Ejemplo n.º 1
0
    def __init__(self,
                 array: np.ndarray,
                 voxel_offset: Cartesian = None,
                 voxel_size: Cartesian = None):
        assert array.ndim >= 3 and array.ndim <= 4
        assert isinstance(array, np.ndarray) or isinstance(array, Chunk)

        self.array = array
        if voxel_offset is None:
            if isinstance(array, Chunk):
                self.array = array.array
                voxel_offset = array.voxel_offset
            else:
                voxel_offset = Cartesian(0, 0, 0)

        if voxel_offset is not None:
            if len(voxel_offset) == 4:
                assert voxel_offset[0] == 0
                voxel_offset = voxel_offset[1:]
            assert len(voxel_offset) == 3

        if not isinstance(voxel_offset, Cartesian):
            voxel_offset = Cartesian.from_collection(voxel_offset)
        self.voxel_offset = voxel_offset

        if voxel_size is not None and not isinstance(voxel_size, Cartesian):
            voxel_size = Cartesian.from_collection(voxel_size)
        self.voxel_size = voxel_size
        if voxel_size is not None:
            assert len(voxel_size) == 3
            assert np.alltrue([vs > 0 for vs in voxel_size])
Ejemplo n.º 2
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 def properties(self) -> dict:
     props = dict()
     if self.voxel_offset is not None or self.voxel_offset != Cartesian(
             0, 0, 0):
         props['voxel_offset'] = self.voxel_offset
     if self.voxel_size is not None or self.voxel_size != Cartesian(
             1, 1, 1):
         props['voxel_size'] = self.voxel_size
     return props
Ejemplo n.º 3
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    def __call__(self, output_bbox: BoundingBox):
        # if we do not clone this bounding box,
        # the bounding box in task will be modified!
        assert isinstance(output_bbox, BoundingBox)
        output_bbox = output_bbox.clone()
        output_bbox.adjust(self.expand_margin_size)
        chunk_slices = output_bbox.to_slices()

        if self.dry_run:
            # input_bbox = BoundingBox.from_slices(chunk_slices)
            # we can not use pattern=zero since it might got skipped by
            # the operator of skip-all-zero
            return Chunk.from_bbox(
                output_bbox,
                pattern='random',
                dtype=self.vol.dtype,
                voxel_size=Cartesian.from_collection(
                    self.vol.resolution[::-1]),
            )

        logging.info('cutout {} from {}'.format(chunk_slices[::-1],
                                                self.volume_path))

        # always reverse the indexes since cloudvolume use x,y,z indexing
        chunk = self.vol[chunk_slices[::-1]]
        chunk = np.asarray(chunk)
        # the cutout is fortran ordered, so need to transpose and make it C order
        chunk = chunk.transpose()

        # we can delay this transpose later
        # actually we do not need to make it contiguous
        # chunk = np.ascontiguousarray(chunk)

        # if the channel number is 1, squeeze it as 3d array
        # this should not be neccessary
        # TODO: remove this step and use 4D array all over this package.
        # always use 4D array will simplify some operations
        # voxel_offset = Cartesian(s.start for s in chunk_slices)
        if chunk.shape[0] == 1:
            chunk = np.squeeze(chunk, axis=0)

        chunk = Chunk(chunk,
                      voxel_offset=output_bbox.start,
                      voxel_size=Cartesian.from_collection(
                          self.vol.resolution[::-1]))

        if self.blackout_sections:
            chunk = self._blackout_sections(chunk)

        if self.validate_mip:
            self._validate_chunk(chunk)

        return chunk
Ejemplo n.º 4
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    def __init__(self,
                 volume_path: str,
                 mip: int = 0,
                 expand_margin_size: Cartesian = Cartesian(0, 0, 0),
                 expand_direction: int = None,
                 fill_missing: bool = False,
                 validate_mip: int = None,
                 blackout_sections: bool = None,
                 dry_run: bool = False,
                 name: str = 'cutout'):
        super().__init__(name=name)
        self.volume_path = volume_path
        self.mip = mip
        self.fill_missing = fill_missing
        self.validate_mip = validate_mip
        self.blackout_sections = blackout_sections
        self.dry_run = dry_run

        if isinstance(expand_margin_size, tuple):
            expand_margin_size = Cartesian.from_collection(expand_margin_size)

        if expand_direction == 1:
            expand_margin_size = (0, 0, 0, *expand_margin_size)
        elif expand_direction == -1:
            expand_margin_size = (*expand_margin_size, 0, 0, 0)
        else:
            assert expand_direction is None
        self.expand_margin_size = expand_margin_size

        if blackout_sections:
            stor = CloudFiles(volume_path)
            self.blackout_section_ids = stor.get_json(
                'blackout_section_ids.json')['section_ids']

        verbose = (logging.getLogger().getEffectiveLevel() <= 30)
        self.vol = CloudVolume(self.volume_path,
                               bounded=False,
                               fill_missing=self.fill_missing,
                               progress=verbose,
                               mip=self.mip,
                               cache=False,
                               green_threads=True)
Ejemplo n.º 5
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    def maskout(self, chunk: Chunk):
        """ Make part of the chunk to be black.
        """
        assert chunk.voxel_size is not None
        assert self.voxel_size is not None
        assert self.voxel_size >= chunk.voxel_size

        # the voxel size should be divisible
        assert Cartesian(0, 0, 0) == self.voxel_size % chunk.voxel_size

        factor = self.voxel_size // chunk.voxel_size
        for offset in np.ndindex(factor):
            chunk.array[..., np.s_[offset[0]::factor[0]],
                        np.s_[offset[1]::factor[1]],
                        np.s_[offset[2]::factor[2]]] *= self.array
Ejemplo n.º 6
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    def to_h5(self,
              file_name: str,
              with_offset: bool = True,
              chunk_size: Cartesian = Cartesian(64, 64, 64),
              with_unique: bool = True,
              compression="gzip",
              voxel_size: tuple = None):
        """
        :param file_name: output file name. If it is not end with h5, the coordinate will be appended to the file name.
        :param with_offset: save the voxel offset or not
        :param with_unique: if this is a segmentation chunk, save the unique object ids or not.
        :param compression: use HDF5 compression or not. Options are gzip, lzf
        """
        if chunk_size:
            assert len(chunk_size) == 3

        if not file_name.endswith('.h5'):
            file_name += self.bbox.to_filename() + '.h5'

        logging.info(f'write chunk to file: {file_name}')
        if os.path.exists(file_name):
            print(yellow(f'deleting existing file: {file_name}'))
            os.remove(file_name)

        with h5py.File(file_name, 'w') as f:
            f.create_dataset('/main',
                             data=self.array,
                             chunks=chunk_size,
                             compression=compression)
            if voxel_size is None and self.voxel_size is not None:
                voxel_size = self.voxel_size
            if voxel_size is not None:
                f.create_dataset('/voxel_size', data=voxel_size)

            if with_offset and self.voxel_offset is not None:
                f.create_dataset('/voxel_offset', data=self.voxel_offset)

            if with_unique and self.is_segmentation:
                unique = np.unique(self.array)
                if unique[0]:
                    unique = unique[1:]
                f.create_dataset('/unique_nonzeros', data=unique)
        return file_name
Ejemplo n.º 7
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    def __call__(self, chunk):
        """ Make part of chunk to be black according to a mask chunk.
        """
        assert isinstance(chunk, Chunk)
        mask_voxel_size = Cartesian.from_collection(
            self.mask_vol.resolution[::-1])
        factor = mask_voxel_size // chunk.voxel_size
        # factor = tuple(m//c for m, c in zip(self.mask_vol.resolution[::-1], chunk.voxel_size))
        for m, c in zip(mask_voxel_size, chunk.voxel_size):
            assert m >= c
            assert m % c == 0

        if np.alltrue(chunk == 0):
            logging.warning("chunk is all black, return directly")
            return chunk

        mask_in_high_mip = self._read_mask_in_high_mip(chunk.bbox, factor)

        if np.alltrue(mask_in_high_mip == 0):
            logging.warning(
                'the mask is all black, mask all the voxels directly')
            np.multiply(chunk, 0, out=chunk)
            return chunk
        if np.all(mask_in_high_mip):
            logging.warning("mask elements are all positive, return directly")
            return chunk

        assert np.any(mask_in_high_mip)

        # make it the same type with input
        mask_in_high_mip = mask_in_high_mip.astype(chunk.dtype)

        for offset in np.ndindex(factor):
            chunk.array[..., np.s_[offset[0]::factor[0]],
                        np.s_[offset[1]::factor[1]],
                        np.s_[offset[2]::factor[2]]] *= mask_in_high_mip

        return chunk
Ejemplo n.º 8
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def test_bounding_box():
    bbox = Bbox.from_delta((1, 3, 2), (64, 32, 8))
    bbox = BoundingBox.from_bbox(bbox)
    assert bbox.start == Cartesian(1, 3, 2)
    assert bbox.stop == Cartesian(65, 35, 10)

    bbox = bbox.clone()
    assert isinstance(bbox, BoundingBox)

    minpt = Cartesian(1, 2, 3)
    maxpt = Cartesian(2, 3, 4)
    bbox = BoundingBox(minpt, maxpt)

    bbox = BoundingBox.from_center(Cartesian(1, 2, 3), 3)
    assert bbox == BoundingBox.from_list([-2, -1, 0, 4, 5, 6])

    bbox = BoundingBox.from_center(Cartesian(1, 2, 3), 3, even_size=False)
    assert bbox == BoundingBox.from_list([-2, -1, 0, 5, 6, 7])
Ejemplo n.º 9
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def test_cartesian():
    assert to_cartesian(None) == None
    ct = (1, 2, 3)
    assert to_cartesian(ct) == Cartesian(1, 2, 3)

    ct = Cartesian(1, 2, 3)
    ct += 2
    assert ct == Cartesian(3, 4, 5)

    ct -= 2
    assert ct == Cartesian(1, 2, 3)

    np.testing.assert_equal(ct.vec, Vec(1, 2, 3))

    ct = Cartesian(3, 4, 5)
    ct = ct // 2
    assert ct == Cartesian(1, 2, 2)

    # note that 2*ct will repeat the elements of ct!
    ct2 = ct * 2
    assert ct2 > ct
    assert ct2 >= ct
    assert ct < ct2
    assert ct <= ct2

    ct3 = ct / 2
    assert ct3 == Cartesian(0.5, 1, 1)

    ct4 = Cartesian.from_collection((1, 2, 3))
    assert ct4 == Cartesian(1, 2, 3)

    assert Cartesian(0, 0, 0) * Cartesian(1, 2, 3) == Cartesian(0, 0, 0)

    assert Cartesian(4, 6, 8) / Cartesian(2, 3, 2) == Cartesian(2, 2, 4)

    assert -Cartesian(1, -2, 3) == Cartesian(-1, 2, -3)
Ejemplo n.º 10
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 def test_read_write_aff(self):
     print('test affinitymap io...')
     arr = np.random.rand(3, 8, 16, 16).astype(np.float32)
     chunk = Chunk(arr, voxel_offset=Cartesian(1, 2, 3))
     read_write_h5(chunk)
Ejemplo n.º 11
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 def test_read_write_image(self):
     print('test image io...')
     arr = np.random.randint(0, 256, size=(8, 16, 16), dtype=np.uint8)
     chunk = Chunk(arr, voxel_offset=Cartesian(1, 2, 3))
     read_write_h5(chunk)
     read_write_tif(chunk)
Ejemplo n.º 12
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    def from_h5(cls,
                file_name: str,
                voxel_offset: tuple = None,
                dataset_path: str = None,
                voxel_size: tuple = None,
                cutout_start: tuple = None,
                cutout_stop: tuple = None,
                cutout_size: tuple = None,
                zero_filling: bool = False,
                dtype: str = None):

        assert os.path.exists(file_name)

        if cutout_start is not None and cutout_size is not None:
            cutout_stop = tuple(t + s
                                for t, s in zip(cutout_start, cutout_size))

        if not h5py.is_hdf5(file_name):
            assert cutout_start is not None
            assert cutout_stop is not None
            bbox = BoundingBox.from_list([*cutout_start, *cutout_stop])
            file_name += f'{bbox.to_filename()}.h5'

            if zero_filling and (not os.path.exists(file_name)
                                 or os.path.getsize(file_name) == 0):
                # fill with zero
                assert dtype is not None
                logging.info(f'{file_name} do not exist, will return None.')
                # return cls.from_bbox(bbox, dtype=dtype, voxel_size=voxel_size, all_zero=True)
                return None

        with h5py.File(file_name, 'r') as f:
            if dataset_path is None:
                for key in f.keys():
                    if 'offset' not in key and 'unique' not in key:
                        # the first name without offset inside
                        dataset_path = key
                        break
            dset = f[dataset_path]
            if voxel_offset is None:
                if 'voxel_offset' in f:
                    voxel_offset = Cartesian(*f['voxel_offset'])
                else:
                    voxel_offset = Cartesian(0, 0, 0)

            if voxel_size is None:
                if 'voxel_size' in f:
                    voxel_size = Cartesian(*f['voxel_size'])
                else:
                    voxel_size = Cartesian(1, 1, 1)

            if cutout_start is None:
                cutout_start = voxel_offset
            if cutout_size is None:
                cutout_size = dset.shape[-3:]
            if cutout_stop is None:
                cutout_stop = tuple(t + s
                                    for t, s in zip(cutout_start, cutout_size))

            for c, v in zip(cutout_start, voxel_offset):
                assert c >= v, "can only cutout after the global voxel offset."

            assert len(cutout_start) == 3
            assert len(cutout_stop) == 3
            dset = dset[..., cutout_start[0] - voxel_offset[0]:cutout_stop[0] -
                        voxel_offset[0], cutout_start[1] -
                        voxel_offset[1]:cutout_stop[1] - voxel_offset[1],
                        cutout_start[2] - voxel_offset[2]:cutout_stop[2] -
                        voxel_offset[2], ]

        logging.info(
            f"""read from HDF5 file: {file_name} and start with {cutout_start}, \
ends with {cutout_stop}, size is {cutout_size}, voxel size is {voxel_size}.""")
        arr = np.asarray(dset)
        if arr.dtype == np.dtype('<f4'):
            arr = arr.astype('float32')
        elif arr.dtype == np.dtype('<f8'):
            arr = arr.astype('float64')

        logging.info(f'new chunk voxel offset: {cutout_start}')

        return cls(arr, voxel_offset=cutout_start, voxel_size=voxel_size)
Ejemplo n.º 13
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    def create(cls,
               size: Cartesian = Cartesian(64, 64, 64),
               dtype: type = np.uint8,
               voxel_offset: Cartesian = Cartesian(0, 0, 0),
               voxel_size: Cartesian = None,
               pattern: str = 'sin',
               high: int = 255):
        """create a fake chunk for tests.

        Args:
            size (tuple, Cartesian, optional): chunk size or shape. Defaults to (64, 64, 64).
            dtype (type, optional): data type like numpy. Defaults to np.uint8.
            voxel_offset (Cartesian, optional): coordinate of starting voxel. Defaults to Cartesian(0, 0, 0).
            voxel_size (Cartesian, optional): physical size of each voxel. Defaults to None.
            pattern (str, optional): ways to create an array. ['sin', 'random', 'zero']. Defaults to 'sin'.
            high (int, optional): the high value of random integer array. Defaults to 255.

        Raises:
            NotImplementedError: not support pattern or data type was used.

        Returns:
            Chunk: the random chunk created.
        """
        # if not isinstance(size, Cartesian):
        #     size = Cartesian.from_collection(size)

        if isinstance(dtype, str):
            dtype = np.dtype(dtype)

        if pattern == 'zero':
            arr = np.zeros(size, dtype=dtype)
        elif pattern == 'sin':
            ix, iy, iz = np.meshgrid(
                *[np.linspace(0, 1, n) for n in size[-3:]], indexing='ij')
            arr = np.abs(np.sin(4 * (ix + iy + iz)))
            if len(size) == 4:
                arr = np.expand_dims(arr, axis=0)
                arr = np.repeat(arr, size[0], axis=0)

            if dtype == np.uint8:
                arr = (arr * 255).astype(dtype)
            elif dtype == np.uint32 or dtype == np.uint64:
                arr = (arr > 0.5).astype(dtype)
                arr = cc3d.connected_components(arr, connectivity=6)
            elif np.issubdtype(dtype, np.floating):
                arr = arr.astype(dtype)
            else:
                raise NotImplementedError(
                    f'do not support this data type: {dtype}')
        elif pattern == 'random':
            if np.issubdtype(dtype, np.floating):
                arr = np.random.rand(*size)
                arr = arr.astype(dtype)
            elif np.issubdtype(dtype, np.integer):
                arr = np.random.randint(high, size=size, dtype=dtype)
                arr = cc3d.connected_components(arr, connectivity=6)
            else:
                raise NotImplementedError(
                    f'do not support this data type: {dtype}')
        else:
            raise NotImplementedError(f'do not support the pattern: {pattern}')

        return cls(arr, voxel_offset=voxel_offset, voxel_size=voxel_size)
Ejemplo n.º 14
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    def __init__(self,
                 convnet_model: Union[str, PatchInferencerBase],
                 convnet_weight_path: str,
                 input_patch_size: Union[tuple, list, Cartesian],
                 output_patch_size: Union[tuple, list, Cartesian] = None,
                 patch_num: Union[tuple, list, Cartesian] = None,
                 num_output_channels: int = 3,
                 output_patch_overlap: Union[tuple, list, Cartesian] = None,
                 output_crop_margin: Union[tuple, list, Cartesian] = None,
                 dtype='float32',
                 framework: str = 'universal',
                 batch_size: int = 1,
                 bump: str = 'wu',
                 input_size: Union[tuple, list, Cartesian] = None,
                 mask_output_chunk: bool = True,
                 mask_myelin_threshold=None,
                 test_time_augmentation: bool = False,
                 dry_run: bool = False):
        """convnet inference patch by patch in a chunk

        Args:
            convnet_model (Union[str, PatchInferencerBase]): the path of convnet model
            convnet_weight_path (str): the path of trained model weights
            input_patch_size (Union[tuple, list, Cartesian]): input patch size, zyx
            output_patch_size (Union[tuple, list, Cartesian], optional): output patch size. Defaults to the same with input patch size.
            patch_num (Union[tuple, list, Cartesian], optional): number of patches. Defaults to be computed.
            num_output_channels (int, optional): number of output channels. Defaults to 3.
            output_patch_overlap (Union[tuple, list, Cartesian], optional): the overlap size of output patch size. Defaults to be half of output patch size.
            output_crop_margin (Union[tuple, list, Cartesian], optional): crop some output patch margin. Defaults to None.
            dtype (str, optional): data type named consistantly with numpy. Defaults to 'float32'.
            framework (str, optional): ['universal', 'identity', 'pytorch']. Defaults to 'universal'.
            batch_size (int, optional): batch size in one pass. this parameter seems do not accelarate computation. Defaults to 1.
            bump (str, optional): bump function. Defaults to 'wu'.
            input_size (Union[tuple, list, Cartesian], optional): input chunk size. Defaults to None.
            mask_output_chunk (bool, optional): normalize on the chunk level rather than patch level. Defaults to True.
            mask_myelin_threshold (_type_, optional): threshold to segment the myelin. Defaults to None.
            test_time_augmentation (bool, optional): augment the image patch, inference, transform back and blend. Defaults to True.
            dry_run (bool, optional): only compute parameters and setup, do not perform any real computation. Defaults to False.
        """
        assert input_size is None or patch_num is None

        if logging.getLogger().getEffectiveLevel() <= 30:
            self.verbose = True
        else:
            self.verbose = False

        input_patch_size = to_cartesian(input_patch_size)
        patch_num = to_cartesian(patch_num)
        input_size = to_cartesian(input_size)
        output_patch_size = to_cartesian(output_patch_size)
        output_patch_overlap = to_cartesian(output_patch_overlap)
        output_crop_margin = to_cartesian(output_crop_margin)

        if output_patch_size is None:
            output_patch_size = input_patch_size

        if output_patch_overlap is None:
            output_patch_overlap = output_patch_size // 2

        self.input_patch_size = input_patch_size
        self.output_patch_size = output_patch_size
        self.output_patch_overlap = output_patch_overlap
        self.patch_num = patch_num
        self.batch_size = batch_size
        self.input_size = input_size

        if output_crop_margin is None:
            if mask_output_chunk:
                self.output_crop_margin = Cartesian(0, 0, 0)
            else:
                self.output_crop_margin = self.output_patch_overlap
        else:
            self.output_crop_margin = output_crop_margin
            # we should always crop more than the patch overlap
            # since the overlap region is reweighted by patch mask
            assert self.output_crop_margin >= self.output_patch_overlap

        # if self.input_patch_size != self.output_patch_size:
        #     breakpoint()
        # self.output_patch_crop_margin = tuple((ips-ops)//2 for ips, ops in zip(
        # input_patch_size, output_patch_size))
        self.output_patch_crop_margin = (input_patch_size -
                                         output_patch_size) // 2

        #self.output_offset = tuple(opcm+ocm for opcm, ocm in zip(
        #    self.output_patch_crop_margin, self.output_crop_margin))
        self.output_offset = self.output_crop_margin

        self.output_patch_stride = tuple(
            s - o for s, o in zip(output_patch_size, output_patch_overlap))

        self.input_patch_overlap = tuple(opcm * 2 + oo for opcm, oo in zip(
            self.output_patch_crop_margin, self.output_patch_overlap))

        self.input_patch_stride = tuple(
            ps - po
            for ps, po in zip(input_patch_size, self.input_patch_overlap))

        # no chunk wise mask, the patches should be aligned inside chunk
        if not mask_output_chunk:
            assert (self.input_size is not None) or (self.patch_num
                                                     is not None)
            if patch_num is None:
                assert input_size is not None
                self.patch_num = tuple((isz - o) // s for isz, o, s in zip(
                    self.input_size, self.input_patch_overlap,
                    self.input_patch_stride))

            if self.input_size is None:
                assert self.patch_num is not None
                self.input_size = tuple(pst * pn + po for pst, pn, po in zip(
                    self.input_patch_stride, self.patch_num,
                    self.input_patch_overlap))

            self.output_size = tuple(
                pst * pn + po - 2 * ocm for pst, pn, po, ocm in zip(
                    self.output_patch_stride, self.patch_num,
                    self.output_patch_overlap, self.output_crop_margin))
        else:
            # we can handle arbitrary input and output size
            self.input_size = None
            self.output_size = None

        self.num_output_channels = num_output_channels
        self.mask_output_chunk = mask_output_chunk
        self.output_chunk_mask = None
        self.dtype = dtype
        self.mask_myelin_threshold = mask_myelin_threshold
        self.dry_run = dry_run

        # allocate a buffer to avoid redundant memory allocation
        self.input_patch_buffer = np.zeros((batch_size, 1, *input_patch_size),
                                           dtype=dtype)

        self.patch_slices_list = []

        if isinstance(convnet_model, str):
            convnet_model = os.path.expanduser(convnet_model)
        if isinstance(convnet_weight_path, str):
            convnet_weight_path = os.path.expanduser(convnet_weight_path)
        self._prepare_patch_inferencer(framework, convnet_model,
                                       convnet_weight_path, bump)

        self.test_time_augmentation = test_time_augmentation
Ejemplo n.º 15
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    def from_dvid_list(cls, syns: list, resolution: Cartesian = None):
        """from a dict fetched from DVID using fivol

        Args:
            syns (list): the synapse list fetched from DVID

        Returns:
            Synapses: a Synapses instance

        Example:
            syns = fivol.get_syndata(dvid_url, uuid)
            synapses = Synapses.from_dvid_list(syns)
        """
        print(f'loading {len(syns)} synapses...')
        pre_list = []
        post_list = []
        pre_confidence = []
        pre_users = []
        for syn in syns:
            if 'Pre' in syn['Kind']:
                # map from xyz to zyx
                pos = syn['Pos'][::-1]
                pos = Cartesian(*pos)
                pre_list.append(pos)

                if 'conf' in syn['Prop']:
                    conf = syn['Prop']['conf']
                    conf = float(conf)
                else:
                    conf = 1.0
                pre_confidence.append(conf)

                user = syn['Prop']['user']
                pre_users.append(user)

        print('loading post synapses...')
        pre_set = set(pre_list)
        post_users = []
        for syn in syns:
            if 'Post' in syn['Kind']:
                # map from xyz to zyx
                pos = syn['Pos'][::-1]
                pos = Cartesian(*pos)
                # if 'To' not in syn['Prop']:
                # print(syn)
                # breakpoint()
                if len(syn['Rels']) > 0:
                    pre_pos = syn['Rels'][0]['To'][::-1]
                    pre_pos = Cartesian(*pre_pos)
                    if pre_pos in pre_set:
                        post_list.append((pos, pre_pos))
                        user = syn['Prop']['user']
                        post_users.append(user)
                    else:
                        print('found a postsynapse with deleted presynapse: ',
                              syn)
                else:
                    print('found an post synapse without presynapse: ', syn)

        # build a map from pre position to index
        pre_pos2idx = {}
        for idx, pos in enumerate(pre_list):
            pre_pos2idx[pos] = idx
        assert len(pre_pos2idx) == len(pre_list)
        # breakpoint()

        post_to_pre_indices = []
        for _, pre_pos in post_list:
            pre_idx = pre_pos2idx[pre_pos]
            post_to_pre_indices.append(pre_idx)
        assert len(post_to_pre_indices) == len(post_list)

        pre = np.asarray(pre_list, dtype=np.int32)
        pre_confidence = np.asarray(pre_confidence, dtype=np.float32)
        post_to_pre_indices = np.asarray(post_to_pre_indices, dtype=np.int32)
        post_list = [x[0] for x in post_list]
        post_list = np.asarray(post_list, dtype=np.int32)
        post_to_pre_indices = np.expand_dims(post_to_pre_indices, 1)
        post = np.hstack((post_to_pre_indices, post_list))

        users = set(pre_users).union(set(post_users))
        users = list(users)
        user2id = {}
        for idx, user in enumerate(users):
            user2id[user] = idx
        for idx, user in enumerate(pre_users):
            pre_users[idx] = user2id[user]
        for idx, user in enumerate(post_users):
            post_users[idx] = user2id[user]

        pre_users = np.asarray(pre_users, dtype=np.int32)
        post_users = np.asarray(post_users, dtype=np.int32)
        return cls(
            pre,
            post=post,
            pre_confidence=pre_confidence,
            resolution=resolution,
            users=users,
            pre_users=pre_users,
            post_users=post_users,
        )