processBlock() [1/2]

void fl::audio::SoundLevelMeter::processBlock	(	const fl::i16 *	samples,
		fl::size	count )

Process a block of int16 PCM samples.

Definition at line 157 of file audio.cpp.hpp.

                                                                                  {
    if (count == 0) {
        return;
    }
 
    // 1) compute block power → dBFS
    double sum_sq = 0.0;
    for (fl::size i = 0; i < count; ++i) {
        double s = samples[i] / 32768.0; // normalize to ±1
        sum_sq += s * s;
    }
    double p = sum_sq / count; // mean power
    double dbfs = 10.0 * log10(p + 1e-12);
    mCurrentDbfs = dbfs;
 
    // 2) update global floor (with optional smoothing)
    if (dbfs < mDbfsFloorGlobal) {
        if (mDbfsFloorGlobal == FL_INFINITY_DOUBLE || mSmoothingAlpha <= 0.0) {
            mDbfsFloorGlobal = dbfs;
        } else {
            mDbfsFloorGlobal = mSmoothingAlpha * dbfs +
                                 (1.0 - mSmoothingAlpha) * mDbfsFloorGlobal;
        }
        mOffset = mSplFloor - mDbfsFloorGlobal;
    }
 
    // 3) estimate SPL
    mCurrentSpl = dbfs + mOffset;
}

References FL_INFINITY_DOUBLE, fl::FL_NO_EXCEPT, fl::log10(), mCurrentDbfs, mCurrentSpl, mDbfsFloorGlobal, mOffset, mSmoothingAlpha, and mSplFloor.

Referenced by processBlock().

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