COM Objects > ACM object > Methods > EncodeFormats.ACM.GetCodecFormatWavData method

Remarks

Obtains the WAVEFORMATEX data structure, which defines the format of waveform-audio data, that describes the format of the given ACM codec including any extra-byte the specific format may require.

The WAVEFORMATEX structure, common to all waveform-audio formats, is defined inside the Microsoft SDK as follows:

typedef struct {

WORD wFormatTag;

WORD nChannels;

DWORD nSamplesPerSec;

DWORD nAvgBytesPerSec;

WORD nBlockAlign;

WORD wBitsPerSample;

WORD cbSize;

} WAVEFORMATEX;

The cbSize member defines how many extra-bytes are appended to the end of the WAVEFORMATEX structure: the total size in bytes of the WAVEFORMATEX data structure that describes the given format, including any extra-byte the specific format may require, can be obtained using the EncodeFormats.ACM.GetCodecFormatWavDataLength method.

For further details about using the Windows Audio Compression Manager refer to the ACM object section.

For a tutorial about the use of the Windows Audio Compression Manager refer to the How to use the Windows Audio Compression Manager section.

For further information about available encoding formats see the EncodeFormats object.

Syntax

[Visual Basic]

control.EncodeFormats.ACM.GetCodecFormatWavData (

nCodecIndex as integer,

nCodecFormatIndex as integer,

pWavData as long,

sizeWavData as long

) as enumErrorCodes

[C++]

short control.EncodeFormats.ACM.GetCodecFormatWavData (

short nCodecIndex,

short nCodecFormatIndex,

void *pWavData,

long sizeWavData

);

Parameter	Description

nCodecIndex	Number representing the zero-based index of the ACM codec
nCodecFormatIndex	Number representing the zero-based index of the format for the given ACM codec
pWavData	Memory buffer that, on exit from the method's call, will contain the given codec's format description: this buffer should be allocated through a global variable in order to avoid becoming invalid when the variable will go out of scope.
sizeWavData	The size in bytes of the WAVEFORMATEX data structure, including any extra-byte the specific format may require: this parameter should be initialized using a previous call to the EncodeFormats.ACM.GetCodecFormatWavDataLength method

Return value

Value	Meaning

Negative value	An error occurred, check the LastError property value in order to get the error code
enumErrorCodes.ERR_NOERROR (0)	The method call was successful