Example #1
0
def register(param, file_src, file_dest, file_mat, file_out, im_mask=None):
    """
    Register two images by estimating slice-wise Tx and Ty transformations, which are regularized along Z. This function
    uses ANTs' isct_antsSliceRegularizedRegistration.

    :param param:
    :param file_src:
    :param file_dest:
    :param file_mat:
    :param file_out:
    :param im_mask: Image of mask, could be 2D or 3D
    :return:
    """

    # TODO: deal with mask

    # initialization
    failed_transfo = 0  # by default, failed matrix is 0 (i.e., no failure)
    do_registration = True

    # get metric radius (if MeanSquares, CC) or nb bins (if MI)
    if param.metric == 'MI':
        metric_radius = '16'
    else:
        metric_radius = '4'
    file_out_concat = file_out

    kw = dict()
    im_data = Image(
        file_src
    )  # TODO: pass argument to use antsReg instead of opening Image each time

    # register file_src to file_dest
    if param.todo == 'estimate' or param.todo == 'estimate_and_apply':
        # If orientation is sagittal, use antsRegistration in 2D mode
        # Note: the parameter --restrict-deformation is irrelevant with affine transfo

        if param.sampling == 'None':
            # 'None' sampling means 'fully dense' sampling
            # see https://github.com/ANTsX/ANTs/wiki/antsRegistration-reproducibility-issues
            sampling = param.sampling
        else:
            # param.sampling should be a float in [0,1], and means the
            # samplingPercentage that chooses a subset of points to
            # estimate from. We always use 'Regular' (evenly-spaced)
            # mode, though antsRegistration offers 'Random' as well.
            # Be aware: even 'Regular' is not fully deterministic:
            # > Regular includes a random perturbation on the grid sampling
            # - https://github.com/ANTsX/ANTs/issues/976#issuecomment-602313884
            sampling = 'Regular,' + param.sampling

        if im_data.orientation[2] in 'LR':
            cmd = [
                'isct_antsRegistration', '-d', '2', '--transform',
                'Affine[%s]' % param.gradStep, '--metric',
                param.metric + '[' + file_dest + ',' + file_src + ',1,' +
                metric_radius + ',' + sampling + ']', '--convergence',
                param.iter, '--shrink-factors', '1', '--smoothing-sigmas',
                param.smooth, '--verbose', '1', '--output',
                '[' + file_mat + ',' + file_out_concat + ']'
            ]
            cmd += get_interpolation('isct_antsRegistration', param.interp)
            if im_mask is not None:
                # if user specified a mask, make sure there are non-null voxels in the image before running the registration
                if np.count_nonzero(im_mask.data):
                    cmd += ['--masks', im_mask.absolutepath]
                else:
                    # Mask only contains zeros. Copying the image instead of estimating registration.
                    copy(file_src, file_out_concat, verbose=0)
                    do_registration = False
                    # TODO: create affine mat file with identity, in case used by -g 2
        # 3D mode
        else:
            cmd = [
                'isct_antsSliceRegularizedRegistration', '--polydegree',
                param.poly, '--transform',
                'Translation[%s]' % param.gradStep, '--metric',
                param.metric + '[' + file_dest + ',' + file_src + ',1,' +
                metric_radius + ',' + sampling + ']', '--iterations',
                param.iter, '--shrinkFactors', '1', '--smoothingSigmas',
                param.smooth, '--verbose', '1', '--output',
                '[' + file_mat + ',' + file_out_concat + ']'
            ]
            cmd += get_interpolation('isct_antsSliceRegularizedRegistration',
                                     param.interp)
            if im_mask is not None:
                cmd += ['--mask', im_mask.absolutepath]
        # run command
        if do_registration:
            kw.update(dict(is_sct_binary=True))
            # reducing the number of CPU used for moco (see issue #201 and #2642)
            env = {
                **os.environ,
                **{
                    "ITK_GLOBAL_DEFAULT_NUMBER_OF_THREADS": "1"
                }
            }
            status, output = run_proc(cmd,
                                      verbose=1 if param.verbose == 2 else 0,
                                      env=env,
                                      **kw)

    elif param.todo == 'apply':
        sct_apply_transfo.main(argv=[
            '-i', file_src, '-d', file_dest, '-w', file_mat + param.suffix_mat,
            '-o', file_out_concat, '-x', param.interp, '-v', '0'
        ])

    # check if output file exists
    # Note (from JCA): In the past, i've tried to catch non-zero output from ANTs function (via the 'status' variable),
    # but in some OSs, the function can fail while outputing zero. So as a pragmatic approach, I decided to go with
    # the "output file checking" approach, which is 100% sensitive.
    if not os.path.isfile(file_out_concat):
        # printv(output, verbose, 'error')
        printv(
            'WARNING in ' + os.path.basename(__file__) +
            ': No output. Maybe related to improper calculation of '
            'mutual information. Either the mask you provided is '
            'too small, or the subject moved a lot. If you see too '
            'many messages like this try with a bigger mask. '
            'Using previous transformation for this volume (if it'
            'exists).', param.verbose, 'warning')
        failed_transfo = 1

    # If sagittal, copy header (because ANTs screws it) and add singleton in 3rd dimension (for z-concatenation)
    if im_data.orientation[2] in 'LR' and do_registration:
        im_out = Image(file_out_concat)
        im_out.header = im_data.header
        im_out.data = np.expand_dims(im_out.data, 2)
        im_out.save(file_out, verbose=0)

    # return status of failure
    return failed_transfo
    def apply(self):
        # Initialization
        fname_src = self.input_filename  # source image (moving)
        list_warp = self.list_warp  # list of warping fields
        fname_out = self.output_filename  # output
        fname_dest = self.fname_dest  # destination image (fix)
        verbose = self.verbose
        remove_temp_files = self.remove_temp_files
        crop_reference = self.crop  # if = 1, put 0 everywhere around warping field, if = 2, real crop

        islabel = False
        if self.interp == 'label':
            islabel = True
            self.interp = 'nn'

        interp = get_interpolation('isct_antsApplyTransforms', self.interp)

        # Parse list of warping fields
        printv('\nParse list of warping fields...', verbose)
        use_inverse = []
        fname_warp_list_invert = []
        # list_warp = list_warp.replace(' ', '')  # remove spaces
        # list_warp = list_warp.split(",")  # parse with comma
        for idx_warp, path_warp in enumerate(self.list_warp):
            # Check if this transformation should be inverted
            if path_warp in self.list_warpinv:
                use_inverse.append('-i')
                # list_warp[idx_warp] = path_warp[1:]  # remove '-'
                fname_warp_list_invert += [[
                    use_inverse[idx_warp], list_warp[idx_warp]
                ]]
            else:
                use_inverse.append('')
                fname_warp_list_invert += [[path_warp]]
            path_warp = list_warp[idx_warp]
            if path_warp.endswith((".nii", ".nii.gz")) \
                    and Image(list_warp[idx_warp]).header.get_intent()[0] != 'vector':
                raise ValueError(
                    "Displacement field in {} is invalid: should be encoded"
                    " in a 5D file with vector intent code"
                    " (see https://nifti.nimh.nih.gov/pub/dist/src/niftilib/nifti1.h"
                    .format(path_warp))
        # need to check if last warping field is an affine transfo
        isLastAffine = False
        path_fname, file_fname, ext_fname = extract_fname(
            fname_warp_list_invert[-1][-1])
        if ext_fname in ['.txt', '.mat']:
            isLastAffine = True

        # check if destination file is 3d
        # check_dim(fname_dest, dim_lst=[3]) # PR 2598: we decided to skip this line.

        # N.B. Here we take the inverse of the warp list, because sct_WarpImageMultiTransform concatenates in the reverse order
        fname_warp_list_invert.reverse()
        fname_warp_list_invert = functools.reduce(lambda x, y: x + y,
                                                  fname_warp_list_invert)

        # Extract path, file and extension
        path_src, file_src, ext_src = extract_fname(fname_src)
        path_dest, file_dest, ext_dest = extract_fname(fname_dest)

        # Get output folder and file name
        if fname_out == '':
            path_out = ''  # output in user's current directory
            file_out = file_src + '_reg'
            ext_out = ext_src
            fname_out = os.path.join(path_out, file_out + ext_out)

        # Get dimensions of data
        printv('\nGet dimensions of data...', verbose)
        img_src = Image(fname_src)
        nx, ny, nz, nt, px, py, pz, pt = img_src.dim
        # nx, ny, nz, nt, px, py, pz, pt = get_dimension(fname_src)
        printv(
            '  ' + str(nx) + ' x ' + str(ny) + ' x ' + str(nz) + ' x ' +
            str(nt), verbose)

        # if 3d
        if nt == 1:
            # Apply transformation
            printv('\nApply transformation...', verbose)
            if nz in [0, 1]:
                dim = '2'
            else:
                dim = '3'
            # if labels, dilate before resampling
            if islabel:
                printv("\nDilate labels before warping...")
                path_tmp = tmp_create(basename="apply_transfo")
                fname_dilated_labels = os.path.join(path_tmp,
                                                    "dilated_data.nii")
                # dilate points
                dilate(Image(fname_src), 4, 'ball').save(fname_dilated_labels)
                fname_src = fname_dilated_labels

            printv(
                "\nApply transformation and resample to destination space...",
                verbose)
            run_proc([
                'isct_antsApplyTransforms', '-d', dim, '-i', fname_src, '-o',
                fname_out, '-t'
            ] + fname_warp_list_invert + ['-r', fname_dest] + interp,
                     is_sct_binary=True)

        # if 4d, loop across the T dimension
        else:
            if islabel:
                raise NotImplementedError

            dim = '4'
            path_tmp = tmp_create(basename="apply_transfo")

            # convert to nifti into temp folder
            printv('\nCopying input data to tmp folder and convert to nii...',
                   verbose)
            img_src.save(os.path.join(path_tmp, "data.nii"))
            copy(fname_dest, os.path.join(path_tmp, file_dest + ext_dest))
            fname_warp_list_tmp = []
            for fname_warp in list_warp:
                path_warp, file_warp, ext_warp = extract_fname(fname_warp)
                copy(fname_warp, os.path.join(path_tmp, file_warp + ext_warp))
                fname_warp_list_tmp.append(file_warp + ext_warp)
            fname_warp_list_invert_tmp = fname_warp_list_tmp[::-1]

            curdir = os.getcwd()
            os.chdir(path_tmp)

            # split along T dimension
            printv('\nSplit along T dimension...', verbose)

            im_dat = Image('data.nii')
            im_header = im_dat.hdr
            data_split_list = sct_image.split_data(im_dat, 3)
            for im in data_split_list:
                im.save()

            # apply transfo
            printv('\nApply transformation to each 3D volume...', verbose)
            for it in range(nt):
                file_data_split = 'data_T' + str(it).zfill(4) + '.nii'
                file_data_split_reg = 'data_reg_T' + str(it).zfill(4) + '.nii'

                status, output = run_proc([
                    'isct_antsApplyTransforms',
                    '-d',
                    '3',
                    '-i',
                    file_data_split,
                    '-o',
                    file_data_split_reg,
                    '-t',
                ] + fname_warp_list_invert_tmp + [
                    '-r',
                    file_dest + ext_dest,
                ] + interp,
                                          verbose,
                                          is_sct_binary=True)

            # Merge files back
            printv('\nMerge file back...', verbose)
            import glob
            path_out, name_out, ext_out = extract_fname(fname_out)
            # im_list = [Image(file_name) for file_name in glob.glob('data_reg_T*.nii')]
            # concat_data use to take a list of image in input, now takes a list of file names to open the files one by one (see issue #715)
            fname_list = glob.glob('data_reg_T*.nii')
            fname_list.sort()
            im_list = [Image(fname) for fname in fname_list]
            im_out = sct_image.concat_data(im_list, 3, im_header['pixdim'])
            im_out.save(name_out + ext_out)

            os.chdir(curdir)
            generate_output_file(os.path.join(path_tmp, name_out + ext_out),
                                 fname_out)
            # Delete temporary folder if specified
            if remove_temp_files:
                printv('\nRemove temporary files...', verbose)
                rmtree(path_tmp, verbose=verbose)

        # Copy affine matrix from destination space to make sure qform/sform are the same
        printv(
            "Copy affine matrix from destination space to make sure qform/sform are the same.",
            verbose)
        im_src_reg = Image(fname_out)
        im_src_reg.copy_qform_from_ref(Image(fname_dest))
        im_src_reg.save(
            verbose=0
        )  # set verbose=0 to avoid warning message about rewriting file

        if islabel:
            printv(
                "\nTake the center of mass of each registered dilated labels..."
            )
            labeled_img = cubic_to_point(im_src_reg)
            labeled_img.save(path=fname_out)
            if remove_temp_files:
                printv('\nRemove temporary files...', verbose)
                rmtree(path_tmp, verbose=verbose)

        # Crop the resulting image using dimensions from the warping field
        warping_field = fname_warp_list_invert[-1]
        # If the last transformation is not an affine transfo, we need to compute the matrix space of the concatenated
        # warping field
        if not isLastAffine and crop_reference in [1, 2]:
            printv('Last transformation is not affine.')
            if crop_reference in [1, 2]:
                # Extract only the first ndim of the warping field
                img_warp = Image(warping_field)
                if dim == '2':
                    img_warp_ndim = Image(img_src.data[:, :], hdr=img_warp.hdr)
                elif dim in ['3', '4']:
                    img_warp_ndim = Image(img_src.data[:, :, :],
                                          hdr=img_warp.hdr)
                # Set zero to everything outside the warping field
                cropper = ImageCropper(Image(fname_out))
                cropper.get_bbox_from_ref(img_warp_ndim)
                if crop_reference == 1:
                    printv(
                        'Cropping strategy is: keep same matrix size, put 0 everywhere around warping field'
                    )
                    img_out = cropper.crop(background=0)
                elif crop_reference == 2:
                    printv(
                        'Cropping strategy is: crop around warping field (the size of warping field will '
                        'change)')
                    img_out = cropper.crop()
                img_out.save(fname_out)

        display_viewer_syntax([fname_dest, fname_out], verbose=verbose)