Skip forward and back gets out of sync with playback time (1 Viewer)

adagio

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I just installed MP 1.7.1 on a new WIN 7 32 bit machine. When I am playing back recorded TV and press the skip forward (15 seconds), it will sometimes jump ahead too far, but the time of the recording does not. Hard to pinpoint a pattern, but looking at the time of the video it will say something like 31:30 playing a spot in the recording, and if I skip ahead 15 seconds it will be at 31:45 or so as it should, but will be playing the recording from maybe 50 seconds ahead. If I back space, I can then sometimes play the same section of the recording, but then the time will be at 32:30 or something. It seems if I push the fast forward,it gets itself back in sync. I hope that description makes sense. I had used MP 1.3 for a long time and never had that issue.

It happens a lot, maybe 25% of the time?

I' d be happy to send logs, but wan't sure which logs would be useful.

Thank you.
 

adagio

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Ok. I did some more testing and it is very repeatable. I've attached the logs here. Can someone look at them and tell me if they see what is going on?

I have a recorded TV video, about 2 hours long. I start playing it around the 37 minute mark. I press skip, which does 15 seconds forward, but it appears the recording has jumped further, maybe 1 minute ahead or so. I press back, which skips back 15 seconds, and the recording goes back about 15 seconds as it should. I press back again and it appears that the video skips back about a minute or so. If I just play it straight without skipping, it plays fine.

Thanks!
 

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mm1352000

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    Does this only happen with recordings from certain channel(s)?
    My [uneducated] guess is that the problem is related to PCR and/or PTS issues from the broadcast source. A short recording might help an expert to figure out what is going on.
     

    adagio

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    I record the news on the same channel each night and time shift through the commercials. So I guess I've only tried it on that channel. Didn't think it would depend on the source. I will record some other channels tonight and test it out.

    Thanks for responding.
     

    Owlsroost

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    Does this only happen with recordings from certain channel(s)?
    My [uneducated] guess is that the problem is related to PCR and/or PTS issues from the broadcast source. A short recording might help an expert to figure out what is going on.


    I agree (TsReader uses PCR for seeking, PTS for A/V/presentation clock sync). There is nothing unusual in the logs that I can see - every seek gets to within 0.5 sec of the target (PCR) position, so maybe there is a skew between PCR and PTS sometimes in that broadcast stream ?
     

    adagio

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    I recorded 4 different channels last night. I will check them when I get home from work today for the issues.

    I never had this problem with MP 1.3. Same channel, same cards, same PC. I still have my old XP drive with MP 1.3 on it. I bet if I put that back in the recording will play fine. Is that a test you'd like me to try? Seems like something has changed in that area from 1.3 to 1.7.
     

    adagio

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    I tried 4 other channels last night. An hour to a half hour each. I spot checked them tonight and could not make any of them skip funny.

    So I tried recording the 'bad' channel for 2-5 minutes to see if I could get a short sample to send. I could not make it happen with those short samples. So I recorded a sample about 20 minutes long. That one fails. The amount that it skips too far almost seems related to the total length of the recording, but I don't have a large enough sample to prove that.

    Anyway, the good news is I have a .ts file that is 'bad' The bad news is, it's about 2 gigs in size. Is that too big to get to someone to look at?
     

    adagio

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    What are some options? I can try to get a smaller problem sample, but it will probably still be fairly large.

    I was watching a recording last night and I was going backwards at 2x times speed and I could see different parts of the recording jumping in and out. Very hard to find where to stop.

    Anything else I can try on my own?
     

    johnzered

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    Anything else I can try on my own?

    I suppose one thing you could try on your own is again test with 1.3 and make sure the error is not there and then test each version (1.4, 1.5 etc) until the error becomes present. Then it should at least be easier for the developers to nail down the problem when they know what version is the breaking one.
     

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