Skip to main content
Skip table of contents

Using AAC MP4 audio codecs

Since Release Cycle 2011.2, many DAVID applications support the handling (and in some case; playback) of AAC audio codecs.
This requires a current Audio32.dll and placing these codec files on the local hard disk:

- mc_dec_aac.dll
- mc_demux_mp4.dll
- mc_enc_aac.dll
- mc_mux_mp4.dll

The files must be inside the application path or included in Windows Path variable.
The *.ax DirectShow filter files must be registered using RegSvr32.exe

These applications can read and write MP4 formats; DBM, AudioEditors, DigAlign, DigaPorter.

DigaPorter and DigaTransfer require the current version of Audio32.dll inside the application folder (DBM, AudioEditors and DigAlign current versions do not).
DigaPorter must be configured by usage of section strings. The MP4 format is not available from the dropdown lists. The section strings must be entered into the field for advanced options and can look like this:


The full syntax can be taken from the documentation of Audio32.dll which is available on the Transfer Portal or from Support.

Please note that this feature requires licenses for the MainConcept codecs. You should contact our sales department first to learn about using these codecs.

Here's the excerpt from our 2011.2.0 Release Notes:

New Features:

The DLL now supports MP4-AAC formats for reading and writing.

Creation of AAC (Advanced Audio Coding) files, either “raw” or embedded in an MPEG-4 container is supported.

Audio32.dll uses MainConcept DLLs for AAC-encoding and MPEG4-muxing. These have to be installed to activate this feature and are part of the Audio32.dll package.



  • Copy audio32.dll into your DigaSystem directory
  • Copy required MainConcept MP4 filters and into the DigaSystem folder (all files in folder “MPEG4-AAC-Codecs”)
  • Register the two files and using regsvr32.exe


Conversion from and to MP4-AAC is supported using DigaPorter, DigAlign, DigaTransferSystem
(please refer to Audio32-documentation for format string)

For the use of DigaPorter the new option "Advanced Audio formats" setting must be set in “Converter Audio” section to configure format strings

Also successfully tested was an audio extraction from MP4-H264 video to broadcast audio (linear, mp2) using the audio32

Automated transcoding with Database Manager (DBM) – if auto-conversion is configured for a table an MP4-AAC file could be dropped into DBM and auto-conversion converts in the pre-defined format

This works only for MP4-AAC as source format! Creation of MP4 files using D&D operations is currently not supported (requires changes within DBM code)

JavaScript errors detected

Please note, these errors can depend on your browser setup.

If this problem persists, please contact our support.