Class AudioEffects

java.lang.Object
com.codename1.media.AudioEffects
public final class AudioEffects extends Object

Small PCM effects that operate on AudioBuffer data.

The methods in this class are platform-neutral and work on interleaved normalized float PCM samples in the [-1, 1] range. They return new AudioBuffer instances and leave the source buffer unchanged.

  • Method Details

    • isSimdOptimizationsEnabled

      public static boolean isSimdOptimizationsEnabled()

      Indicates whether AudioEffects should use SIMD-backed kernels when the current platform supports them. Scalar fallbacks are always used for effects whose stateful filters don't map to the current SIMD API.

      Returns

      true when SIMD optimizations are enabled.

    • setSimdOptimizationsEnabled

      public static void setSimdOptimizationsEnabled(boolean enabled)

      Enables or disables SIMD-backed AudioEffects optimizations.

      This only changes internal implementation choices. It doesn't change output format or API behavior.

      Parameters
      • enabled: true to use SIMD where supported, false to force scalar loops.

    • resetSimdOptimizationsEnabled

      public static void resetSimdOptimizationsEnabled()
      Restores the default SIMD optimization setting for this platform.

    • gain

      public static AudioBuffer gain(AudioBuffer source, float gain)

      Applies gain to a PCM buffer.

      Parameters
      • source: The source buffer.
      • gain: Gain multiplier. 1.0f preserves level.
      Returns

      a new buffer with gain applied and samples clipped to [-1, 1].

    • normalize

      public static AudioBuffer normalize(AudioBuffer source, float targetPeak)

      Normalizes a PCM buffer so its largest absolute sample reaches targetPeak.

      Parameters
      • source: The source buffer.
      • targetPeak: Desired peak amplitude in the range [0, 1].
      Returns

      a new normalized buffer. Silent buffers are returned unchanged.

    • equalize

      public static AudioBuffer equalize(AudioBuffer source, float lowGain, float midGain, float highGain)

      Applies a simple three-band equalizer using default crossover points.

      Low frequencies are shaped below roughly 250 Hz, high frequencies above roughly 4 kHz, and the middle band contains the remaining signal.

      Parameters
      • source: The source buffer.
      • lowGain: Gain for the low band.
      • midGain: Gain for the middle band.
      • highGain: Gain for the high band.
      Returns

      a new equalized buffer clipped to [-1, 1].

    • equalize

      public static AudioBuffer equalize(AudioBuffer source, float lowGain, float midGain, float highGain, float lowCutoffHz, float highCutoffHz)

      Applies a simple three-band equalizer.

      This is intended for lightweight tone shaping and demos, not as a mastering-grade parametric equalizer.

      Parameters
      • source: The source buffer.
      • lowGain: Gain for samples below lowCutoffHz.
      • midGain: Gain for samples between the crossover bands.
      • highGain: Gain for samples above highCutoffHz.
      • lowCutoffHz: Low/mid crossover frequency.
      • highCutoffHz: Mid/high crossover frequency.
      Returns

      a new equalized buffer clipped to [-1, 1].

    • removeCenter

      public static AudioBuffer removeCenter(AudioBuffer source)

      Reduces center-panned content in a stereo buffer.

      This is the classic mid/side "vocal remover" technique. It only works when the content to remove is centered and similar in both channels.

      Parameters
      • source: A stereo source buffer.
      Returns

      a new stereo buffer with the center channel reduced.

    • isolateCenter

      public static AudioBuffer isolateCenter(AudioBuffer source)

      Isolates center-panned content in a stereo buffer.

      This can be useful for centered dialog or vocals, but it isn't true speech separation. It preserves only content common to the left and right channels, so it requires a stereo source where the target content is actually centered.

      Parameters
      • source: A stereo source buffer.
      Returns

      a new stereo buffer containing the center component.

    • midSide

      public static AudioBuffer midSide(AudioBuffer source, float midGain, float sideGain)

      Applies mid/side processing to a stereo buffer.

      Use a larger midGain and smaller sideGain for simple voice/dialog enhancement, or midGain=0 and sideGain=1 for center removal.

      Parameters
      • source: A stereo source buffer.
      • midGain: Gain for content common to left and right channels.
      • sideGain: Gain for content that differs between channels.
      Returns

      a new stereo buffer.