OpenCVForUnity模糊与锐化

今次展示OpenCVForUnity插件中，模糊与锐化的处理。演示了比较多不同的算子，代码量看起来比较多。先来搭建一个简单的调试场景，用Toggle切换，可以直观地比较效果。

噪声

// 椒盐噪声
void OnSalt(bool value)
{
    m_blurImage.enabled = true;
    if (!value) return;

    //这里仅写了单通道例子
    Mat dstMat = new Mat();
    Imgproc.cvtColor(srcMat, dstMat, Imgproc.COLOR_RGB2GRAY); //转灰度
    int number = 500;
    byteArray = new byte[dstMat.width() * dstMat.height()];
    Utils.copyFromMat<byte>(dstMat, byteArray); //单通道

    for (int k = 0; k < number; k++)
    {
        int i = UnityEngine.Random.Range(0, dstMat.cols());
        int j = UnityEngine.Random.Range(0, dstMat.rows());
        byteArray[i + dstMat.width() * j] = 255;
    }
    Utils.copyToMat<byte>(byteArray, dstMat);

    Texture2D t2d = new Texture2D(dstMat.width(), dstMat.height());
    Sprite sp = Sprite.Create(t2d, new UnityEngine.Rect(0, 0, t2d.width, t2d.height), Vector2.zero);
    m_blurImage.sprite = sp;
    m_blurImage.preserveAspect = true;
    Utils.matToTexture2D(dstMat, t2d);
}

模糊

//简单模糊
void OnSimpleBlur(bool value)
{
    m_blurImage.enabled = true;
    if (!value) return;

    Mat dstMat = new Mat();
    dstMat = srcMat.clone();
    Size kSize = new Size(10d, 10d);
    Imgproc.blur(dstMat, dstMat, kSize);

    Texture2D t2d = new Texture2D(dstMat.width(), dstMat.height());
    Sprite sp = Sprite.Create(t2d, new UnityEngine.Rect(0, 0, t2d.width, t2d.height), Vector2.zero);
    m_blurImage.sprite = sp;
    m_blurImage.preserveAspect = true;
    Utils.matToTexture2D(dstMat, t2d);
}

//高斯模糊
void OnGaussianBlur(bool value)
{
    m_blurImage.enabled = true;
    if (!value) return;

    Mat dstMat = new Mat();
    dstMat = srcMat.clone();
    //高斯半径（σ）对曲线形状的影响
    //σ越小，曲线越高越陡峭，模糊程度越小。
    //σ越大，曲线越低越平缓，模糊程度越大。
    Size kSize = new Size(7d, 7d);
    double sigmaX = 2d;
    double sigmaY = 2d;
    Imgproc.GaussianBlur(dstMat, dstMat, kSize, sigmaX, sigmaY);

    Texture2D t2d = new Texture2D(dstMat.width(), dstMat.height());
    Sprite sp = Sprite.Create(t2d, new UnityEngine.Rect(0, 0, t2d.width, t2d.height), Vector2.zero);
    m_blurImage.sprite = sp;
    m_blurImage.preserveAspect = true;
    Utils.matToTexture2D(dstMat, t2d);
}

//中值模糊
void OnMedianBlur(bool value)
{
    m_blurImage.enabled = true;
    if (!value) return;

    Mat dstMat = new Mat();
    dstMat = srcMat.clone();
    int kSize = 7;
    //用像素点邻域灰度值的中值来代替该像素点的灰度。
    Imgproc.medianBlur(dstMat, dstMat, kSize);

    Texture2D t2d = new Texture2D(dstMat.width(), dstMat.height());
    Sprite sp = Sprite.Create(t2d, new UnityEngine.Rect(0, 0, t2d.width, t2d.height), Vector2.zero);
    m_blurImage.sprite = sp;
    m_blurImage.preserveAspect = true;
    Utils.matToTexture2D(dstMat, t2d);
}

//双边滤波
void OnBilateralFilter(bool value)
{
    m_blurImage.enabled = true;
    if (!value) return;

    Mat dstMat = new Mat();
    dstMat = srcMat.clone();
    int d = 25;
    double sigmaColor = 50d;
    double sigmaSpace = 35d;
    Imgproc.bilateralFilter(srcMat, dstMat, d, sigmaColor, sigmaSpace);

    Texture2D t2d = new Texture2D(dstMat.width(), dstMat.height());
    Sprite sp = Sprite.Create(t2d, new UnityEngine.Rect(0, 0, t2d.width, t2d.height), Vector2.zero);
    m_blurImage.sprite = sp;
    m_blurImage.preserveAspect = true;
    Utils.matToTexture2D(dstMat, t2d);
}

锐化

//简单锐化
void OnSimpleSharpen(bool value)
{
    m_blurImage.enabled = true;
    if (!value) return;

    Mat dstMat = new Mat();
    Mat kernel = new Mat(3, 3, CvType.CV_32F, new Scalar(-1));
    kernel.put(0, 0, 0, -1, 0, -1, 5, -1, 0, -1, 0);
    //对图像srcMat和自定义核kernel做卷积，输出到dstMat
    Imgproc.filter2D(srcMat, dstMat, srcMat.depth(), kernel);

    Texture2D t2d = new Texture2D(dstMat.width(), dstMat.height());
    Sprite sp = Sprite.Create(t2d, new UnityEngine.Rect(0, 0, t2d.width, t2d.height), Vector2.zero);
    m_blurImage.sprite = sp;
    m_blurImage.preserveAspect = true;
    Utils.matToTexture2D(dstMat, t2d);
}

//索贝尔算子锐化
void OnSobelSharpen(bool value)
{
    m_blurImage.enabled = true;
    if (!value) return;

    Mat dstMat = new Mat();
    Mat dst_x = new Mat();
    Mat abs_dst_x = new Mat();
    Mat dst_y = new Mat();
    Mat abs_dst_y = new Mat();

    //水平方向梯度
    Imgproc.Sobel(srcMat, dst_x, srcMat.depth(), 1, 0, 3, 1, 0);
    //垂直方向梯度
    Imgproc.Sobel(srcMat, dst_y, srcMat.depth(), 0, 1, 3, 1, 0);

    Core.convertScaleAbs(dst_x, abs_dst_x); //先缩放元素再取绝对值
    Core.convertScaleAbs(dst_y, abs_dst_y);
    Core.addWeighted(abs_dst_x, 0.5d, abs_dst_y, 0.5d, 0, dstMat); //x,y方向梯度，平均叠加融合
    Core.addWeighted(dstMat, 0.5d, srcMat, 1d, 0, dstMat); //把边缘叠加到原图

    Texture2D t2d = new Texture2D(dstMat.width(), dstMat.height());
    Sprite sp = Sprite.Create(t2d, new UnityEngine.Rect(0, 0, t2d.width, t2d.height), Vector2.zero);
    m_blurImage.sprite = sp;
    m_blurImage.preserveAspect = true;
    Utils.matToTexture2D(dstMat, t2d);
}

最终效果