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jriker1
25th December 2013, 21:58
I have a bunch of MKV files I am trying to convert to WMV as my entire house is wired with Xbox units and Windows Media Center. Xbox doesn't play 5.1 audio unless the source is WMV. Problem I'm having is some audio sources loose sync especially when converting DTS. So an example all specs taken from MediaInfo:

Source Film:
Video source: 6949157 or 1h 55mn 49s 157ms
Audio source: 6949152 or 1h 55mn 49s 152ms

Slightly off by 5ms but not sure that matters.

Extracted DTS file with mkvextract has no duration info for some reason but here are it's specs:

Commercial name : DTS
Format profile : MA / Core

Bit rate : Unknown / 1509000
Bit rate : Unknown / 1 509 Kbps
Channel(s) : 8 / 6
Channel(s) : 8 channels / 6 channels

I then convert it to AC3.

Convert to AC3:
Audio Source: 6949024 or 1h 55mn 49s 24ms

Seems to be a bit more off from the source.

Then convert to WMA to be encapsulated in a WMV with the video file also now WMV but all durations match the original.

WMV:
Video source: 6949157 or 1h 55mn 49s 157ms
Audio source: 6949042 or 1h 55mn 49s 42ms

Seems like the audio got a bit longer again. Now with this video, it usually plays in sync but occasionally on the Xbox thru the Windows Media Center looses sync about 2/3 thru the movie. Guessing it has something to do with the conversion process but not sure.

Thoughts knowing I need to have this in WMV final format?

As a side note, tried using eac3to to convert to mono wav files and softencode to ac3. Resulting wav and subsequent ac3 were slightly over 2 hours compared to the video being 15 55mn.

Thanks.

JR

jriker1
26th December 2013, 01:26
just for reference I was able to use some commands in eac3to (-core -slowdown) in order to go after the core and save those to a regular DTS. Then took that DTS file in eac3to and exported 6 wav files. The resulting DTS file showed me the same file length as the original. The resulting WAV files also did. If I put them into an ac3 file it also shows the same length contrary to the methods I usually use.

Challenge now when I put the ac3 thru Expression Encoder 4 to create a WMA file, the length of the resulting WMA is actually exactly what the WMA was in my original post. So although I was able to maintain the exact length of the original thru the process this time, the final file was off. Is there an alternative way to convert the WAV files to WMA or the resulting AC3 to WMA other than Expression Encoder? Would think being a MS product it would be the best choice but not sure.

filler56789
26th December 2013, 04:59
Is there an alternative way to convert the WAV files to WMA or the resulting AC3 to WMA other than Expression Encoder?

Yes, there is the old Windows Media Encoder 9.
Also, the small program WmNicEnc (requires Avisynth files for input).

And IMHO, the actual problem is not "MKV Audio",
the real problem is WMA && WMC && Xbox :sly:

jriker1
26th December 2013, 06:51
Tried something else. Remember my original audio in DTS HD was:

1h 55mn 49s 152ms

Tried TMPG Master Works 5. Took the AC3 and output to WMA. Audio output was:

1h 55mn 49s 205ms

Didn't see an option to try my 6 mono wav files to WMA to see what it would do but thinking the same.

I have Media Encoder 9 but thought it couldn't do 5.1 conversion without command line which doesn't work on Win 7 64-bit. At least that's what I read.

And be nice to my Xbox even though Microsoft discontinued their encoder and the new Xbox One got rid of most of the features I liked about it for streaming my content and being an extender. :)

jriker1
26th December 2013, 17:08
Tried WMEnc. Ended up with a video of using the DTS Core file in AVISynth:

1h 55mn 49s 194ms

Tried WMEnc with 5 separate wav files merged in AVISynth script and came to same size in MediaInfo

If I took one of those WAV files that has the correct duration down to the millisecond and convert with Windows Media Encoder 9 to WMA, it comes out a millisecond off which is good I think. Problem is I don't know how to create a single WMA from all five wav files in WME. Apparently Nic's encoder isn't using it as it came out with different timing. I'd even be interested if there is a way to take 6 separate WMA files and merge them into a single WMA file.

Oh and by the way when I take the separate WAV files and put them into an AVI using a tool MS came up with and then convert it to 5.1 in WME 9 I get the same ending in 194ms output.

Thanks.