예제 #1
0
def transect_yx(z, atr, start_yx, end_yx, interpolation='nearest'):
    """Extract 2D matrix (z) value along the line [x0,y0;x1,y1]
    Ref link: http://stackoverflow.com/questions/7878398/how-to-e
              xtract-an-arbitrary-line-of-values-from-a-numpy-array

    Parameters: z : (np.array)   2D data matrix
                atr : (dict) 2D data matrix attribute dictionary
                start_yx : (list) y,x coordinate of start point
                end_yx : (list) y,x coordinate of end   point
                interpolation : str, sampling/interpolation method, including:
                    'nearest'  - nearest neighbour, by default
                    'cubic'    - cubic interpolation
                    'bilinear' - bilinear interpolation

    Returns:    transect: N*2 matrix containing distance and value
                    N is the number of points.
                    1st col - distance in m
                    2nd col - value

    Example: transect = transect_yx(dem,demRsc,[10,15],[100,115])
    """

    # Extract the line
    [y0, x0] = start_yx
    [y1, x1] = end_yx
    length = int(np.hypot(x1-x0, y1-y0))
    x, y = np.linspace(x0, x1, length), np.linspace(y0, y1, length)
    transect = np.zeros([length, 2])

    # Y - Extract the value along the line
    if interpolation.lower() == 'nearest':
        zi = z[np.rint(y).astype(np.int), np.rint(x).astype(np.int)]
    elif interpolation.lower() == 'cubic':
        zi = scipy.ndimage.map_coordinates(z, np.vstack((y, x)))
    elif interpolation.lower() == 'bilinear':
        zi = scipy.ndimage.map_coordinates(z, np.vstack((y, x)), order=2)
    else:
        print('Unrecognized interpolation method: '+interpolation)
        print('Continue with nearest ...')
        zi = z[np.rint(y).astype(np.int), np.rint(x).astype(np.int)]  # nearest neighbour
    transect[:, 1] = zi

    # X - Distance along the line
    earth_radius = 6371.0e3    # in meter
    coord = ut.coordinate(atr)
    try:
        atr['X_FIRST']
        [lat0, lat1] = coord.yx2lalo([y0, y1], coord_type='y')
        lat_c = (lat0 + lat1) / 2.
        x_step = float(atr['X_STEP']) * np.pi/180.0 * earth_radius * np.cos(lat_c * np.pi/180)
        y_step = float(atr['Y_STEP']) * np.pi/180.0 * earth_radius
    except:
        x_step = ut.range_ground_resolution(atr)
        y_step = ut.azimuth_ground_resolution(atr)
    dis_x = (x - x0) * x_step
    dis_y = (y - y0) * y_step
    transect[:, 0] = np.hypot(dis_x, dis_y)

    return transect
예제 #2
0
def ifgram_inversion_patch(ifgram_file,
                           box=None,
                           ref_phase=None,
                           obs_ds_name='unwrapPhase',
                           weight_func='var',
                           water_mask_file=None,
                           min_norm_velocity=True,
                           mask_ds_name=None,
                           mask_threshold=0.4,
                           min_redundancy=1.0):
    """Invert one patch of an ifgram stack into timeseries.

    Parameters: box               - tuple of 4 int, indicating (x0, y0, x1, y1) of the area of interest
                                    or None for the whole image
                ifgram_file       - str, interferograms stack HDF5 file, e.g. ./inputs/ifgramStack.h5
                ref_phase         - 1D array in size of (num_ifgram), or None
                obs_ds_name       - str, dataset to feed the inversion.
                weight_func       - str, weight function, choose in ['no', 'fim', 'var', 'coh']
                water_mask_file   - str, water mask filename if available, to skip inversion on water
                min_norm_velocity - bool, minimize the residual phase or phase velocity
                mask_ds_name      - str, dataset name in ifgram_file used to mask unwrapPhase pixelwisely
                mask_threshold    - float, min coherence of pixels if mask_dataset_name='coherence'
                min_redundancy    - float, the min number of ifgrams for every acquisition.
    Returns:    ts                - 3D array in size of (num_date, num_row, num_col)
                temp_coh          - 2D array in size of (num_row, num_col)
                num_inv_ifg       - 2D array in size of (num_row, num_col)
                box               - tuple of 4 int
    Example:    ifgram_inversion_patch('ifgramStack.h5', box=(0,200,1316,400))
    """

    stack_obj = ifgramStack(ifgram_file)
    stack_obj.open(print_msg=False)

    # debug
    #y, x = 258, 454
    #box = (x, y, x+1, y+1)

    ## 1. input info

    # size
    if box:
        num_row = box[3] - box[1]
        num_col = box[2] - box[0]
    else:
        num_row = stack_obj.length
        num_col = stack_obj.width
    num_pixel = num_row * num_col

    # get tbase_diff
    date_list = stack_obj.get_date_list(dropIfgram=True)
    num_date = len(date_list)
    tbase = np.array(ptime.date_list2tbase(date_list)[0], np.float32) / 365.25
    tbase_diff = np.diff(tbase).reshape(-1, 1)

    # design matrix
    date12_list = stack_obj.get_date12_list(dropIfgram=True)
    A, B = stack_obj.get_design_matrix4timeseries(date12_list=date12_list)[0:2]

    # prep for decor std time-series
    #if os.path.isfile('reference_date.txt'):
    #    ref_date = str(np.loadtxt('reference_date.txt', dtype=bytes).astype(str))
    #else:
    #    ref_date = date_list[0]
    #Astd = stack_obj.get_design_matrix4timeseries(date12_list=date12_list, refDate=ref_date)[0]
    #ref_idx = date_list.index(ref_date)
    #time_idx = [i for i in range(num_date)]
    #time_idx.remove(ref_idx)

    # skip zero value in the network inversion for phase
    if 'phase' in obs_ds_name.lower():
        skip_zero_value = True
    else:
        skip_zero_value = False

    # 1.1 read / calcualte weight
    if weight_func in ['no', 'sbas']:
        weight = None
    else:
        weight = calc_weight(stack_obj,
                             box,
                             weight_func=weight_func,
                             dropIfgram=True,
                             chunk_size=100000)

    # 1.2 read / mask unwrapPhase / offset
    pha_data = read_unwrap_phase(stack_obj,
                                 box,
                                 ref_phase,
                                 obs_ds_name=obs_ds_name,
                                 dropIfgram=True)

    pha_data = mask_unwrap_phase(pha_data,
                                 stack_obj,
                                 box,
                                 dropIfgram=True,
                                 mask_ds_name=mask_ds_name,
                                 mask_threshold=mask_threshold)

    # 1.3 mask of pixels to invert
    mask = np.ones(num_pixel, np.bool_)

    # 1.3.1 - Water Mask
    if water_mask_file:
        print('skip pixels on water with mask from file: {}'.format(
            os.path.basename(water_mask_file)))
        atr_msk = readfile.read_attribute(water_mask_file)
        len_msk, wid_msk = int(atr_msk['LENGTH']), int(atr_msk['WIDTH'])
        if (len_msk, wid_msk) != (stack_obj.length, stack_obj.width):
            raise ValueError(
                'Input water mask file has different size from ifgramStack file.'
            )

        dsName = [
            i for i in readfile.get_dataset_list(water_mask_file)
            if i in ['waterMask', 'mask']
        ][0]
        waterMask = readfile.read(water_mask_file, datasetName=dsName,
                                  box=box)[0].flatten()
        mask *= np.array(waterMask, dtype=np.bool_)
        del waterMask

    # 1.3.2 - Mask for Zero Phase in ALL ifgrams
    if 'phase' in obs_ds_name.lower():
        print('skip pixels with zero/nan value in all interferograms')
        with warnings.catch_warnings():
            # ignore warning message for all-NaN slices
            warnings.simplefilter("ignore", category=RuntimeWarning)
            phase_stack = np.nanmean(pha_data, axis=0)
        mask *= np.multiply(~np.isnan(phase_stack), phase_stack != 0.)
        del phase_stack

    # 1.3.3 invert pixels on mask 1+2
    num_pixel2inv = int(np.sum(mask))
    idx_pixel2inv = np.where(mask)[0]
    print('number of pixels to invert: {} out of {} ({:.1f}%)'.format(
        num_pixel2inv, num_pixel, num_pixel2inv / num_pixel * 100))

    ## 2. inversion

    # 2.1 initiale the output matrices
    ts = np.zeros((num_date, num_pixel), np.float32)
    #ts_std = np.zeros((num_date, num_pixel), np.float32)
    temp_coh = np.zeros(num_pixel, np.float32)
    num_inv_ifg = np.zeros(num_pixel, np.int16)

    # return directly if there is nothing to invert
    if num_pixel2inv < 1:
        ts = ts.reshape(num_date, num_row, num_col)
        #ts_std = ts_std.reshape(num_date, num_row, num_col)
        temp_coh = temp_coh.reshape(num_row, num_col)
        num_inv_ifg = num_inv_ifg.reshape(num_row, num_col)
        return ts, temp_coh, num_inv_ifg

    # 2.2 un-weighted inversion (classic SBAS)
    if weight_func in ['no', 'sbas']:

        # a. mask for Non-Zero Phase in ALL ifgrams (share one B in sbas inversion)
        if 'phase' in obs_ds_name.lower():
            mask_all_net = np.all(pha_data, axis=0)
            mask_all_net *= mask
        else:
            mask_all_net = np.array(mask)
        mask_part_net = mask ^ mask_all_net
        del mask

        # b. invert once for all pixels with obs in all ifgrams
        if np.sum(mask_all_net) > 0:
            print(('inverting pixels with valid phase in all  ifgrams'
                   ' ({:.0f} pixels) ...').format(np.sum(mask_all_net)))
            tsi, tcohi, num_ifgi = estimate_timeseries(
                A,
                B,
                tbase_diff,
                ifgram=pha_data[:, mask_all_net],
                weight_sqrt=None,
                min_norm_velocity=min_norm_velocity,
                min_redundancy=min_redundancy,
                skip_zero_value=skip_zero_value)
            ts[:, mask_all_net] = tsi
            temp_coh[mask_all_net] = tcohi
            num_inv_ifg[mask_all_net] = num_ifgi

        # c. pixel-by-pixel for pixels with obs not in all ifgrams
        if np.sum(mask_part_net) > 0:
            print(('inverting pixels with valid phase in some ifgrams'
                   ' ({:.0f} pixels) ...').format(np.sum(mask_part_net)))
            num_pixel2inv = int(np.sum(mask_part_net))
            idx_pixel2inv = np.where(mask_part_net)[0]
            prog_bar = ptime.progressBar(maxValue=num_pixel2inv)
            for i in range(num_pixel2inv):
                idx = idx_pixel2inv[i]
                tsi, tcohi, num_ifgi = estimate_timeseries(
                    A,
                    B,
                    tbase_diff,
                    ifgram=pha_data[:, idx],
                    weight_sqrt=None,
                    min_norm_velocity=min_norm_velocity,
                    min_redundancy=min_redundancy,
                    skip_zero_value=skip_zero_value)
                ts[:, idx] = tsi.flatten()
                temp_coh[idx] = tcohi
                num_inv_ifg[idx] = num_ifgi
                prog_bar.update(i + 1,
                                every=2000,
                                suffix='{}/{} pixels'.format(
                                    i + 1, num_pixel2inv))
            prog_bar.close()

    # 2.3 weighted inversion - pixel-by-pixel
    else:
        print('inverting network of interferograms into time-series ...')
        prog_bar = ptime.progressBar(maxValue=num_pixel2inv)
        for i in range(num_pixel2inv):
            idx = idx_pixel2inv[i]
            tsi, tcohi, num_ifgi = estimate_timeseries(
                A,
                B,
                tbase_diff,
                ifgram=pha_data[:, idx],
                weight_sqrt=weight[:, idx],
                min_norm_velocity=min_norm_velocity,
                min_redundancy=min_redundancy,
                skip_zero_value=skip_zero_value)
            ts[:, idx] = tsi.flatten()
            temp_coh[idx] = tcohi
            num_inv_ifg[idx] = num_ifgi

            prog_bar.update(i + 1,
                            every=2000,
                            suffix='{}/{} pixels'.format(i + 1, num_pixel2inv))
        prog_bar.close()
        del weight
    del pha_data

    ## 3. prepare output

    # 3.1 reshape
    ts = ts.reshape(num_date, num_row, num_col)
    #ts_std = ts_std.reshape(num_date, num_row, num_col)
    temp_coh = temp_coh.reshape(num_row, num_col)
    num_inv_ifg = num_inv_ifg.reshape(num_row, num_col)

    # 3.2 convert displacement unit to meter
    if obs_ds_name.startswith('unwrapPhase'):
        phase2range = -1 * float(
            stack_obj.metadata['WAVELENGTH']) / (4. * np.pi)
        ts *= phase2range
        print('converting LOS phase unit from radian to meter')

    elif obs_ds_name == 'azimuthOffset':
        az_pixel_size = ut.azimuth_ground_resolution(stack_obj.metadata)
        ts *= az_pixel_size
        print('converting azimuth offset unit from pixel ({:.2f} m) to meter'.
              format(az_pixel_size))

    elif obs_ds_name == 'rangeOffset':
        rg_pixel_size = float(stack_obj.metadata['RANGE_PIXEL_SIZE'])
        ts *= rg_pixel_size
        print('converting range offset unit from pixel ({:.2f} m) to meter'.
              format(rg_pixel_size))

    return ts, temp_coh, num_inv_ifg, box