General discusion about MPEG2 sync issue....

[fingernailX]

This issue has been my only complaint about MainConcept's MpegEncoder. I needed to reencode LOTR Part 2 from SVCD to DVD-R and I have to demux the 4 mpg files, run through restream to remove the pulldown flag, encode the video and audio separately and then remux. If I just load the mpgs it gives me a correct 23.976 fps for the video but a shorter length the audio is the right length and it will encode all the audio but freeze the video at the time (number of frames/29.976). Hopefully they will consider a way to address this in 1.4 release

[rhegedus]

Do you mean time ? And by "encode to separate streams" you mean de-mutiplex ?

Yes. My de-multiplexed audio and video files have different time lenght.

Yes, I mean time. wrt 'encode to separate streams', I mean clicking the 'Output video and audio to separate elementary streams' tab at the end of the wizard.

Shouldn't the audio and video streams be equal in length?

Regards,

Rob

[Nelson37]

SUCCESS!!!!!

Testing strongly indicates that running video through Sima Copymaster ($39.95) has solved my problem!!!

METHOD - real-time, 30 min cap from Toon Disney, MPEG-2, variety of bitrates and settings. Attempt to cut last half of episode after 2nd commercial break.

Original file in synch played through WinDVD, OOS played in Womble. File cut with TMPGenc in synch, but cut point off by 10-20 seconds on both ends. Womble cut file OOS.

Captured through SIMA, Womble now plays original in synch, TMPGenc cut is now at accurate point, cut file plays OK. YIPPEEE!!!

[donpedro]

Nelson37,

Can we call "Sima Copymaster" "Time Based Corrector" ? Where di you get it from ?

[Nelson37]

I have seen people say it is not a "true" TimeBase Corrector, not sure what that means. It is intended to remove Macrovision, which is embedded in the Timebase stream(?), anyway, replacing the Timebase info eliminates most forms of Macrovision. As for exactly what it does, I am not sure, though it does remove both the repeating frames and Brightness pulsation forms of Macrovision, and it also seems to have solved my problem.

Up until 6 mos or so ago, I could not find a store in town where anyone even knew what it was, much less sold one. Best Buy and Circuit City both carry them now.

Interesting that only the Video goes through it, Audio is not connected to the SIMA CopyMaster at all. I am just now doing a full-length edit and copy with it, so far all results positive.

[mazinz]

if you see no padding streams while demuxing the clip in tmpg, then your stream did not need them which is the case with clips now used through the tbc.

a tbc can go anyhwere, you can hook in your cable to it and then out of the tbc and into your pc. ith as all ther rca/rf cavbels built on it.

[Nelson37]

CRAP - crap, crap, crappity crap.

My bad, one of my capture settings had changed. Bitrate was set to CBR, this is what solved the problem. Reset to VBR, same old errors.

What is really odd is that TMPGenc cuts and MAINTAINS audio synch, as neither Womble nor M2-Edit will do. The edit points are just offset by about 10 seconds before where I set them, on both ends of the file, and yes, the offset seems to be variable. CRAP!!!!!

I did try a test clip with WinDVR, which edited OK, but not sure about bitrate settings. CBR seems to be the key to getting an editable MPEG-2 file.

[dvasco]

CRAP - crap, crap, crappity crap.
The edit points are just offset by about 10 seconds before where I set them, on both ends of the file, and yes, the offset seems to be variable. CRAP!!!!!

Nelson, I still think you need to reencode with added I frames or somehow capture with more I frames so you can edit at the points you wanted to. It is supposedly only at the I frames that editing can be done. Whatever you do I think I frames are your solution. By the way is the audio oos when you play the Womble edited piece in WinDVD or PowerDVD? If not, when played back on a hardware DVD player the audio should be in sync.

[Nelson37]

More I frames may solve my problem, but will require re-encoding which defeats the whole purpose. My normal method is cap I-frame only, 12MBPS, CBR, demux, edit, resize, and re-encode. That works fine, but is those very steps I am trying to eliminate.

Tmpgenc is doing more than just going to the nearest I-frame, SFAIK the gap between I-frames should be less than one full second.

I can get very acceptable quality and small size with real-time encoding, BUT no edit. CBR or I-frames-only lets me edit but balloons the filesize so as to require re-encoding, if I must re-encode I might as well use my normal method.

I have tweaked real-time settings to get 60 minutes of good quality video in less than 800 MB, HOWEVER, being unable to edit defeats the purpose.

Yes, Womble edits are way OOS, several seconds at least. Have not tried playing these clips on DVD standalone, that is worth a shot. Am also going to test to see if Womble is OOS to the same parameters that TMPGenc cuts are inaccurate. Not sure how that may help, but it may indicate a possible course of action.

[drewson99]

If you are using Ulead then that is most likely the problem. I had this problem, where at the beginning of the movie it was fine, but by the end it was off by about a half second.

Ulead made a patch for this and other problems, which can be d/l from their website.

As for MPEG2 in general, I have found that editing mpeg2 is a farce. I ALWAYS end up with synch issues when using merge/cut etc. Best to cap to avi and edit with Vdub, then encode the final run avi to mpeg all at once.

It took me almost two years to give up on capping and editing mpeg2.

[donpedro]

Best to cap to avi and edit with Vdub, then encode the final run avi to mpeg all at once.

You missed important information. I am using external hardware MPEG2 encoder, so I can't cpature AVI. The whole purpose was to get rid of AVI->MPEG2 encoding (time consuming). I'll keep playing arround this issue.

[drewson99]

sorry, my brain is fried, I hear "cap to mpeg2" and I think "All-In-Wonder"

ZZ

[Nelson37]

OK, I have developed a way to edit with synch. I am using AIW 128, MMC 7.6, MPEG-2, Default GOP, Motion 100. Have tested with 352, 480, and 720 x 480, with and without De-interlacing. This should work with most any VBR, MPEG-2 file.

This is primarily for editing commercials out, uninterrupted movies seem to be easier to edit.

First cap your file and rename to FILE.MPG, if necesary. I have been testing running the Fix-Time.exe on this, seems to help smooth playback but is not mandatory.

Open M2-Edit. Go to Panels, the Navigator, Composer, and Storyboard should be selected. Go to File, Open and select your MPG file. Depending on file size, it may take a minute or two for the storyboard to show the file sections. It will split the file arbitrarily into 11 time-equal segments, of which the first one always gives an error later on. Current solution is to start cap a little over 10% early, ie for a 60-minute show, start about 7 minutes early.

Now, starting with the second clip, which should contain the beginning of your show, drag the segments into Composer one at a time. For each file, select File, Generate and name them CLIP_1.mpg, etc. Then clear the Composer window and go to the next clip. Joining any or all clips, or attempting to cut in M2-Edit results in OOS.

So now you have 10 individual MPEG2 clips. Open TMPGenc ( I am using 2.54), go to Merge and Cut. Select Mpeg2, SVCD setting. Then hold CTRL and select all 10 files in reverse order they will open 1 to 10 in Merge. Open each segment and Edit commercials from each end. There is probably some mathematical proof of this but 6 out of 6 1-hr test clips, there is always one segment that has a commercial in the middle, so I have to insert the clip a second time, once for the beginning and once for the end. Anyway, after edit all 10 (or 11) clips, name the output file and run the Merge.

This results in Perfect Audio Synch, most of the Merge points come at the commercial breaks, those within the show are barely noticeable.

Still testing a way to eliminate M2-Edit from the process, but nothing else has worked so far.

[theboss777]

Nelson, I have tried your method, but I get a stutter between clips that I join in TMPEng. I mean the clips that M2 created.

[Nelson37]

Modification of method. Use M2 to create all between-commercial clips. Pass to Storyboard and then to Composer, generate and join with Tmpgenc as before. This way the slight stutter comes in the blackouts between commercial cuts. There will be fewer of them, as well.

I'm still working on this, I had been so damn happy to maintain audio synch after editing that I wasn't bothered by the joining stutter until I played a few.

[donpedro]

I didn't progress with this issue too much, since I didn't have time, but let me add some more cofusion abut this issue. I authored another DVD from file that was captured by PCTV Deluxe.

- Captured by PCTV Deluxe hardware mpeg-2 encoder
- File played on PC with WinMediaPlayer and PowerDVD = in-sync
- Authored with
- Played from DVD on PC with PowerDVD = out-of-sync 0.5s on the end
- Played from DVD on PC with MediaMatics DVMatics DVD player = in-sync

I will update result from standalone player later.

I just don't get it .... How come that one sofware will play it in-sync and another not ? Is it possible that you can get different results from different standalone DVD players too ? Don't they use "sofware" in standalone DVD players too ?

[Nelson37]

YES, different software will DEFINITELY give different synch results. I find WinDVD most accurate in simulating my DVD player, STHSVCD is good, as well, but I haven't used it in a while as I am testing AC-3 and WinDVD supports this.

Have some more info regarding the Padding Stream. Original MMC cap has stream, about 1% of file size. M2-edit generated files have stream approx. 10% of filesize. After run thru TMPGenc Merge, stream is still there but Demux reports 0.0 MB. All files play OK in WinDVD. Merged files play fine in standalone.

When attempting to Cut the cap files in TMPGenc, the Audio will stop as much as 2-3 minutes before Cut Point and the Video about 1 minute after that. This is highly variable and based on clip length, I think. Files run thru M2 will edit accurately in TMPGenc, though.

I think broken GOPs may be the issue, as M2 is supposed to rebuild GOPs when editing. ReStream is supposed to do this, will try and post results.
There ought to be some simple, inexpensive process which will "correct" these files so they can be edited accurately.

[Nelson37]

Update on ReStream.

Demux, Restream, Remux, 1 Gig file shrinks by 6 MB, finished file plays correctly and is accepted by TmpGenc Merge, almost all other remuxed files do not play and the time counters do not move in TmpGenc.

BUT, it still will not edit on a precise point, cuts are a minute or more off. The cut file DOES play in synch, though.

[gadgetguy]

I'm a little tired of seeing Ulead being dissed. It does a good job of editing mpeg exactly at the cut points defined. I do have audio synch problems that I used to blame on Ulead, but I've since changed my opinion. I have found that if I capture video through my camcorder as an AVI, then encode to mpg using TMPGEnc, I can then edit the video all I want in Ulead and it never has an OOS problem.

[rhegedus]

I'm a little tired of seeing Ulead being dissed. It does a good job of editing mpeg exactly at the cut points defined. I do have audio synch problems that I used to blame on Ulead, but I've since changed my opinion. I have found that if I capture video through my camcorder as an AVI, then encode to mpg using TMPGEnc, I can then edit the video all I want in Ulead and it never has an OOS problem.

Re: editing mpeg exactly at the cut points. Isn't that what it is meant to do? A lot of freeware software does that for....free.

The synch IS a Ulead problem, because the mpegs produced by TMPGEnc must be in synch otherwise you wouldn't use them. Ulead released a synch patch for MF1 but it looks like they forgot about it for MF2. Try contacting Ulead about this and then see if you wouldn't diss them too.

Regards,

Rob

[gadgetguy]

My experience with the freeware is that it never cuts the video where I define it, but at the nearest I-frame or someplace else as some others have noted.

My point is that when the original file is 100% correct then any editing in Ulead doesn't put it out of synch, but if the file is from a source that may not be 100% is when there is a problem. If it happened regardless of the source file then I would blame Ulead, but because the source file makes a difference I don't. As far as Ulead "the company" I make no claims for or against them or their support. I did not purchase the Ulead software seperately, it came with my firewire card, so it was "free" to me. I have not had occasion to seek support from Ulead, but my experience with most manufacturers Customer Service is the same as my opinion of "help" files. Help files don't, and Customer Serves Us.

[rhegedus]

My point is that when the original file is 100% correct then any editing in Ulead doesn't put it out of synch, but if the file is from a source that may not be 100% is when there is a problem.

My experiences with DV capture have lead me not to use Ulead MF2 any more. The Capture DV avi is in synch, the mpeg produced by TMPGEnc is in synch, but the DVD output of Ulead MF2 is out of synch. If I author using SpruceUp, then the DVD is in synch. This shows that it's not the source file or the encoded mpeg that is at fault, but Ulead MF2.

There are plent of posts on this matter - I would link them here but the search function is a bit slow of late....

Regards,

Rob

[Nelson37]

Ulead will edit MPEG-2 without re-encoding? Will have to try that, though it sounds like it may have trouble with real-time Mpeg-2 caps.

Anyway, more info on M2/TMPGenc combo. Original cap 1.06 Gig, 7 Mb padding stream, running entire file through M2 yields 1.58 Gig file with 160 Mb padding stream. Video freezes in TMPGenc but audio plays, file cuts accurately and in-synch.

So it has nothing to do with M2 cutting or breaking up the file, M2 is doing something, primarily involving the padding stream (possibly), which is in some way correcting the file so that TMPGenc can cut it correctly.

Does anyone know EXACTLY what the heck this padding stream does, or contains?

[furball6969]

I regularly cap 8-10 hour VBR mpeg2 caps from DBS; cut with TMPGEnc into separate movies, Demux with TMPGEnc, import into DVDMaestro and burn to DVD with no sync issues.

[Nelson37]

Furball, this is interesting, my capture and cut methods are identical to those in your guide, though I burn on CD and pre-test with WinDVD. My cut points are off by half a minute or more, up to 2 or three minutes.

What version of Tmpgenc are you using? I have tried several 2.x versions.

[furball6969]

Nelson37

I had never noticed this issue with TMPGEnc but have seen quite a few posts regarding it so I decided to test it.

I just cut a 30 second commercial out of a 45 minute clip and the cuts are bang-on accurate, with no sync issues.

The TMPGEnc I'm using is 2.58.44.152 and the clip specs are: 352x480 mpeg2 vbr 2.3mbit capped with AIW.

[Nelson37]

Some new info. Cutting end of 60 minute clip, TMPGenc time counter indicates 51:10 at cut point, does NOT cut where video is displayed. Same clip "corrected" through M2-Edit indicates 52:30 at same point, and cuts accurately using TMPGenc. Corrected clip at 51:10 displays the point where TMPGenc cuts the original clip.

Additional tests reveal there is a time discrepancy of about 12 seconds at 1:30, 43 seconds at 10 minutes, with 80 seconds at 52 minutes. So while it increases with time it does not seem to be regular, nor any multiple involving frame rate change or something similar. Capture indicates no dropped frames.

So the problem involves either Time Counters directly, or something which affects the timekeeping of the clip.

Clip captured using similar settings to Furball's stated above.

[Nelson37]

VDUB reveals M2 clip is one frame smaller, with one more I-Frames and two less B-Frames, total 108, 253. Audio is 21 frames shorter at 150,500. This is compared to the original AIW capture, one hour of a Digital Cable movie - no commercials. Vdub displays identical keyframes at the correct 52:30 in BOTH files.

I wouldn't think the slight frame difference would be that significant, but all processed files are same as original, M2 file is only one that shows any significant difference, in these parameters, anyway.

So whatever it is, VDUB and M2 can do it. Demux, Remux (both Simple and non-Simple), with or without ReStream, Time-Fix, and/or TMPGenc apparently can't for some. FurBall has a Radeon and Win2K where I have a 128 Pro and XP Pro, anyone else with problems and/or success to round out the database?

I just realized that since Vdub can give me a precise time count with video preview, and TMPGenc CAN cut accurately WITH AUDIO SYNCH if given a corrected time count, I can cut accurately enough to remove commercials WITHOUT using M2-Edit Pro! Makes it a 2-step process, and cutting multiple commercial breaks is going to be a pain, but it is doable.

[furball6969]

I've capped a small clip that shows how I make accurate cuts with TMPGEnc without sync issues. The clip is Here!

[Nelson37]

Just an update -

Using VdubMod to get correct Time of cut and TMPGenc to cut by manually entering times works fairly well, variances down to a second or so. Still get some brief flashes of commercial when the fade-out is short but much better.

This also works with the files encoded with the ATI real-time IVTC!