Audio Device Conformance Templates
[The feature associated with this page, Windows Media Format 11 SDK, is a legacy feature. It has been superseded by Source Reader and Sink Writer. Source Reader and Sink Writer have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Source Reader and Sink Writer instead of Windows Media Format 11 SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The following table lists the device conformance templates and associated parameters for the Windows Media Audio 9 codec, or later.
| Template string | Bit rate range | Notes |
|---|---|---|
| "L1" | 64 Kbps 160 Kbps | This template is intended for constrained audio-only devices. |
| "L2" | <= 160 Kbps | This template corresponds to Class 4 in the Windows Media Audio porting kit, which supports the entire Windows Media Audio decoder implementation. |
| "L3" | <= 384 Kbps | This template corresponds to Class 4 in the Windows Media Audio porting kit, which supports the entire Windows Media Audio decoder implementation.The bit rate range is the only difference between this template and L2. |
| "L" | All bit rates | This template is for use with personal computers only, and is usually used to showcase the full capabilities of the codec. |
The following table lists the device conformance templates and associated parameters for the Windows Media Audio 9 Voice codec.
| Template string | Bit rate range | Notes |
|---|---|---|
| "S1" | <= 20 Kbps | This template is intended for very low-complexity devices only.This template is speech only. |
| "S2" | <= 20 Kbps | This is the recommended template for most applications.This template supports combinations of speech and music. |
The following table lists the device conformance templates and associated parameters for the Windows Media Audio 9 Professional codec, or later.
| Template string | Properties | Notes |
|---|---|---|
| "M1" | Bit rate <= 384 KbpsSampling rate <= 48 kHz Channels <= 5.1 |
This template is recommended for standard movies with surround sound. |
| "M2" | Bit rate <= 768 KbpsSampling rate <= 96 kHz Channels <= 5.1 |
This template is recommended for high-definition movies with surround sound. |
| "M3" | Bit rate <= 1,500 KbpsSampling rate <= 96 kHz Channels <= 7.1 |
This template is recommended for high-definition movies with 8-channel surround sound, such as content encoded for presentation in theaters. |
| "M" | All bit ratesAll sampling rates All channels |
This template is for use with personal computers only, and is usually used to showcase the full capabilities of the codec.This is also the template designation for all audio encoded with the Windows Media Audio 9 Lossless codec. |