NF nib-diff

.travis.yml

@@ -14,7 +14,7 @@ cache:
     - $HOME/.cache/pip
 env:
     global:
-        - DEPENDS="six numpy scipy matplotlib h5py pillow pydicom"
+        - DEPENDS="six numpy scipy matplotlib h5py pillow pydicom hypothesis"
         - OPTIONAL_DEPENDS=""
         - INSTALL_TYPE="setup"
         - EXTRA_WHEELS="https://5cf40426d9f06eb7461d-6fe47d9331aba7cd62fc36c7196769e4.ssl.cf2.rackcdn.com"
@@ -95,7 +95,7 @@ before_install:
     - source venv/bin/activate
     - python --version # just to check
     - pip install -U pip wheel  # needed at one point
-    - retry pip install nose flake8 mock  # always
+    - retry pip install nose flake8 mock hypothesis  # always
     - pip install $EXTRA_PIP_FLAGS $DEPENDS $OPTIONAL_DEPENDS
     - if [ "${COVERAGE}" == "1" ]; then
       pip install coverage;

appveyor.yml

@@ -20,8 +20,7 @@ install:
   - SET PATH=%PYTHON%;%PYTHON%\Scripts;%PATH%
 
   # Install the dependencies of the project.
-  - pip install numpy scipy matplotlib nose h5py mock
-  - pip install pydicom
+  - pip install numpy scipy matplotlib nose h5py mock hypothesis pydicom
   - pip install .
   - SET NIBABEL_DATA_DIR=%CD%\nibabel-data
 

bin/nib-diff

@@ -0,0 +1,17 @@
+#!python
+# emacs: -*- mode: python-mode; py-indent-offset: 4; indent-tabs-mode: nil -*-
+# vi: set ft=python sts=4 ts=4 sw=4 et:
+### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ##
+#
+#   See COPYING file distributed along with the NiBabel package for the
+#   copyright and license terms.
+#
+### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ##
+"""
+Quick diff summary for a set of neuroimaging files
+"""
+
+from nibabel.cmdline.diff import main
+
+if __name__ == '__main__':
+    main()

dev-requirements.txt

@@ -2,3 +2,4 @@
 -r requirements.txt
 nose
 mock
+hypothesis

nibabel/cmdline/diff.py

@@ -0,0 +1,207 @@
+#!python
+# emacs: -*- mode: python-mode; py-indent-offset: 4; indent-tabs-mode: nil -*-
+# vi: set ft=python sts=4 ts=4 sw=4 et:
+### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ##
+#
+#   See COPYING file distributed along with the NiBabel package for the
+#   copyright and license terms.
+#
+### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ##
+"""
+Quick summary of the differences among a set of neuroimaging files
+"""
+from __future__ import division, print_function, absolute_import
+
+import re
+import sys
+from collections import OrderedDict
+from optparse import OptionParser, Option
+
+import numpy as np
+
+import nibabel as nib
+import nibabel.cmdline.utils
+import hashlib
+import os
+
+
+def get_opt_parser():
+    # use module docstring for help output
+    p = OptionParser(
+        usage="%s [OPTIONS] [FILE ...]\n\n" % sys.argv[0] + __doc__,
+        version="%prog " + nib.__version__)
+
+    p.add_options([
+        Option("-v", "--verbose", action="count",
+               dest="verbose", default=0,
+               help="Make more noise.  Could be specified multiple times"),
+
+        Option("-H", "--header-fields",
+               dest="header_fields", default='all',
+               help="Header fields (comma separated) to be printed as well (if present)"),
+    ])
+
+    return p
+
+
+def are_values_different(*values):
+    """Generically compares values, returns true if different"""
+    value0 = values[0]
+    values = values[1:]  # to ensure that the first value isn't compared with itself
+
+    for value in values:
+        try:  # we sometimes don't want NaN values
+            if np.any(np.isnan(value0)) and np.any(np.isnan(value)):  # if they're both NaN
+                break
+            elif np.any(np.isnan(value0)) or np.any(np.isnan(value)):  # if only 1 is NaN
+                return True
+
+        except TypeError:
+            pass
+
+        if type(value0) != type(value):  # if types are different, then we consider them different
+            return True
+        elif isinstance(value0, np.ndarray):
+            return np.any(value0 != value)
+
+        elif value0 != value:
+            return True
+
+    return False
+
+
+def get_headers_diff(file_headers, names=None):
+    """Get difference between headers
+
+    Parameters
+    ----------
+    file_headers: list of actual headers (dicts) from files
+    names: list of header fields to test
+
+    Returns
+    -------
+    dict
+      str: list for each header field which differs, return list of
+      values per each file
+    """
+    difference = OrderedDict()
+    fields = names
+
+    if names is None:
+        fields = file_headers[0].keys()
+
+    # for each header field
+    for field in fields:
+        values = [header.get(field) for header in file_headers]  # get corresponding value
+
+        # if these values are different, store them in a dictionary
+        if are_values_different(*values):
+            difference[field] = values
+
+    return difference
+
+
+def get_data_diff(files):
+    """Get difference between md5 values
+
+        Parameters
+        ----------
+        files: list of actual files
+
+        Returns
+        -------
+        list
+          np.array: md5 values of respective files
+        """
+
+    md5sums = [
+        hashlib.md5(np.ascontiguousarray(nib.load(f).get_data(), dtype=np.float32)).hexdigest()
+        for f in files
+    ]
+
+    if len(set(md5sums)) == 1:
+        return []
+
+    return md5sums
+
+
+def display_diff(files, diff):
+    """Format header differences into a nice string
+
+        Parameters
+        ----------
+        files: list of files that were compared so we can print their names
+        diff: dict of different valued header fields
+
+        Returns
+        -------
+        str
+          string-formatted table of differences
+    """
+    output = ""
+    field_width = "{:<15}"
+    value_width = "{:<55}"
+
+    output += "These files are different.\n"
+    output += field_width.format('Field')
+
+    for f in files:
+        output += value_width.format(os.path.basename(f))
+
+    output += "\n"
+
+    for key, value in diff.items():
+        output += field_width.format(key)
+
+        for item in value:
+            item_str = str(item)
+            # Value might start/end with some invisible spacing characters so we
+            # would "condition" it on both ends a bit
+            item_str = re.sub('^[ \t]+', '<', item_str)
+            item_str = re.sub('[ \t]+$', '>', item_str)
+            # and also replace some other invisible symbols with a question
+            # mark
+            item_str = re.sub('[\x00]', '?', item_str)
+            output += value_width.format(item_str)
+
+        output += "\n"
+
+    return output
+
+
+def main(args=None, out=None):
+    """Getting the show on the road"""
+    out = out or sys.stdout
+    parser = get_opt_parser()
+    (opts, files) = parser.parse_args(args)
+
+    nibabel.cmdline.utils.verbose_level = opts.verbose
+
+    if nibabel.cmdline.utils.verbose_level < 3:
+        # suppress nibabel format-compliance warnings
+        nib.imageglobals.logger.level = 50
+
+    assert len(files) >= 2, "Please enter at least two files"
+
+    file_headers = [nib.load(f).header for f in files]
+
+    # signals "all fields"
+    if opts.header_fields == 'all':
+        # TODO: header fields might vary across file types, thus prior sensing would be needed
+        header_fields = file_headers[0].keys()
+    else:
+        header_fields = opts.header_fields.split(',')
+
+    diff = get_headers_diff(file_headers, header_fields)
+    data_diff = get_data_diff(files)
+
+    if data_diff:
+        diff['DATA(md5)'] = data_diff
+
+    if diff:
+        out.write(display_diff(files, diff))
+        raise SystemExit(1)
+
+    else:
+        out.write("These files are identical.\n")
+        raise SystemExit(0)