COM Objects > SoundComposer object > Methods > SoundComposer.ItemSoundFileMemoryAdd method

Remarks

Adds a sound stored inside a memory buffer, or a given range within the sound, to the audio stream previously created through the SoundComposer.SessionCreate method. Supported sound file formats are the same mentioned inside the LoadSound method.

In case the sound file should be stored inside a file on disk use the SoundComposer.ItemSoundFileAdd method.

In case the sound file should be in a RAW format use the SoundComposer.ItemSoundFileRawAdd or SoundComposer.ItemSoundFileMemoryRawAdd methods.

IMPORTANT NOTE: Items added through this method will not be saved into the destination XML file when the SoundComposer.SessionSave method is invoked.

For further details about sound composing see the the SoundComposer object and the How to compose a sound tutorial.

Syntax

[Visual Basic]

control.SoundGenerator.ItemSoundFileMemoryAdd (

nPlayer as Integer,

strFriendlyName as String,

nChannel as Integer,

pBuffer as Variant,

nBufferLength as Long,

bDownMixToMono as enumBoolean,

nOffsetMs as Long,

nStartPositionMs as Long,

nEndPositionMs as Long,

ByRef nUniqueId as Long

) as enumErrorCodes

[C++]

short control.SoundGenerator.ItemSoundFileMemoryAdd (

short nPlayer,

LPCTSTR strFriendlyName,

short nChannel,

const VARIANT FAR& pBuffer,

long nBufferLength,

short bDownMixToMono,

long nOffsetMs,

long nStartPositionMs,

long nEndPositionMs,

long *nUniqueId

);

Parameter

Description

nPlayer

Number representing the zero-based index of the player that owns the sound composer session

strFriendlyName

Friendly name of the item

nChannel

Mono channel or stereo channel pair of the audio stream that will reproduce the item.

This parameter is ignored when the sound file is added in "append mode" after a previous call to the SoundComposer.ItemAppendNext method.

Due to the fact that the audio stream previously created through the SoundComposer.SessionCreate method could be multi-channel, this would be the behaviour when a sound file item is added:

•	if the sound file has one single channel (Mono) or two channels (Stereo), its mapping on the audio stream would be in two possible ways:

•	if the bDownMixToMono parameter is set to "true" the sound file is downmixed to mono and mapped on the audio stream inside the channel identified by the nChannel parameter

•	if the bDownMixToMono parameter is set to "false" the nChannel parameter, instead of representing the index of a mono channel, represents the index of the stereo channel pair (*) on which the sound file item is mapped: for Mono sound files the stream will be duplicated on both channels.

•	if the sound file has more than two channels (multi-channel), its mapping on the audio stream would be in two possible ways:

•	if the bDownMixToMono parameter is set to "true" the sound file is downmixed to mono and mapped on the audio stream inside the channel identified by the nChannel parameter

•	if the bDownMixToMono parameter is set to "false" the sound file is in any case downmixed to stereo and the nChannel parameter, instead of representing the index of a mono channel, represents the index of the stereo channel pair (*) on which the sound file item is mapped.

(*) If for example the audio stream previously created through the SoundComposer.SessionCreate method should have 8 channels (7.1 multi-channel), stereo channels pairs would be mapped as follows:

- stereo channel pair 0 would group mono channels 0 and 1

- stereo channel pair 1 would group mono channels 2 and 3

- stereo channel pair 2 would group mono channels 4 and 5

- stereo channel pair 3 would group mono channels 6 and 7

pBuffer

Input buffer containing the original sound

nBufferLength

Length of the input buffer expressed in bytes

bDownMixToMono

Boolean flag specifying if there is the need of a downmix in order to store a stereo sound file into a mono channel of the stream.

Supported values are the following:

Mnemonic Value	Meaning
false	Keep stereo channels separated
true	Downmix stereo channels to mono

This parameter is ignored when the sound file is added in "append mode" after a previous call to the SoundComposer.ItemAppendNext method.

nOffsetMs

Offset of the item, expressed in milliseconds, respect to the beginning of the audio stream (in case the stream should be in stopped state) or respect to the current playback position (in case the stream should be already in playback state).

This parameter is ignored when the sound file is added in "append mode" after a previous call to the SoundComposer.ItemAppendNext method.

nStartPositionMs

The start position, expressed in milliseconds, where the sound file loading will occur. Set this value to 0 for loading from the beginning of the sound.

nEndPositionMs

The end position, expressed in milliseconds, where the sound file loading will occur. Set this value to -1 for loading till the sound end.

nUniqueId

Reference to a value that, on return from the method call, will contain the unique identifier of the newly added element: this unique identifier will be used in order to invoke further methods related to the use of this specific element:

- SoundComposer.ItemFriendlyNameGet to obtain the friendly name of the item

- SoundComposer.ItemFriendlyNameSet to obtain the friendly name of the item

- SoundComposer.ItemContentGet to obtain contents of the item

- SoundComposer.ItemInfoGet to obtain various information about the item

- SoundComposer.ItemAmplitudeSet to modify the amplitude of the item

- SoundComposer.ItemChannelSet to modify the channel of of the audio stream that will reproduce the item

- SoundComposer.ItemRemove to remove the item from the sound composition

- SoundComposer.ItemOffsetSet to modify the offset, expressed in milliseconds, of the item respect to the beginning of the audio stream

- SoundComposer.ItemTypeGet to obtain the item's type

Return value

Value	Meaning

Negative value	An error occurred (see the LastError property for further error details)
enumErrorCodes.NOERROR (0)	The method call was successful.