aicspylibczi 2.2.0

A python module and a python extension for Zeiss (CZI/ZISRAW) microscopy files.

aicspylibczi

Python module to expose libCZI functionality for reading (subset of) Zeiss CZI files and meta-data.

Usage

The first example show how to work with a standard CZI file (Single or Multe-Scene). The second example shows how to work with a Mosaic CZI file.

Example 1: Read in a czi and select a portion of the image to display

import numpy as np
from aicspylibczi import CziFile
from pathlib import Path
import matplotlib.pyplot as plt

pth = Path('20190610_S02-02.czi')
czi = CziFile(pth)

# Get the shape of the data, the coordinate pairs are (start index, size)
dimensions = czi.dims_shape()  # {'Z': (0, 70), 'C': (0, 2), 'T': (0, 146), 'S': (0, 12), 'B': (0, 1)}

czi.dims  #  BSTCZYX

czi.size  #  (1, 12, 146, 2, 70, 1300, 1900) 

# Load the image slice I want from the file
img, shp = czi.read_image(S=13, Z=16)

# shp = [('B', 1), ('S', 1), ('C', 4), ('Z', 1), ('Y', 1300), ('X', 1900)]  # List[(Dimension, size), ...] 
# img.shape = (1, 1, 4, 1, 1300, 1900)   # numpy.ndarray

# define helper functions
def norm_by(x, min, max):
    norms = np.percentile(x, [min, max])
    i2 = np.clip((x - norms[0])/(norms[1]-norms[0]), 0, 1)
    i2
    return i2

def recolor(im): # transform from rgb to cyan-magenta-yellow
    im_shape = np.array(im.shape)
    color_transform = np.array([[1, 1, 0], [0, 1, 1], [1, 0, 1]]).T
    im_reshape = im.reshape([np.prod(im_shape[0:2]), im_shape[2]]).T
    im_recolored = np.matmul(color_transform.T, im_reshape).T
    im_shape[2] = 3
    im = im_recolored.reshape(im_shape)
    return im

#normalize, combine into RGB and transform to CMY
c1 = (norm_by(img[0, 0, 0, 0, 0:750, 250:1000], 50, 99.8)*255).astype(np.uint8)
c2 = (norm_by(img[0, 0, 1, 0, 0:750, 250:1000], 50, 99.8)*255).astype(np.uint8)
c3 = (norm_by(img[0, 0, 2, 0, 0:750, 250:1000], 0, 100)*255).astype(np.uint8)
rgb = np.stack((c1, c2, c3), axis=2)
cmy = np.clip(recolor(rgb), 0, 255)

# plot using matplotlib¶
plt.figure(figsize=(10,10))
plt.imshow(cmy)
plt.axis('off')

Example 2: Read in a mosaic file

import numpy as np
import aicspylibczi
import pathlib
from PIL import Image


mosaic_file = pathlib.Path('20190618_CL001_HB01_Rescan_002.czi').expanduser()
czi = aicspylibczi.CziFile(mosaic_file)

# Get the shape of the data
dimensions = czi.dims   #  'STCZMYX'

czi.size  # (1, 1, 1, 1, 2, 624, 924)

czi.dims_shape()  # {'C': (0, 0), 'M': (0, 1), 'S': (0, 0), 'T': (0, 0), 'X': (0, 923), 'Y': (0, 623), 'Z': (0, 0)}

czi.is_mosaic()  # True 
 # Mosaic files ignore the S dimension and use an internal mIndex to reconstruct, the scale factor allows one to generate a manageable image
mosaic_data = czi.read_mosaic(C=0, scale_factor=1) 

mosaic_data.shape  #  (1, 1, 624, 1756)
 # the C channel has been specified S & M are used internally for position so this is (T, Z, Y, X)

normed_mosaic_data = norm_by(mosaic_data[0, 0, :, :], 5, 98)*255
img = Image.fromarray(normed_mosaic_data.astype(np.uint8))

Installation

The preferred installation method is with pip install. This will install the aicspylibczi python module and extension binaries (hosted on PyPI):

pip install aicspylibczi

Documentation

Documentation is available at github.io and readthedocs.

Build

Use these steps to build and install aicspylibczi locally:

• Clone the repository including submodules (--recurse-submodules).
• Requirements:
  • libCZI requires a c++11 compatible compiler. Built & Tested with clang.
  • Development requirements are those required for libCZI: libpng, zlib
  • Install the package:

    pip install .
    pip install -e .[dev] # for development (-e means editable so changes take effect when made)
    pip install .[all] # for everything including jupyter notebook to work with the Example_Usage above
    

  • libCZI is automatically built as a submodule and linked statically into aicspylibczi.
• Note: If you get the message directly below on windows you need to set PYTHONHOME to be the folder the python.exe you are compiling against lives in.

EXEC : Fatal Python error : initfsencoding: unable to load the file system codec ... 
ModuleNotFoundError: No module named 'encodings'

License

The GPLv3 license is a consequence of libCZI which imposes GPLv3. If you wish to use libCZI or this derivative in a commercial product you'll need to talk to Zeiss.

History

aicspylibczi was originally a fork of pylibczi that was developed by Paul Watkins and focused on mSEM data. In attempting to extend the work to we transitioned to pybind11, implemented c++ and python tests, added continuous integration via github actions, and added the functionality to read individual subblocks and stacks of subblocks as a numpy.ndarray. Metadata reading, including specific subblock metadata reading has also been added.

We intend for this work to be merged back into the original project once we have the new work integrated with the original work.