diff --git a/transform.py b/transform.py
new file mode 100644
index 0000000..c863e68
--- /dev/null
+++ b/transform.py
@@ -0,0 +1,101 @@
+import geometa
+
+
+# This function checks if a valid filename has been provided
+def check_invalid_filename(filename):
+
+    # List of valid filetypes
+    valid_filetypes = [
+                   'gen', 'thf', 'adf', 'blx', 'xlb', 'bag', 'bmp', 'kap',
+                   'bt', 'doq', 'dt0', 'dt1', 'dt2', 'ers', 'n1', 'fits',
+                   'hdr', 'gif', 'grb', 'tif', 'img', 'mpr', 'mpl', 'mem',
+                   'jpg', 'jp2', 'j2k', 'ntf', 'nsf', 'grc', 'tab', 'grd',
+                   'png', 'ppm', 'pgm', 'prf', 'rik', 'rsw', 'mtw', 'xml',
+                   'safe', 'ter', 'TIL', 'vrt', 'xpm']
+
+    invalid = False
+
+    # Check the input is a file
+    if '.' not in filename:
+        print('\n\nThat is not a file.')
+        invalid = True
+
+    # If it is a file check it's a valid file type
+    else:
+        filetype = filename[filename.rfind('.')+1:]
+        if filetype not in valid_filetypes:
+            invalid = True
+            print('\n\nInvalid filetype. Your filetype is ', filetype,
+                  '.\n\nValid filetypes are:', '\n\n', valid_filetypes)
+
+    return invalid
+
+
+# ________________________________________________
+
+
+# This function checks if the doi the user has supplied is invalid
+def check_invalid_doi(doi):
+
+    if ('10.' not in doi) or ('/' not in doi):
+        print('\n\nThat is an invalid doi, please supply a valid doi.')
+        invalid = True
+    else:
+        invalid = False
+
+    return invalid
+
+# ________________________________________________
+
+
+def info_from_user():
+    '''
+    This function asks the user for:
+    -The name of the file to be converted
+    -The doi of the dataset
+    -The doi of the publication
+
+    It also sanity-checks the supplied information e.g. valid filetype,
+    and keeps asking until a reasonable answer has been provided.
+    '''
+    # Ask the user for their filename
+    # Keep asking until a valid file has been given
+
+    ask = True
+    while ask:
+
+        # Get name from user
+        filename = input('Input the filename: ')
+
+        ask = check_invalid_filename(filename)
+
+    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    # Ask the user for the doi of their dataset
+    # Keep asking until a valid doi has been given
+    ask = True
+    while ask:
+
+        # Get doi from user
+        doi_dataset = input('Input the dataset doi: ')
+        ask = check_invalid_doi(doi_dataset)
+
+    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    # Ask the user for the doi of their publication
+    # Keep asking until a valid doi has been given
+    ask = True
+    while ask:
+
+        # Get doi from user
+        doi_pub = input('Input the publication doi: ')
+        ask = check_invalid_doi(doi_pub)
+
+    return filename, doi_dataset, doi_pub
+
+
+if __name__ == "__main__":
+    # Get required information from the user.
+    filename, doi_dataset, doi_pub = info_from_user()
+    output_filename = "output.json"
+    geometa.get_meta(filename, doi_dataset, doi_pub, output_filename)