitely Lion related.

2. Toast is a kludge. Its a very nice kludge, many of us use it simply because its been around forever and offers tons of features. But many of those features don't really work consistently well, including its DVD authoring (you may discover one day the discs you made with it won't play on some other piece of hardware). Throw the ugly Lion transition into that mix, and you have a mess on your hands. Its actually rather surprising you haven't had intermittent trouble with Toast long before now.

I love my Macs, but gave up on doing anything DVD-related years ago: it just isn't worth the aggravation. I use DVD/HDD recorders for my TV archiving. Any videos I want from the web I download on the Mac (to bypass all the stupid Windows trojans), then move them to my Windows laptop where I use DVDflick or AVStoDVD to convert/author them to DVD. Until OSX Lion shakes out its horrors, which may take quite some time yet, you might need to consider getting a standalone DVD/HDD recorder for day-to-day TV recording: I think Panasonic is the only brand left in UK, get one now while you still can.

Otherwise, you could well be stuck dealing with the much slower re-encode-before-authoring workaround. EyeTV forums might have info on settings you can tweak to optimize output files for DVB-T/dvd compatibility, or it may be that you need to change the initial output from MPEG to another container format like MP4. If you have access to a separate Windows PC, offloaded conversions can be reasonably quick while keeping your Mac free for other work. After transferring MP4 files from my Mac to my cheap i3 Win7 laptop, I find DVDflick will typically convert and DVD author two to three hours worth of MP4 video within 70 mins. With a borrowed i5 Lenovo laptop, it took only 43 minutes.

[tsp1965]

Hi and thanks for the replies

In the UK most channels encode as 25fps mpeg-2s at 704x576 or 720x576 (PAL DVD Compliant), but a few encode at 544x576 which has to be converted first (or re-encoded). Audio is mpeg layer 3 at 48khz, which is also DVD compliant. The only thing which might have changed recently is the GOP length etc.

99% of my DVDs are prepared by taking the EyeTV mpeg output and saving it onto a PC for frame-accurate editing out of commercials and pre/post schedule content, for which I use VideoRedo (in the absence of a good frame-accurate editor for the Mac). Sometimes I do this on a W7Pro VM on the Mac, but mostly it's on a separate W7Pro box. My understanding is that VideoRedo produces DVD compliant output by default and recalculates GOP lengths etc to ensure they are compliant. That's what it does when it does a Quickstream Fix and I believe that's also what it does when it does the intelligent re-code as it produces the edited output.

So even if the TV channels changed their settings when we moved from mixed digital/analogue to digital-only, I would have expected VideoRedo to pick that up? As far as I can see the movie properties of old mpegs which worked and newer ones which don't are exactly the same.

As to Snow Leopard, I did try rebooting with an external backup drive running SL and used the new mpegs to write DVDs but had the same problem, so I don't think it is OS related.

It's all a bit of a mystery!

Thanks anyway.

[tsp1965]

For the benefit of anyone following this thread in future, I think I've got to the bottom of it.

VideoRedo's standard mpg export profile actually leaves the GOP length set to whatever was in the input file rather than changing it to 15, which is the PAL standard maximum by default. I'm guessing that when they did the digital switchover in London they took to using different encoding conventions, because the GOP lengths are often significantly longer than 15. The theory is that these longer GOP lengths are coped with by modern software players, but in my case that doesn't seem to be true.

To test this theory I remuxed several troublesome mpegs using VideoRedo setting the max GOP length to 15 and 'bingo', they play just fine when muxed (but not reencoded: Re-encode Never back on) by Toast.

You can edit the profiles used by VideoRedo by looking for the file OutputProfiles.xml in the VideoRedo folder in your Documents folder and editing the 0 in the line(s) relating to each profile's Max GOP Length from 0 to 15. That saves you having to remember to change it using the advanced Options each time you output. It takes a minute or two longer to output when it shortens the GOP lengths, but that's a small price to pay.

[Herve]

For the benefit of anyone following this thread in future, […]

so, I will correct error

[…]GOP length […] to 15, which is the PAL standard maximum by default.

15 is too long, do not use it for the maximum length for DVD-VIDEO in PAL.
The norm says: VOBUnit can not exceed 0.5 second and encoders make 1 GOP with only 1 VOBU. So this GOP size is out of DVD-VIDEO norm. (Prefer to use a 12 length GOP max in PAL. I know that GOP is not VOBU …but here, you have to conform to VOBU specifications )

The theory is that these longer GOP lengths are coped with by modern software players, but in my case that doesn't seem to be true.

and my advice: if you use a normalized format, respect the norm (and the resulting file will be playable anywhere)

bye

[jman98]

Hi and thanks for the replies

In the UK most channels encode as 25fps mpeg-2s at 704x576 or 720x576 (PAL DVD Compliant), but a few encode at 544x576 which has to be converted first (or re-encoded). Audio is mpeg layer 3 at 48khz, which is also DVD compliant. The only thing which might have changed recently is the GOP length etc.

MPEG layer 3 audio is most assuredly NOT DVD compliant! Just FYI. But it's good that you found something that worked for you.