android 整合 speex 实现降噪

要在 Android 应用中实现 Speex 的降噪功能，可以按照以下步骤进行：

1. 在项目的 build.gradle 文件中添加以下依赖：

dependencies {
    implementation 'org.xiph.speex:speex:1.2.0'
}

2. 实现降噪功能的代码如下：

import org.xiph.speex.*;

public class SpeexNoiseReduction {

    private final int FRAME_SIZE = 160;

    private final int SAMPLE_RATE = 8000;

    private final int WINDOW_SIZE = 128;

    private final float[] window = new float[WINDOW_SIZE];

    private final float[] in = new float[FRAME_SIZE];

    private final float[] out = new float[FRAME_SIZE];

    private final int[] noise = new int[FRAME_SIZE];

    private final int[] prior = new int[FRAME_SIZE];

    private final SpeexPreprocess preprocess = new SpeexPreprocess();

    public SpeexNoiseReduction() {
        preprocess.init(FRAME_SIZE, SAMPLE_RATE);
        preprocess.setNoiseSuppress((int) -25);
        preprocess.setEchoSuppress((int) -40);
        preprocess.setEchoSuppressActive(true);
        preprocess.setNoiseSuppressActive(true);
        for (int i = 0; i < WINDOW_SIZE; i++) {
            window[i] = (float) (0.54 - 0.46 * Math.cos(2 * Math.PI * i / (WINDOW_SIZE - 1)));
        }
    }

    public short[] process(short[] data) {
        int totalFrame = data.length / FRAME_SIZE;
        for (int i = 0; i < totalFrame; i++) {
            for (int j = 0; j < FRAME_SIZE; j++) {
                in[j] = window[j] * data[i * FRAME_SIZE + j];
            }
            preprocess.preprocess(in, null);
            preprocess.getNoises(noise, prior);
            for (int j = 0; j < FRAME_SIZE; j++) {
                out[j] = in[j] - noise[j];
            }
            for (int j = 0; j < FRAME_SIZE; j++) {
                data[i * FRAME_SIZE + j] = (short) out[j];
            }
        }
        return data;
    }
}

3. 在需要使用降噪功能的地方，创建 SpeexNoiseReduction 实例并调用 process() 方法即可，例如：

SpeexNoiseReduction speexNoiseReduction = new SpeexNoiseReduction();
short[] audioData = getAudioData();
short[] denoisedData = speexNoiseReduction.process(audioData);
// 使用 denoisedData 进行后续操作

注意：该示例代码仅供参考，请根据实际情况进行修改。