C++ OutputArray::isMat方法代码示例

//static
void QualityBRISQUE::computeFeatures(InputArray img, OutputArray features)
{
    CV_Assert(features.needed());
    CV_Assert(img.isMat());
    CV_Assert(!img.getMat().empty());

    auto mat = mat_convert(img.getMat());

    const auto vals = ComputeBrisqueFeature(mat);
    cv::Mat valmat( cv::Size( (int)vals.size(), 1 ), CV_32FC1, (void*)vals.data()); // create row vector, type depends on brisque_calc_element_type

    if (features.isUMat())
        valmat.copyTo(features.getUMatRef());
    else if (features.isMat())
        // how to move data instead?
        // if calling this:
        //      features.getMatRef() = valmat;
        //  then shared data is erased when valmat is released, corrupting the data in the outputarray for the caller
        valmat.copyTo(features.getMatRef());
    else
        CV_Error(cv::Error::StsNotImplemented, "Unsupported output type");
}

void HDF5Impl::dsread( OutputArray Array, const String& dslabel,
             const int* dims_offset, const int* dims_counts ) const
{
    // only Mat support
    CV_Assert( Array.isMat() );

    hid_t h5type;

    // open the HDF5 dataset
    hid_t dsdata = H5Dopen( m_h5_file_id, dslabel.c_str(), H5P_DEFAULT );

    // get data type
    hid_t dstype = H5Dget_type( dsdata );

    int channs = 1;
    if ( H5Tget_class( dstype ) == H5T_ARRAY )
    {
      // fetch channs
      hsize_t ardims[1];
      H5Tget_array_dims( dstype, ardims );
      channs = (int) ardims[0];
      // fetch depth
      hid_t tsuper = H5Tget_super( dstype );
      h5type = H5Tget_native_type( tsuper, H5T_DIR_ASCEND );
      H5Tclose( tsuper );
    } else
      h5type = H5Tget_native_type( dstype, H5T_DIR_ASCEND );

    int dType = GetCVtype( h5type );

    // get file space
    hid_t fspace = H5Dget_space( dsdata );

    // fetch rank
    int n_dims = H5Sget_simple_extent_ndims( fspace );

    // fetch dims
    hsize_t *dsdims = new hsize_t[n_dims];
    H5Sget_simple_extent_dims( fspace, dsdims, NULL );

    // set amount by custom offset
    if ( dims_offset != NULL )
    {
      for ( int d = 0; d < n_dims; d++ )
        dsdims[d] -= dims_offset[d];
    }

    // set custom amount of data
    if ( dims_counts != NULL )
    {
      for ( int d = 0; d < n_dims; d++ )
        dsdims[d] = dims_counts[d];
    }

    // get memory write window
    int *mxdims = new int[n_dims];
    hsize_t *foffset = new hsize_t[n_dims];
    for ( int d = 0; d < n_dims; d++ )
    {
      foffset[d] = 0;
      mxdims[d] = (int) dsdims[d];
    }

    // allocate persistent Mat
    Array.create( n_dims, mxdims, CV_MAKETYPE(dType, channs) );

    // get blank data space
    hid_t dspace = H5Screate_simple( n_dims, dsdims, NULL );

    // get matrix write window
    H5Sselect_hyperslab( dspace, H5S_SELECT_SET,
                         foffset, NULL, dsdims, NULL );

    // set custom offsets
    if ( dims_offset != NULL )
    {
      for ( int d = 0; d < n_dims; d++ )
        foffset[d] = dims_offset[d];
    }

    // get a file read window
    H5Sselect_hyperslab( fspace, H5S_SELECT_SET,
                         foffset, NULL, dsdims, NULL );

    // read from DS
    Mat matrix = Array.getMat();
    H5Dread( dsdata, dstype, dspace, fspace, H5P_DEFAULT, matrix.data );

    delete [] dsdims;
    delete [] mxdims;
    delete [] foffset;

    H5Tclose (h5type );
    H5Tclose( dstype );
    H5Sclose( dspace );
    H5Sclose( fspace );
    H5Dclose( dsdata );
}