WMV -> MP4 sync issues

Entity · Post by **Entity** » Mon May 12, 2008 6:02 am

I've read about this but haven't seen any posts in the past month or two with any suggestions, so if it's still a bug please let me know. I'm converting WMV files right now using this preset: http://www.roadtorobusto.com/mediacoder/preset.xml and for some reason, there is a slight delay in the MP4 files that I create. It's nothing huge but is definitely an annoyance. I've included two samples to show the delay:

http://www.roadtorobusto.com/mediacoder/Untitled.wmv
http://www.roadtorobusto.com/mediacoder/Untitled.mp4

http://www.roadtorobusto.com/mediacoder/Untitled2.wmv
http://www.roadtorobusto.com/mediacoder/Untitled2.mp4

I've tried a bunch of settings including adding -vf harddup and -mc 0 -noskip to mencoder, but I can't seem to be able to get these to sync properly. Any ideas?

Rob

Entity · Post by **Entity** » Mon May 12, 2008 6:16 am

FWIW, I've also tried setting the encoder to FFMPEG, and it just resulted in the same problem (with a larger filesize). When I've changed "Source" to FFmpeg in either the audio or video areas, I get the message "Failed to load FFmpeg. This is possible that the decoder is absent or it doesn't support the specified file." I get this even after installing the additional codecs.

Rob

Entity · Post by **Entity** » Mon May 12, 2008 7:53 am

Ok -- so a bit more info. Sorry for the flood of posts but every hour it seems like I find a bunch of new info.

So, when the production settings are using audio wmav2 (WM10 audio professional) @ 48kbps in the WMV, I get the LAG (only in MP4, not in WMV).

When I produce the file using WMA 9.2 (WMAV2), I get no LAG in the MP4 but am unable to produce the file as an HE-AACV2. I've posted a screenshot of this here:

For the time being I'm just going to stop trying to produce the HE-AACV2 files and only produce the WMV files in WM9.2 until I can figure this one out -- if you guys have any ideas I would be very appreciative.

Here are the demo files I have that show this problem:

http://www.roadtorobusto.com/mediacoder/WM9.wmv

http://www.roadtorobusto.com/mediacoder/WM9.mp4

http://www.roadtorobusto.com/mediacoder/WM10.wmv

http://www.roadtorobusto.com/mediacoder/WM10.mp4

Miracle · Post by **Miracle** » Sun May 18, 2008 4:39 pm

Hi

I have the same problem. A bit diferent but same audio issues:)
I think i have the problems solution:) But a question too:D

I have a file:
Container: ASF
Bitrate: 1539 kbps
Duration: 2478 sec
Size 454MB
Overhead: 0,4%

Video: Vmv9dmo
Bitrate: 1453kbps
Resolution: 704x390
Framerate: 23,98
Audio: wma9dmo
Bitrate 79Kbps
Semple rate: 48000HZ
Channel: 2

I would like to convert it to xvid so i can watch this on my dvd player.
The problem is i think is the bitrate.
Every time i see its diferent i set the bitrate to 1453 kbps for conversion but in the statistic window its 1309kbps. So the bitrate i gave in is not relevant. I use bitrate based mode and the bitrate is not correct! How? The audio is good its in sync with the real file but on the copy its late about 1 sec. And becouse the bitrate its worse at the end.
How can i set the bitrate on xvid encoding so that it sticks to the rate i gave in and not something else?

Thx
Miracle

Intolerant of EVIL · Post by **Intolerant of EVIL** » Tue May 20, 2008 7:04 am

have you tried changing the "source" in both the audio and video tabs?

bobijam · Post by **bobijam** » Thu Jul 24, 2008 2:28 pm

Miracle wrote:Hi

The problem is i think is the bitrate.
Every time i see its diferent i set the bitrate to 1453 kbps for conversion but in the statistic window its 1309kbps. So the bitrate i gave in is not relevant. I use bitrate based mode and the bitrate is not correct! How? The audio is good its in sync with the real file but on the copy its late about 1 sec. And becouse the bitrate its worse at the end.
How can i set the bitrate on xvid encoding so that it sticks to the rate i gave in and not something else?

exactly same issue here (MediaCoder 0.6.1.4140), I set audio bitrate to 64 Kbps,
console window showed
"".\codecs\neroAacEnc.exe" -br 64000 -hinttrack -ignorelength -if - -of "Z:\tmp\mcstream8.aid0m4a"

after conversion finished, the console window told me
"FAAD: compressed input bitrate missing, assuming 128kbit/s!"

and when mplayer played this conversed video, it shows
"AUDIO: 44100 Hz, 2 ch, s16le, 128.0 kbit/9.07% (ratio: 16000->176400)"