JNI之OpenCV卷积操作

    // [
    //  0,-1,0,
    //  -1,5,-1,
    //  0,-1,0
    // ]

    // 卷积操作
    Mat source;
    bitmap2mat(env, source, bitmap);
    // 生成一个全零矩阵
    Mat dest = Mat::zeros(source.size(), source.type());
    // 获取列数
    int cols = (source.cols - 1) * source.channels();
    int rows = source.rows;
    int offset_x = source.channels();
    for (int row = 1; row < rows - 1; row++) {
        // 上一行
        uchar *pre = source.ptr<uchar>(row - 1);
        // 当前行
        uchar *current = source.ptr<uchar>(row);
        // 下一行
        uchar *next = source.ptr<uchar>(row + 1);
        // 输出
        uchar *output = dest.ptr<uchar>(row);

        for (int col = offset_x; col < cols; col++) {
            output[col] = saturate_cast<uchar>(
                    5 * current[col] - current[col - offset_x] - current[col + offset_x] - pre[col] - next[col]);
        }
    }

//    Mat dest;
//    Mat kennel = (Mat_<char>(3,3) << 0,-1,0,-1,5,-1,0,-1,0);
//    filter2D(source,dest,source.depth(),kennel);

    mat2bitmap(env,dest,bitmap);