src/Godosa.Core/Audio/Pcm.cs


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using System;

namespace Godosa.Core.Audio;

/// <summary>16-bit mono PCM helpers.</summary>
public static class Pcm
{
    public const int SampleRate = 44100;

    /// <summary>Interleaved float frames (e.g. decoded OGG) → mono 16-bit.</summary>
    public static short[] Downmix(float[] interleaved, int channels)
    {
        var pcm = new short[interleaved.Length / channels];
        for (int f = 0; f < pcm.Length; f++)
        {
            float sum = 0f;
            for (int c = 0; c < channels; c++) sum += interleaved[f * channels + c];
            pcm[f] = ToShort(sum / channels);
        }
        return pcm;
    }

    public static short ToShort(float sample) => (short)Math.Clamp(MathF.Round(sample * short.MaxValue), -short.MaxValue, short.MaxValue);
}