QD: Re-indent mk_qd script and add new parameter to round up byte values to block size.

Author: keirf

scripts/mk_qd.py

@@ -9,41 +9,59 @@
 
 import sys,struct,argparse
 
+def round_up(x, y):
+    return (x + y - 1) & ~(y - 1)
+
 def main(argv):
-  parser = argparse.ArgumentParser(
-    formatter_class=argparse.ArgumentDefaultsHelpFormatter)
-  parser.add_argument("--lead-in", type=float, default=0.5,
-                      help="lead-in, seconds")
-  parser.add_argument("--window", type=float, default=5.5,
-                      help="data window, seconds")
-  parser.add_argument("--total", type=float, default=8.0,
-                      help="total length, seconds")
-  parser.add_argument("outfile", help="output filename")
-  args = parser.parse_args(argv[1:])
-
-  bit_ms = 0.004916
-  total_bytes = int(args.total * 1000.0 / bit_ms / 8)
-  window_bytes = int(args.window * 1000.0 / bit_ms / 8)
-  init_bytes = int(args.lead_in * 1000.0 / bit_ms / 8)
-
-  assert (2*init_bytes + window_bytes) < total_bytes, "Window too large"
-  print("Lead-In: %.2f sec -> %u bytes" % (args.lead_in, init_bytes))
-  print("Window:  %.2f sec -> %u bytes" % (args.window, window_bytes))
-  print("TOTAL:   %.2f sec -> %u bytes" % (args.total, total_bytes))
-
-  # Header
-  out_f = open(args.outfile, "wb")
-  out_f.write(struct.pack("<3x2s3x", b"QD"))
-  out_f.write(bytearray(b'\x00'*(512-8)))
-
-  # Track
-  out_f.write(struct.pack("<4I", 1024, total_bytes, init_bytes,
-                          init_bytes + window_bytes))
-  out_f.write(bytearray(b'\x00'*(512-16)))
-
-  # Data
-  blocks = (total_bytes + 511) // 512
-  out_f.write(bytearray(b'\x11'*(blocks*512)))
+    parser = argparse.ArgumentParser(
+      formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+    parser.add_argument("--lead-in", type=float, default=0.5,
+                        help="lead-in, seconds")
+    parser.add_argument("--window", type=float, default=5.5,
+                        help="data window, seconds")
+    parser.add_argument("--total", type=float, default=8.0,
+                        help="total length, seconds")
+    parser.add_argument("--round", action="store_true",
+                        help="round values up to 512-byte block size")
+    parser.add_argument("outfile", help="output filename")
+    args = parser.parse_args(argv[1:])
+
+    lead_in, window, total = args.lead_in, args.window, args.total
+
+    assert lead_in >= 0.1, "Insufficient lead-in"
+    assert total - window - lead_in >= 0.1, "Insufficient lead-out"
+
+    bit_ms = 0.004916
+    total_bytes = int(total * 1000.0 / bit_ms / 8)
+    window_bytes = int(window * 1000.0 / bit_ms / 8)
+    init_bytes = int(lead_in * 1000.0 / bit_ms / 8)
+
+    if args.round:
+        total_bytes = round_up(total_bytes, 512)
+        window_bytes = round_up(window_bytes, 512)
+        init_bytes = round_up(init_bytes, 512)
+
+    print("Lead-In: %.2f sec -> %u bytes" % (lead_in, init_bytes))
+    print("Window:  %.2f sec -> %u bytes" % (window, window_bytes))
+    print("TOTAL:   %.2f sec -> %u bytes" % (total, total_bytes))
+
+    # Header
+    out_f = open(args.outfile, "wb")
+    out_f.write(struct.pack("<3x2s3x", b"QD"))
+    out_f.write(bytearray(b'\x00'*(512-8)))
+
+    # Track
+    out_f.write(struct.pack("<4I", 1024, total_bytes, init_bytes,
+                            init_bytes + window_bytes))
+    out_f.write(bytearray(b'\x00'*(512-16)))
+
+    # Data
+    blocks = (total_bytes + 511) // 512
+    out_f.write(bytearray(b'\x11'*(blocks*512)))
 
 if __name__ == "__main__":
     main(sys.argv)
+
+# Local variables:
+# python-indent: 4
+# End: