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Re: Offline Rendering... still a thing?
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Re: Offline Rendering... still a thing?

  • Subject: Re: Offline Rendering... still a thing?
  • From: Matthew Pease <email@hidden>
  • Date: Wed, 05 Aug 2015 09:39:42 +0200
Hi Brian -

  Thanks for writing back.  I was beginning to fear that AQ apis were dead & the world had moved on to something else.

  The reason I chose Offline rendering is because I'd like to get that metering data without playback.    Of course I could just mute the queue.   But I'd like to maybe be able to at the same time be playing another audio queue.  

  I suppose another way to do this might be to have two audio queues.  One of them fed with the Audio File Stream services network data.   The other audio queue doing the actual playback.

  The more detailed version is that I'd like to provide a Tivo style ability to seek in the recent history of a stream.  I want to display the entire history of the stream as graph of the levels.   So that the user can see where there is activity within the stream.  The app would allow them to quickly jump to some point in the history.

Thanks
Matt

On Wed, Aug 5, 2015 at 7:42 AM, Brian Willoughby <email@hidden> wrote:
Matt,

I'm a little confused about your exact goal. Metering is generally shown visually in real time, and I assume your mp3 stream is also real time, so I don't understand why you would be trying to work with offline rendering.

Assuming that you're converting the mp3 stream to audio as it arrives in real time, then you should be able to obtain level metering data from the Float32 audio stream that's being sent through CoreAudio.

Offline processing is for running through data faster than you can listen to it (or slower, if the processing is really heavy).

Brian Willoughby
Sound Consulting


On Aug 4, 2015, at 1:19 AM, Matthew Pease <email@hidden> wrote:
>  I'd like to obtain level metering data while the incoming mp3 stream arrives.  About 4 or 5 years back I asked this mailing list how to do this & the answer at that time was to use an offline render queue.  (actually my question at that time was about panning)
>
>   My idea then was to translate an incoming stream into a PCM file & obtain metering at the same time by using an offline queue.
>
>   I'm having lots of trouble getting this to work though .  The Offline render queue seems to be a black art.   Using the AQOfflineRenderTest as an example:  For example if you simply change the size of the capture buffer to 1/4 the input buffer, it no longer works.  But why??
>
>    Is the recommended way to do this still AQ offline rendering or is there an easier way?


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  • Follow-Ups:
    • Re: Offline Rendering... still a thing?
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      • From: Matthew Pease <email@hidden>
References: 
 >Offline Rendering... still a thing? (From: Matthew Pease <email@hidden>)
 >Re: Offline Rendering... still a thing? (From: Brian Willoughby <email@hidden>)

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