• December 02, 2020, 05:28:28 AM
  • Welcome, Guest
Please login or register.

Login with username, password and session length
Advanced search  

News:

This Forum Beta is ONLY for registered owners of D-Link products in the USA for which we have created boards at this time.

Author Topic: Fixing the audio out of synch with video problem in AVI's  (Read 5555 times)

lrackow

  • Level 1 Member
  • *
  • Posts: 7
Fixing the audio out of synch with video problem in AVI's
« on: April 23, 2009, 09:49:41 AM »

Some AVI files that play fine on the PC play with the audio out of synch with the video on the DSM-520.  Re-encoding the AVI files can fix this, but it is trial and error and each time yo do it can take a while and the video might be degraded.  I have found a program, Avidemux, that can fix these files in seconds.

Avidemux is a free video editor designed for simple cutting, filtering and encoding tasks. It supports many file types, including AVI, DVD compatible MPEG files, MP4 and ASF, using a variety of codecs. Tasks can be automated using projects, job queue and powerful scripting capabilities.  It is available at www.avidemux.org.

The issue appears to be that the AVI files use VBR (variable bit rate) MP3 audio.  The VBR time maps are not apparently stored in the AVI files, but are constructed on the fly when the AVI is played.  Using a 0.5+GB test AVI file that the DSM-520 played with the audio out of synch with the video, AVIDemux built the time map in 12 seconds and saved the new file in 33 seconds.  The video was not re-encoded so there was no video degradation.  The resulting file was only about 2KB larger.

To fix the audio synchronization in an AVI file:
1   Run AVIDemux 2.4GTK+ (more than one version is installed).
2   Drag and drop or load the subject file into Avidemux.
3   A dialog box will popup asking if you want to "Build VBR Time Map?"
4   Say Yes to Build Time Map.
5   When done, the next box will say "Packed Bitstream detected.  Do you want me to unpack it?"
6   Respond No.
7   Save the updated file.

The big question now is why can't the DLink Media Server/Media Lounge software do this on the fly?  That wouldn't even need an update to the firmware, which has been coming out any day now for the last year.

I tried this on a DVR-MS file.  The process would abort near the end of the run.  DLink's programmers can probably easily fix this, and again add this to the DLink Media Server/Media Lounge software and solve the DVR-MS file problem as well, again without updating the firmware.

What do you say DLink?
Logged

ECF

  • Poweruser
  • Level 11 Member
  • *
  • Posts: 2692
Re: Fixing the audio out of synch with video problem in AVI's
« Reply #1 on: May 01, 2009, 02:58:00 PM »

Thank you I will forward this to Product management to improve the D-Link Media server software and see what they think.
Logged
Never forget that only dead fish swim with the stream