[Openal] How to calculate duration of play in openal

[Daniel PEACOCK]

Hi Anand,

To compute the duration of a sample you need to know the byte length of the
audio data and the average bytes per second (and the playback pitch if it
not going to be equal to 1.0).

For a PCM wavefile, the average bytes-per-second is one of the parameters
in the wave header and the byte length of the audio data immediately
follows the 'data' RIFF ID chunk.

// dwDataSize is number of bytes of audio data
// nAvgBytesPerSec is the average bytes per second read from wave header
(or computed using SamplesPerSecond * Number of Channels * Bits Per Sample
/ 8)
// flPlayback pitch is the pitch parameter set on the Source (default is
1.0)

float flDurationSeconds = ((float)dwDataSize / nAvgBytesPerSec ) /
flPlaybackPitch;

NOTE : If you are using Doppler then that will affect the duration of
playback too ... and things get more complicated if you want to include
that in your calculations ;0)

Dan
Creative Labs, Inc.

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             anand                                                         
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                                       [Openal] How to calculate duration  
                                       of play in openal                   
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Hi All,

I am new to this openal can any one tell me how to calculate time duration
for audio file.well in core audio
Float64 fileDuration= (nPackets * fileFormat.mFramesPerPacket) /
fileFormat.mSampleRate;
this works. But how to calculate in openal:(
any help will be greatly appreciated.

Thanks in advance
-----------------
Anand



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