[MKANET]

I have exhausted all my resources to find a FREE or cheap shareware utility which will detect and fix any mpeg2 errors. Below, is what I'm trying to accomplish:


I am trying to convert 2 hour hipix recordings to a format which is acceptable to TMPGEnc.


The only way I know how to do this is by using either Ben Cooley's HDTV2DVD utilty or Xmuxer to to convert ts->mpeg2. I then use DVD2AVI to save a .d2v and .wav file acceptable to TMPGEnc.


Its a sure bet that I will eventually receive an error message from TMPGEnc saying there is an error in the video with no way to recover and continue.


Although, the Hipix doesnt seem to mind when there are packet errors once in a while, encoders seem to require perfect 100% error-free video and audio.


Can somone please help? Am I the only person that's ever tried to downconvert 2 hour HDTV recordings to smaller formats? I have no problems doing short clips.


Things which I already ruled out:

1) There isn't a 2GB file size barrier in any of the apps that I have used or my OS.

2) I have plenty of RAM 768mbs with several dozen GB's of free disk workspace.


PS: I have already consulted with Ben Cooley and Trbarry and they aren't sure either since they have only experience with short clips.


PPS: I have already posted on the TMPGEnc sub-forum of www.doom9.org with plenty of views and no responses.


Thanks in advance!

Michael

 

[trbarry]

Michael -


You hadn't exactly told me what you were doing, and I don't think short/long clips weren't even mentioned. The version of DVD2AVIT3 and MPEG2DEC2 that I previously posted ( www.trbarry.com/DVD2AVIT3.zip and www.trbarry.com/MPEG2DEC2.zip ) have been modified to have huge buffers. The point here is that during motion comp in mpeg2 decode any garbage data would cause these programs to try to reference off the end of the buffers, and crash.


So if you used these versions directly on the ATSC stream (don't demux first) you might get away with it. But I'd still recommend doing less than an hour at a time if you anticipate problems. It makes it easier to isolate problem segments.


Remember that if the pid numbers are not 11&14 you will have to still set them in the DVD2AVI.ini file. Bring it up in DVD2AVIT3 and try preview.


- Tom

 

[MKANET]

Hi Tom, I dont think the problem is related to how large the mpeg2 files are since I have even had problems with a

 

[MKANET]

Aha...I spoke too soon. I just loaded a transport stream file into DVD2avi. Hopefully skipping the re-muxing to mpeg2 step will avoid the errors. I will report back.... thanks again.

 

[trbarry]

Michael -


You are almost certainly correct about the probability of errors rising fast as the file size increases. ATSC transmission is error prone and subject to dropouts, requiring a robust decoder which we don't really have.


But say you had a 99% chance of success with a one minute file. As you increase the file size in one minute increments that chance goes more or less like .99, .98, .97, .96, .95, .94, ...


If I just tapped the button on my calculator enough times that would give only about a 54.7% chance of making it all the way through a 1 hour file and less than a 30% chance of doing an entire 2 hour movie. These are all just made up numbers but you can see it generally sucks.


However the different decoders fail in different ways. So if done in sections then there is often a working decoder for each section. For instance one of my Buffy captures could only be done using Avisynth DirectShowSource with the Elecard dshow filter. But that is not a universal solution either.


I helped the problem with DVD2AVI just by making the buffers big enough to avoid addressing exceptions on garbage data but there is still more work to be done there. Eventually if I get around it I'll probably just trap the errors and spit out the previous successful frames. But this has to be done in a way that avoids subsequent sound sync errors.


This is obviously not yet a user friendly process.


- Tom

 

[MKANET]

Tom, last night I combined 45mins worth of TS files together 5.63Gb and tried to load it into the latest DVD2AVI. DVD2AVI stops responding to the system when I try that. I probably wouldn't consider converting less than 45mins at a time. DVD2AVI accepts and loads large Mpeg2 files just fine; just not TS.


I'm not too sure whatelse to try. I think I found a utility which will fix the errors: http://www.pixeltools.com/MpegRepair.html However, I dont think it's free.


At this point, I am guessing there's no easy way to convert 2 hour Hipix recordings to smaller mpeg2 formats without jumping through several hoops. I have no choice but to wait for someone to make a freeware utility which fixes mpeg2 errors or find a cheap encoder which will detect mpeg2 errors and fix them on the fly.


Above, I had mentioned that I presumed NOBODY had tried downconverting >=90min Hipix recordings since I haven't heard of anyone complaining about errors before; which seems to be a significant problem to mention.


I am open any feasible solution other than juggling with different encoders to see which one *may* be able to handle a specific error. I would have to wait through several hours of encoding just to see where an error will occur (not feasible if you want to regularly do this); such as converting a season's worth of Buffy to sVCD's.

 

[Roginator]

I'm not altogether sure about your problem, but have you tried PVAStrumento.exe? It fixes (mainly by deleting) bad spots in MPEG2 stream files such as are produced by the Creative VideoBlaster VCR.


I hate to think how slowly this would run on a large format file, as 640x480 is slow enough.

 

[MKANET]

Roginator, yes, I tried PVAStrumento after Trbarry suggested it to me. I noticed that Hauppauge also recomends this app as well. The app crashed after about 2 hours into repairing a file at 0 percent complete. I noticed that my OS swap file grew up to about 2gbs before it crashed. I dont think it was made for very large files; probably has a two gig barrier.


The the MpegRepair tool that I mentioned above looks perfect to do the job. It even mentions fixing HDTV files. I would probably buy it if it's around $29 or so; with my luck, it's probably $2900.00...