Windows Media Audio and Video Codec and DSP APIs MFPKEY_WMRESAMP_CHANNELMTX Property 

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MFPKEY_WMRESAMP_CHANNELMTX Property

Specifies the channel matrix, which is used to convert the source channels into the destination channels (for example, to convert 5.1 to stereo).

Data Type

VT_I4 | VT_ARRAY

Remarks

The value of the property is a matrix of Ns x Nd coefficients, where Ns is the number of source channels and Nd is the number of destination channels. Coefficients are specified in decibels using the following formula:

(int)(65536*20*log10(dB))

The matrix is stored as an array in row-major order where the row number is the source channel and the column number is the destination channel.

Thus, if the matrix is the following:

00       01       ...      0(Ns-1)
10       11       ...      1(Ns-1)
...      ...      ...      ...
(Nd-1)0  (Nd-1)1  ...      (Nd-1)(Ns-1)

then you would specify the array as:

[ 00, 01, ..., 0(Ns-1), 10, 11, ..., 1(Ns-1), ..., (Nd-1)0, (Nd-1)1, ..., (Nd-1)(Ns-1) ]

Requirements

Client: Requires Windows Vista.

Header: Include wmcodecdsp.h.

See Also

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