Zarr loading and converting

qim3d/io/__init__.py

@@ -2,4 +2,5 @@ from .loading import DataLoader, load, ImgExamples
 from .downloader import Downloader
 from .saving import DataSaver, save 
 from .sync import Sync
+from .convert import convert
 from . import logger
\ No newline at end of file

qim3d/io/convert.py

+import difflib
+import os
+from itertools import product
+
+import numpy as np
+import tifffile as tiff
+import zarr
+from tqdm import tqdm
+
+from qim3d.utils.internal_tools import stringify_path
+
+
+class Convert:
+
+    def __init__(self,**kwargs):
+        """ Utility class to convert files to other formats without loading the entire file into memory
+
+        Args:
+            chunk_shape (tuple, optional): chunk size for the zarr file. Defaults to (64, 64, 64).
+        """
+        self.chunk_shape = kwargs.get("chunk_shape", (64, 64, 64))
+
+    def convert(self, input_path, output_path):
+        # Stringify path in case it is not already a string
+        input_path = stringify_path(input_path)
+        input_ext = os.path.splitext(input_path)[1]
+        output_ext = os.path.splitext(output_path)[1]
+        output_path = stringify_path(output_path)
+
+        if os.path.isfile(input_path):  
+            match input_ext, output_ext:
+                case (".tif", ".zarr")  | (".tiff", ".zarr"):
+                    return self.convert_tif_to_zarr(input_path, output_path)
+                case _:
+                    raise ValueError("Unsupported file format")
+        # Load a directory
+        elif os.path.isdir(input_path):
+            match input_ext, output_ext:
+                case (".zarr", ".tif") | (".zarr", ".tiff"):
+                    return self.convert_zarr_to_tif(input_path, output_path)
+                case _:
+                    raise ValueError("Unsupported file format")
+        # Fail
+        else:
+            # Find the closest matching path to warn the user
+            parent_dir = os.path.dirname(input_path) or "."
+            parent_files = os.listdir(parent_dir) if os.path.isdir(parent_dir) else ""
+            valid_paths = [os.path.join(parent_dir, file) for file in parent_files]
+            similar_paths = difflib.get_close_matches(input_path, valid_paths)
+            if similar_paths:
+                suggestion = similar_paths[0]  # Get the closest match
+                message = f"Invalid path. Did you mean '{suggestion}'?"
+                raise ValueError(repr(message))
+            else:
+                raise ValueError("Invalid path")
+
+    def convert_tif_to_zarr(self, tif_path, zarr_path, chunks=(64, 64, 64)):
+        """ Convert a tiff file to a zarr file
+
+        Args:
+            tif_path (str): path to the tiff file
+            zarr_path (str): path to the zarr file
+            chunks (tuple, optional): chunk size for the zarr file. Defaults to (64, 64, 64).
+
+        Returns:
+            zarr.core.Array: zarr array containing the data from the tiff file
+        """
+        vol = tiff.memmap(tif_path)
+        z = zarr.open(zarr_path, mode='w', shape=vol.shape, chunks=chunks, dtype=vol.dtype)
+        chunk_shape = tuple((s + c - 1) // c for s, c in zip(z.shape, z.chunks))
+        # ! Fastest way is z[:] = vol[:], but does not have a progress bar
+        for chunk_indices in tqdm(product(*[range(n) for n in chunk_shape]), total=np.prod(chunk_shape)):
+            slices = tuple(slice(c * i, min(c * (i + 1), s))
+                        for s, c, i in zip(z.shape, z.chunks, chunk_indices))
+            temp_data = vol[slices]
+            # The assignment takes 99% of the cpu-time
+            z.blocks[chunk_indices] = temp_data
+
+        return z
+
+    def convert_zarr_to_tif(self, zarr_path, tif_path):
+        """ Convert a zarr file to a tiff file
+
+        Args:
+            zarr_path (str): path to the zarr file
+            tif_path (str): path to the tiff file
+
+        returns:
+            None
+        """
+        z = zarr.open(zarr_path)
+        tiff.imwrite(tif_path, z)
+
+
+def convert(input_path: str, output_path: str, chunk_shape: tuple = (64, 64, 64)):
+    """ Convert a file to another format without loading the entire file into memory
+
+    Args:
+        input_path (str): path to the input file
+        output_path (str): path to the output file
+        chunk_shape (tuple, optional): chunk size for the zarr file. Defaults to (64, 64, 64).
+    """
+
+    converter = Convert(chunk_shape=chunk_shape)
+    converter.convert(input_path, output_path)

qim3d/io/loading.py

@@ -606,6 +606,27 @@ class DataLoader:
         else:
             return vol
         
+
+    def load_zarr(self, path: str):
+        """ Loads a Zarr array from disk.
+
+        Args:
+            path (str): The path to the Zarr array on disk.
+
+        Returns:
+            dask.array | numpy.ndarray: The dask array loaded from disk.
+                if 'self.virtual_stack' is True, returns a dask array object, else returns a numpy.ndarray object.
+        """
+
+        # Opens the Zarr array
+        vol = da.from_zarr(path)
+
+        # If virtual stack is disabled, return the computed array (np.ndarray)
+        if not self.virtual_stack:
+            vol = vol.compute()
+
+        return vol
+
     def check_file_size(self, filename: str):
         """
         Checks if there is enough memory where the file can be loaded.
@@ -693,6 +714,8 @@ class DataLoader:
 
             elif any([f.endswith(self.PIL_extensions) for f in os.listdir(path)]):
                 return self.load_PIL_stack(path)
+            elif path.endswith(".zarr"):
+                return self.load_zarr(path)
             else:
                 return self.load_dicom_dir(path)
 

qim3d/io/saving.py

@@ -24,9 +24,17 @@ Example:
 
 import datetime
 import os
+
+import dask.array as da
+import h5py
+import nibabel as nib
 import numpy as np
 import PIL
 import tifffile
+import zarr
+from pydicom.dataset import FileDataset, FileMetaDataset
+from pydicom.uid import UID
+
 from qim3d.io.logger import log
 from qim3d.utils.internal_tools import sizeof, stringify_path
 
@@ -249,6 +257,22 @@ class DataSaver:
 
         ds.save_as(path)
 
+    def save_to_zarr(self, path, data):
+        """ Saves a Dask array to a Zarr array on disk.
+
+        Args:
+            path (str): The path to the Zarr array on disk.
+            data (dask.array): The Dask array to be saved to disk.
+
+        Returns:
+            zarr.core.Array: The Zarr array saved on disk.
+        """
+        assert isinstance(data, da.Array), 'data must be a dask array'
+
+        # forces compute when saving to zarr
+        da.to_zarr(data, path, compute=True, overwrite=self.replace, compressor=zarr.Blosc(cname='zstd', clevel=3, shuffle=2))
+        
+    
     def save_PIL(self, path, data):
         """Save data to a PIL file to the given path.
 
@@ -344,6 +368,8 @@ class DataSaver:
                         return self.save_vol(path, data)
                     elif path.endswith((".dcm", ".DCM")):
                         return self.save_dicom(path, data)
+                    elif path.endswith((".zarr")):
+                        return self.save_to_zarr(path, data)
                     elif path.endswith((".jpeg",".jpg", ".png")):
                         return self.save_PIL(path, data)
                     else: