Add support for renaming algs in bob pad cross

bob/pad/base/script/cross.py

 """Prints Cross-db metrics analysis
 """
 import click
+import json
 import jinja2
 import logging
 import math
@@ -20,8 +21,8 @@ logger = logging.getLogger(__name__)
 
 @click.command(epilog='''\b
 Examples:
-
-  $ bin/bob pad cross 'results/{{ evaluation.database }}/{{ algorithm }}/{{ evaluation.protocol }}/scores/scores-{{ group }}' -td replaymobile -d replaymobile -p grandtest -d oulunpu -p Protocol_1 \
+  $ bin/bob pad cross 'results/{{ evaluation.database }}/{{ algorithm }}/{{ evaluation.protocol }}/scores/scores-{{ group }}' \
+    -td replaymobile -d replaymobile -p grandtest -d oulunpu -p Protocol_1 \
     -a replaymobile_frame-diff-svm \
     -a replaymobile_qm-svm-64 \
     -a replaymobile_lbp-svm-64 \
@@ -37,6 +38,10 @@ Examples:
 @click.option('-a', '--algorithm', 'algorithms', multiple=True, required=True,
               show_default=True,
               help='Names of the algorithms')
+@click.option('-n', '--names', type=click.File('r'),
+              help='Name of algorithms to show in the table. Provide a path '
+              'to a json file maps algorithm names to names that you want to '
+              'see in the table.')
 @click.option('-td', '--train-database', required=True,
               help='The database that was used to train the algorithms.')
 @click.option('-g', '--group', 'groups', multiple=True, show_default=True,
@@ -47,11 +52,13 @@ Examples:
 @verbosity_option()
 @click.pass_context
 def cross(ctx, score_jinja_template, databases, protocols, algorithms,
-          train_database, groups, sort, **kwargs):
+          names, train_database, groups, sort, **kwargs):
     """Cross-db analysis metrics
     """
     log_parameters(logger)
 
+    names = {} if names is None else json.load(names)
+
     env = jinja2.Environment(undefined=jinja2.StrictUndefined)
 
     data = {
@@ -89,7 +96,11 @@ def cross(ctx, score_jinja_template, databases, protocols, algorithms,
         if group == 'eval':
             threshold = metrics[(database, protocol, algorithm, 'dev')][1]
         else:
-            threshold = eer_threshold(neg, pos)
+            try:
+                threshold = eer_threshold(neg, pos)
+            except RuntimeError:
+                logger.error("Something wrong with {}".format(score_path))
+                raise
 
         far, frr = farfrr(neg, pos, threshold)
         hter = (far + frr) / 2
@@ -117,7 +128,10 @@ def cross(ctx, score_jinja_template, databases, protocols, algorithms,
         algorithms = sorted(algorithms, key=sort_key)
 
     for algorithm in algorithms:
-        rows.append([algorithm.replace(train_database + '_', '').replace(train_protocol + '_', '')])
+        name = algorithm.replace(train_database + '_', '')
+        name = name.replace(train_protocol + '_', '')
+        name = names.get(name, name)
+        rows.append([name])
         for database, protocol in zip(databases, protocols):
             cell = []
             for group in groups: