D audio playing and analysis library?

[Stincky gecko via Digitalmars-d]

On Tuesday, 28 April 2015 at 15:49:53 UTC, ponce wrote:
> On Tuesday, 28 April 2015 at 15:11:16 UTC, Stincky gecko wrote:
>> On Tuesday, 28 April 2015 at 15:01:23 UTC, ponce wrote:
>>> On Tuesday, 28 April 2015 at 15:00:18 UTC, ponce wrote:
>>>> - clearing the state (setting delaylines to 0)
>>>> - separate channels that can be stored interleaved or not. 
>>>> Samples would be indexed by time and channel index. I feel 
>>>> like samplerate can be left out of the equation, it will 
>>>> almost always be a runtime value.
>>>
>>> - and more importantly, batch processing instead of sample per
>>> sample like I do now in dplug
>>
>> in d plug sample by sample processing is justified because of 
>> the z-transform, while in video games you just basically play 
>> some wavetables.
>
> Even hugely stateful things can benefit of buffering.
>
> For example, biquad filters have an internal loop that looks 
> like (pseudo-code):
>
>     for each sample
>     {
>         input <- input-signal[n]
>         output <- a0 * input + a1 * x[0] + a2 * x[1] - a3 * 
> y[0] - a4 * y[1]
>
>         // update state of filter
>         x[1] <- x[0]
>         x[0] <- input
>         y[1] <- y[0]
>         y[0] <- output;
>     }
>
> It cannot be parallelized because it's too stateful.
> BUT by unrolling it by 3, SIMD can be used and benefit such a 
> loop.

This is what i meant by z-transform, maybe a confusion in the 
name, but it think to "the fact that the previous sample value 
must be stored for processing the next one"...

If you have only a filter it can be batch-processed but if the 
the filter is plugged to a delay line itself pluged to a SSB 
frequency shifter whose itself has a feedback bus going to...well 
it cant be buffered anymore.

In video game, they play wavetables and eventually the output is 
passed in a binaural spatiializer or a reverb unit...though it's 
still need sample rate info for re-sampling and maybe dithering 
depending on the sample bit-depth of the samples frames.