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Re: Creating audio files
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Re: Creating audio files


  • Subject: Re: Creating audio files
  • From: Brian Willoughby <email@hidden>
  • Date: Mon, 9 Feb 2009 12:00:14 -0800

I believe that you would need to write your own audio file parsing and writing code. It is possible to append to an AIFF or WAV file if you scan it first, save any chunks which may be present after the audio chunk, seek to the end of the audio chunk, write your data, and then make sure that your code goes back and updates the sound chunk size, the total frames (where applicable), the total file size, and don't forget to write out the chunks which you saved because they come after the sound chunk. If you read the AIFF specification, you'll see that preserving chunks after editing a file can be tricky if you do not know the contents of each chunk - particularly whether the contents would be invalidated by adding more audio.

There is also the problem that appending to an existing file is riskier than recording to a new file and using some non-real-time technique to concatenate the two recordings.

Doing the same thing with MP3 or other formats would involve different challenges, but perhaps some aspects would be easier.

You could also create a meta-list which references several files in one timeline as if they were appended one after the other. This way, you could use existing AudioFile services without the need to append to existing files.

Brian Willoughby
Sound Consulting


On Feb 9, 2009, at 02:35, Mahaboob wrote:
I'm using a table view to show all the audio files. When I'm selecting one
file among these and click on the record button, the newly recording sound
should be attached to the end of the selected file.


So is there any way to create audio file without erasing the existing file?

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References: 
 >Creating audio files (From: Mahaboob <email@hidden>)

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