#!/usr/bin/env python # coding: utf-8 # by Andreas Bauer and David Boehringer, 19.06.2020 # This script contains two examples for 3D-PIV: The shift of a bar of binary pixels in one direction, the expansion # and a real data set where we recorded two stacks of collagen fibres at the same field of view with confocal microscopy # in reflection mode. One stack contains a NK cell that deforms the matrix and the other doe not. # Please download the data at https://github.com/fabrylab/3D_piv_example_data.git (180 MB, unpacked) and provide the # folder in the code below. # We tested this on ubuntu 16 and 18, with Anaconda Python installation. The whole script # takes about 5 minutes on my 4 core-intel i5 @2.5 GHz Laptop. You should have !!! 8 Gb ob Memory !!!! or take care not # to open all matplotlib plots as interactive windows at once. # For questions contact andreas.b.bauer@fau.de # # In[1]: from openpiv.pyprocess3D import * from openpiv.PIV_3D_plotting import * from openpiv.validation import sig2noise_val from openpiv.filters import replace_outliers from openpiv.lib import replace_nans import glob as glob import os from natsort import natsorted import matplotlib.animation as animation # Make save_plots = True if you want to compare the # visual results # In[2]: save_plots = False out_put_folder = "output_3D_test" if save_plots: if not os.path.exists(out_put_folder): try: os.mkdir(out_put_folder) except: print("could not generate output folder") save_plots = False # ############ a group of bars shifted by 1 pixel to the each dimesion the second frame ############# # takes ~4 seconds # In[3]: # constructing frame 1 and frame 2 size = (32, 32, 32) shape1 = np.zeros(size) shape2 = np.zeros(size) # In[4]: shape1[16, 16, 25:27] = 1 shape1[16, 16, 7:9] = 1 shape1[16, 25:27, 16] = 1 shape1[16, 7:9, 16] = 1 shape1[25:27, 16, 16] = 1 shape1[7:9, 16, 16] = 1 # In[5]: shape2[16, 16, 24:26] = 1 shape2[16, 16, 8:10] = 1 shape2[16, 24:26, 16] = 1 shape2[16, 8:10, 16] = 1 shape2[24:26, 16, 16] = 1 shape2[8:10, 16, 16] = 1 # In[6]: window_size = (4, 4, 4) overlap = (3, 3, 3) search_area = (5, 5, 5) # In[7]: u, v, w, sig2noise = extended_search_area_piv3D(shape1, shape2, window_size=window_size, overlap=overlap, search_area_size=search_area, subpixel_method='gaussian', sig2noise_method='peak2peak', width=2) # In[8]: get_ipython().run_line_magic('pdb', '') # displaying the shapes with 3D scatter plot fig1 = scatter_3D(shape1, control="size") fig2 = scatter_3D(shape2, control="size") # 3d plot of the signal-to-noise rations fig3 = scatter_3D(sig2noise, control="size") # 3d quiver plot of the displacement field fig4 = quiver_3D(-u, v, w, cmap="coolwarm", quiv_args={"arrow_length_ratio":0.6}) # In[9]: # saving the plots if save_plots: fig1.savefig(os.path.join(out_put_folder, "displaced_bar_frame1.png")) fig2.savefig(os.path.join(out_put_folder, "displaced_bar_frame2.png")) fig3.savefig(os.path.join(out_put_folder, "displaced_bar_sig2noise.png")) fig4.savefig(os.path.join(out_put_folder, "displaced_bar_deformation_field.png")) # ################### test to check the replace_nans_function ###################### # takes ~4 seconds # In[10]: # ball shape with a gap of nans in the middle center = (5, 5, 5) size = (10, 10, 10) distance = np.linalg.norm(np.subtract(np.indices(size).T, np.asarray(center)), axis=len(center)) arr = np.ones(size) * (distance <= 5) hide = arr == 0 arr[5:7] = np.nan # In[11]: # displaying in 3d plots. Values outside of the original ball are hidden by setting to nan arr_show = arr.copy() arr_show[hide] = np.nan fig9 = scatter_3D(arr_show, size=50, sca_args={"alpha": 0.6}) # replacing outliers arr = replace_nans(arr, max_iter=2, tol=2, kernel_size=2, method='disk') # In[12]: # displaying in 3d plots. Values outside of the original ball are hidden by setting to nan arr_show = arr.copy() arr_show[hide] = np.nan fig10 = scatter_3D(arr_show, size=50, sca_args={"alpha": 0.6}) # In[13]: # saving the plots if save_plots: fig9.savefig(os.path.join(out_put_folder, "replace_nan_gap.png")) fig10.savefig(os.path.join(out_put_folder, "replace_nan_filled.png")) # #################### real data example ############################ # we recorded stacks of collagen fibres with confocal microscopy in reflection mode # "alive" stack contains a force generating NK-cell, marked by the red circle in the animation # "relaxed" stack is the same field of view with out the cell # download the data at https://github.com/fabrylab/3D_piv_example_data.git # this calculation takes ~ 3-4 minutes on my 4-core Intel i5@2.5 GHz Laptop # In[14]: # please enter the path to the dataset provided at folder = r"test_3d" # In[15]: if not os.path.exists(folder): import git repo = git.Repo.clone_from("https://github.com/fabrylab/3D_piv_example_data.git", './test_3d', branch='master') # In[16]: if not os.path.exists(folder): raise FileNotFoundError("path to 3d piv data '%s' does not exists\n" ". Please download the data from https://github.com/fabrylab/3D_piv_example_data.git" % folder) # stack properties # factors for voxel size du = 0.2407 dv = 0.2407 dw = 1.0071 # total image dimension for x y z image_dim = (123.02, 123.02, 122.86) # In[17]: # keep these values for our nk cells stacks win_um = 12 # window size in µm fac_overlap = 0.3 # overlap in percent of the window size signoise_filter = 1.3 # In[18]: # window size for stacks in pixel window_size = (int(win_um / du), int(win_um / dv), int(win_um / dw)) overlap = (int(fac_overlap * win_um / du), int(fac_overlap * win_um / dv), int(fac_overlap * win_um / dw)) search_area = (int(win_um / du), int(win_um / dv), int(win_um / dw)) # In[19]: # load tense stacks images = natsorted(glob.glob(os.path.join(folder, "Series001_t22_z*_ch00.tif"))) im_shape = plt.imread(images[0]).shape alive = np.zeros((im_shape[0], im_shape[1], len(images))) for i, im in enumerate(images): alive[:, :, i] = plt.imread(im) # In[20]: # load relaxed stack images = natsorted(glob.glob(os.path.join(folder, "Series003_t05_z*_ch00.tif"))) im_shape = plt.imread(images[0]).shape relax = np.zeros((im_shape[0], im_shape[1], len(images))) for i, im in enumerate(images): relax[:, :, i] = plt.imread(im) # In[21]: # 3D PIV u, v, w, sig2noise = extended_search_area_piv3D(relax, alive, window_size=window_size, overlap=overlap, search_area_size=search_area, dt=(1 / du, 1 / dv, 1 / dw), subpixel_method='gaussian', sig2noise_method='peak2peak', width=2) # In[22]: # correcting stage drift between the field of views u -= np.nanmean(u) v -= np.nanmean(v) w -= np.nanmean(w) # In[23]: # filtering uf, vf, wf, mask = sig2noise_val(u, v, w=w, s2n=sig2noise, threshold=signoise_filter) uf, vf, wf = replace_outliers(uf, vf, wf, max_iter=1, tol=100, kernel_size=2, method='disk') # In[24]: # plotting # representation of the image stacks by maximums projections. The red circle marks the position of the cell def update_plot(i, ims, ax): a1 = ax.imshow(ims[i]) a2 = ax.add_patch(plt.Circle((330, 140), 100, color="red", fill=False)) return [a1, a2] # In[25]: ims = [np.max(relax[:, :, 60:], axis=2), np.max(alive[:, :, 60:], axis=2)] fig = plt.figure() ax = plt.gca() ani = animation.FuncAnimation(fig, update_plot, 2, interval=200, blit=True, repeat_delay=0, fargs=(ims, ax)) # In[26]: # unfiltered 3d deformation field fig11 = quiver_3D(-u, v, w, quiv_args={"length": 2, "alpha": 0.8, "linewidth": 1}, filter_def=0.1) # In[27]: # filtered 3d deformation field fig12 = quiver_3D(-uf, vf, wf, quiv_args={"length": 2, "alpha": 0.8, "linewidth": 1}, filter_def=0.1) # In[28]: # saving the plots if save_plots: fig11.savefig(os.path.join(out_put_folder, "real_data_unfiltered.png")) fig12.savefig(os.path.join(out_put_folder, "real_data_filtered.png")) # This needs a working ImageMagick installation, and probably works only on linux try: import imageio plt.ioff() f1 = plt.figure() plt.imshow(ims[0]) plt.gca().add_artist(plt.Circle((330, 140), 100, color="red", fill=False)) f1.savefig(os.path.join(out_put_folder,"tem1.png")) f2 = plt.figure() plt.imshow(ims[1]) plt.gca().add_artist(plt.Circle((330, 140), 100, color="red", fill=False)) f2.savefig(os.path.join(out_put_folder,"tem2.png")) i1 = plt.imread(os.path.join(out_put_folder,"tem1.png")) i2 = plt.imread(os.path.join(out_put_folder, "tem2.png")) imageio.mimsave(os.path.join(out_put_folder, "reaL_data_max_proj.gif"),[i1,i2], fps=1) os.remove(os.path.join(out_put_folder,"tem1.png")) os.remove(os.path.join(out_put_folder,"tem2.png")) plt.ion() except Exception as e: print ("failed to write gif of collagen embedded cell:") print(e)