Microsoft AC-3 Encoder
[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The Microsoft AC-3 Encoder filter encodes stereo PCM audio to a Dolby Digital bitstream.
Note
The Microsoft implementation of the Dolby Digital technology is restricted under terms of the Dolby Digital licensing program to use by Microsoft applications.
Note
This filter is not supported on IA-64-based platforms.
Filter Information
Filter Interfaces
Input Pin Media Types
MEDIATYPE_Audio, MEDIASUBTYPE_PCM
The input type must be 48-kHz stereo, 16 bits per sample.
Input Pin Interfaces
IMemInputPin
IPin
IQualityControl
Output Pin Media Types
MEDIATYPE_Audio, MEDIASUBTYPE_DOLBY_AC3
MEDIATYPE_Stream, MEDIASUBTYPE_DOLBY_AC3
Output Pin Interfaces
IMediaSeeking
IPin
IQualityControl
Filter CLSID
CLSID_CMSAC3Enc (declared in wmcodecdsp.h)
Executable
msac3enc.dll
MERIT_DO_NOT_USE
CLSID_LegacyAmFilterCategory
Remarks
This filter is not available for use by third-party applications.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client |
Windows Vista Home Premium, Windows Vista Ultimate, Windows 7 Home Premium, Windows 7 Professional, Windows 7 Enterprise, Windows 7 Ultimate [desktop apps only] |
| Minimum supported server |
None supported |
| Header |
|
See also