SpeechAudioFormatInfo.BlockAlign Property

Gets and sets the block alignment in bytes.

Namespace:  Microsoft.Speech.AudioFormat
Assembly:  Microsoft.Speech (in Microsoft.Speech.dll)

public int BlockAlign { get; }

Property Value

Type: System.Int32
An int containing the block alignment value.

Playback and record software handles audio data in blocks. The sizes of these blocks are multiples of the value of the BlockAlign property. Block alignment value is the number of bytes in an atomic unit (that is, a block) of audio for a particular format. For Pulse Code Modulation (PCM) formats, the formula for calculating block alignment is as follows:

  • Block Alignment = Bytes per Sample x Number of Channels

For example, the block alignment value for 16-bit PCM format mono audio is 2 (2 bytes per sample x 1 channel). For 16-bit PCM format stereo audio, the block alignment value is 4.

Data written and read from a device must always start at the beginning of a block. For example, it is illegal to start playback of PCM data in the middle of a sample (meaning on a boundary that is not block-aligned).