The LEAD AC3 Audio Encoder Transform is a MediaFoundation® transform for compressing audio data using the AC3 compression standard (A/52 - Digital Audio Compression Standard (AC-3)). AC3 is the sound format for digital television (DTV), digital versatile discs (DVDs ), high definition television (HDTV), and digital cable and satellite transmissions. AC3 is a 5.1 format, which means that it provides five full-bandwidth channels, front left, front right, center, surround left, and surround right. A low-frequency effect (LFE) channel is included for the sound needed for special effects and action sequences in movies. AC3 also has a downmixing feature that ensures compatibility with devices that do not support the 5.1 format.
Key features of the LEAD AC3 Audio Encoder:
Can create Dolby Digital with 6-channel surround sound.
Can create DVDs with Dolby surround.
Convert a 2-channel input into a 6-channel output or encode 6-channels as is.
You can use the encoder with your existing converter or DVD creator application, if it allows you to select the audio encoder. The AC3 encoder supports unchanged audio input, Force Mono, Force Stereo or Force 6 Channels. This audio encoder is needed in order to create DVDs that have 5.1-channel surround sound.
The LEAD AC3 encoder implements the standard IMFTransform interface and compression options can be set as attributes on the transform's output media type.
The compression options for the LEAD AC3 encoder can also be set programmatically using the ILMFAC3Encoder interface.
Technical details for the transform are provided in the following table:
Transform Interfaces |
ILMFAC3Encoder, IMFTransform |
Interface ID | IID_ILMFAC3Encoder |
Input Media Types |
Type: |
Output Media Types |
Type: |
Transform CLSID |
CLSID_LMFAC3Encoder |
Property Page CLSID |
N/A. |
Executable |
LEncMFAC3.dll |
Transform category |
MFT_CATEGORY_AUDIO_ENCODER |
Header |
ILMFEncAC3.h |
Win 32, x64