Hi Herbert, Hi Christoph,

> On Oct 9, 2020, at 12:33 PM, Herbert König <herbertkoenig at gmx.net> wrote:
> 
>  Hi Christoph,
> 
> maybe you hit upon a stereo representation with interleaved channels? But then it should be 16 bit words, so not sure.

That’s right.  The sound output primitive takes interleaved (alternating left/right, signed) 16-bit samples.  So the mix down methods mix from whatever the representation into this stereo representation.

> 
> Cheers,
> 
> Herbert
> 
> storeWAVSamplesOn: aBinaryStream
>     "Store this sound as a 16-bit Windows WAV file at the current SoundPlayer sampling rate. Store both channels if self isStereo is true; otherwise, store the left channel only as a mono sound."
> 
> Am 09.10.2020 um 18:19 schrieb Thiede, Christoph:
>> Hi all,
>> 
>> 
>> 
>> for a test, I am storing sounds into a ByteArray and read them again. This works well for PluckedSounds, for example, but I found some strange behavior when doing the same with SampledSounds:
>> 
>> 
>> 
>> sound := SampledSound new
>> setSamples: SampledSound coffeeCupClink
>> samplingRate: 12000.
>> 
>> bytes := ByteArray streamContents: [:stream |
>> sound storeWAVSamplesOn: stream].
>> 
>> outputSound := SampledSound fromWaveStream: bytes readStream binary.
>> 
>> 
>> After running this script, I would expect outputSound to have the same samples as sound. But actually, every byte in the SoundBuffer appears twice! Still, playing the sound does not sound differently in my ears. I traced the issue down and found out that #mixSampleCount:into:startingAt:leftVol:rightVol: is writing every byte four times on the stream - two would be okay for left and right channel, but I do not understand the four. I reproduced the issue both on Windows and Ubuntu (WSL). Disabling the primitive did not help either.
>> 
>> 
>> 
>> So I am wondering: Is this a bug or totally fine (because you cannot hear a difference anyway)? If the latter is the case, how can I compare the sounds else in a reliable way? If I store outputSound again, the number of bytes is doubled again, so if you do certain operations, your image will blow up exponentially ...
>> 
>> 
>> For the context of this question, see also: http://forum.world.st/Overriding-in-Graphics-and-Sounds-td5122783.html
>> 
>> Best,
>> Christoph
>> 
>> 
> 
> 
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