Add a script to extract a contiguous range of entries from a .bin file.

script/extract_bin.py

@@ -0,0 +1,42 @@
+import sys
+
+ENTRY_SIZE = 40
+NUM_ENTRIES_IN_CHUNK = 1024*1024
+
+def copy(infile, outfile, count, times):
+    if times > 1:
+        outfile.write(infile.read(count*ENTRY_SIZE)*times)
+    else:
+        offset = 0
+        while offset < count:
+            to_read = NUM_ENTRIES_IN_CHUNK if offset + NUM_ENTRIES_IN_CHUNK <= count else count - offset
+
+            outfile.write(infile.read(to_read*ENTRY_SIZE))
+
+            offset += NUM_ENTRIES_IN_CHUNK
+
+def work():
+    filename = sys.argv[1]
+    offset = int(sys.argv[2])
+    count = int(sys.argv[3])
+    times = int(sys.argv[4]) if len(sys.argv) >= 5 else 1
+
+    with open(filename, 'rb') as infile:
+        infile.seek(offset * ENTRY_SIZE)
+        filename_parts = filename.split('.')
+        out_path = '.'.join(filename_parts[:-1]) + '_' + str(offset) + '_' + str(count) + '_' + str(times) + '.' + filename_parts[-1]
+        with open(out_path, 'wb') as outfile:
+            copy(infile, outfile, count, times)
+
+def show_help():
+    print('Usage: python extract_bin.py filename offset count [times]')
+    print('filename - the path to the .bin file to process')
+    print('offset - the number of sfens to skip')
+    print('count - the number of sfens to extract')
+    print('times - the number of times to repeat the extracted sfens. Default = 1')
+    print('The result is saved in a new file named `filename.stem`_`offset`_`count`_`times`.bin')
+
+if len(sys.argv) < 4:
+    show_help()
+else:
+    work()