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Converting Freeview files - Audio sync

Apr 14, 2013 at 2:15 AM
Hi

I'm new to MCEBuddy but have spent some time reading the documentation

I am having problems converting .WTV files containing content from UK Freeview channels.

The first problem is audio sync. I have had this problem when using other software to try and convert these files, basically the audio drifts further out of sync as the file plays, so if it is in sync at the beginning it might .5 secs out at 50% and 1 sec at 100%. As the error accumulates, I can't delay the audio as it not a fixed amount.

I have tried extending the -ss value but it hasn't made any difference on my test files.

I did find on a non WTV mpeg-2 file (using other software) that using CBR for the audio significantly reduced the problem and in some cases got rid of it, I've tried creating a new profile using

libmp3lame -ab 128k

which as I far as I can find should be cbr but when I check the file info it is still reported as VBR

Any ideas?
Coordinator
Apr 14, 2013 at 4:15 PM
What profile are you using? The vbr may be referring to the video.

Have you tried different encoders like handbrake instead of mencoder?

Apr 14, 2013 at 6:17 PM
I am using the three DIVX profiles plus a test profile based on the DIVX AVI Normal where I have changed the audio to lame as in previous post, it's definitely the audio that is reported as VBR, I am loading the file into VirualDub and it is reporting it.

I'll try some other decoders and see if the problem is consistent.
Coordinator
Apr 14, 2013 at 11:29 PM
are you facing the same issue with say the Apple Fast profile?


Apr 15, 2013 at 6:01 PM
I tried it this afternoon video looked OK but no audio at all on the file!

However, I found the following produced a CBR audio no apparent sync issue on the files I have tested so far

mencoder-audio=-oac mp3lame -lameopts cbr=yes:br=128

The downside is that it is taken forever to convert the video, probably 4-5 times what it is in VirtualDub.
Coordinator
Apr 15, 2013 at 7:18 PM
speed and time for encoding depends up on the profile you're using, it can make a 8-10x difference in the time taken depending upon the options used and your processor. I would reccomend start with the MP4 Normal or MP4 Fast profile as the base profile and then make your edits to it.


Apr 25, 2013 at 4:48 AM
Edited Apr 25, 2013 at 5:17 AM
I am also having audio sync issues with DVR-MS files converting to MP4 High Quality. I haven't messed with any special settings, just left the defaults.
Multichannel audio and DRC are checked.

By the way I am not in the UK.

I was going to try running the Fast & Normal profiles, just wanted to try and get the best possible quality. I'll try running it without the Multichannel audio and DRC.

Would it make any difference if I also have multiple recordings happening in WMC while I'm converting files with MCE Buddy, and potentially watching a show all at the same time.

Let me know if you have any ideas.

Thanks for your time.

Not sure if any of this makes a difference:
I'm running the 64-bit version
On an Intel i3-2120T 2.60GHz
8GB Ram
Windows 7 Ultimate SP1
Coordinator
Apr 25, 2013 at 2:19 PM
Multiple conversions and watching have no effect in the conversions.

If the audio is out of sync try using the Audio offset option to bring it back into sync.

Apr 25, 2013 at 3:36 PM
Okay I'll give that a try!

-Michael