Q:
I'm trying to create MPEG-4 (.mp4), 3GPP (.3gp) and/or 3GPP2 (.3g2) format files on my Windows PC using the ConvertMovieToFile function. The resulting files always contain valid video, but no audio. No errors are being returned from this function. What am I doing wrong?
A: The AAC and AMR compressors that ship with QuickTime are only available to licensed applications via a private Software Development Kit (SDK) on Windows.
Therefore, you can't use any of the QuickTime movie exporter functions such as ConvertMovieToFile from your own application to encode audio to the AMR or AAC formats without first obtaining a license:
For AMR:
Contact VoiceAge for AMR licensing information.
Once the AMR patent license is obtained, contact Apple Software Licensing for the AMR SDK license. When contacting Apple Software Licensing please indicate that you are interested in the AMR SDK license and include a full company name, address and contact email address.
For AAC:
Contact Apple Software Licensing for the AAC SDK license. When contacting Apple Software Licensing please indicate that you are interested in the AAC SDK license and include a full company name, address and contact email address.
Note: You may encode audio to the AMR or AAC formats using QuickTime Pro on Windows without any restrictions.
On Macintosh, applications may create content with these formats without the requirements mentioned above.
Document Revision History
| Date |
Notes |
| 2009-03-16 |
Updated licensing requirements |
| 2007-04-13 |
Updated contact URL for Via Licensing Corporation |
| 2006-01-25 |
misc. changes |
| 2006-01-06 |
fixed broken link |
| 2004-05-20 |
minor wording changes |
| 2004-04-05 |
This QA discusses use of the QuickTime AMR and AAC audio compressors on Macintosh and Windows |
Posted: 2009-03-16
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