diff --git a/bin/fpfs_img2cat.py b/bin/fpfs_img2cat.py
new file mode 100755
index 0000000..b797f7a
--- /dev/null
+++ b/bin/fpfs_img2cat.py
@@ -0,0 +1,64 @@
+#!/usr/bin/env python
+#
+# FPFS shear estimator
+# Copyright 20221013 Xiangchong Li.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+
+import schwimmbad
+from argparse import ArgumentParser
+from configparser import ConfigParser, ExtendedInterpolation
+from fpfs.tasks import ProcessSimulationTask
+
+
+if __name__ == "__main__":
+    parser = ArgumentParser(description="fpfs measurement")
+    parser.add_argument(
+        "--config",
+        required=True,
+        type=str,
+        help="configure file name",
+    )
+    parser.add_argument(
+        "--min_id",
+        required=True,
+        type=int,
+        help="minimum ID, e.g. 0",
+    )
+    parser.add_argument(
+        "--max_id",
+        required=True,
+        type=int,
+        help="maximum ID, e.g. 4000",
+    )
+    group = parser.add_mutually_exclusive_group()
+    group.add_argument(
+        "--ncores",
+        dest="n_cores",
+        default=1,
+        type=int,
+        help="Number of processes (uses multiprocessing).",
+    )
+    group.add_argument(
+        "--mpi",
+        dest="mpi",
+        default=False,
+        action="store_true",
+        help="Run with MPI.",
+    )
+    args = parser.parse_args()
+    pool = schwimmbad.choose_pool(mpi=args.mpi, processes=args.n_cores)
+    worker = ProcessSimulationTask(args.config)
+    refs = list(range(args.min_id, args.max_id))
+    for r in pool.map(worker.run, refs):
+        pass
+    pool.close()