Initial commit.

reinterleave.py

@@ -0,0 +1,71 @@
+#!/usr/bin/env python3
+
+import argparse
+
+
+def list_to_dict(l):
+    return { i: l[i] for i in range(len(l)) }
+
+def invert_dict(d):
+    return { v: k for k, v in d.items() }
+
+def compose_dict(d1, d2):
+    return { k: d2[v] for k, v in d1.items() }
+
+
+def reinterleave(src_image, src_interleave, dest_interleave):
+    map = compose_dict(src_interleave, invert_dict(dest_interleave))
+    dest_image = bytearray(len(src_image))
+    for t in range(35):
+        for ss in range(16):
+            src_offset = (t * 16 + ss) * 256
+            dest_offset = (t * 16 + map[ss]) * 256
+            dest_image[dest_offset:dest_offset+256] = src_image[src_offset:src_offset+256]
+    return dest_image
+
+
+half_block_to_phys_sect = list_to_dict([0x00, 0x02, 0x04, 0x06,
+                                        0x08, 0x0a, 0x0c, 0x0e,
+                                        0x01, 0x03, 0x05, 0x07,
+                                        0x09, 0x0b, 0x0d, 0x0f])
+
+dos_to_phys_sect = list_to_dict([0x0, 0xd, 0xb, 0x9, 0x7, 0x5, 0x3, 0x1,
+                                 0xe, 0xc, 0xa, 0x8, 0x6, 0x4, 0x2, 0xf])
+
+identity = { k: k for k in range(16) }
+
+
+
+interleave_tables = { 'dos':    dos_to_phys_sect,
+                      'do':     dos_to_phys_sect,
+                      'pascal': half_block_to_phys_sect,
+                      'phys':   identity,
+                      'po':     half_block_to_phys_sect,
+                      'prodos': half_block_to_phys_sect,
+                      'sos':    half_block_to_phys_sect }
+
+
+parser = argparse.ArgumentParser()
+
+parser.add_argument('infmt',
+                    type = str,
+                    choices = sorted(interleave_tables.keys()))
+
+parser.add_argument('infile',
+                    type = argparse.FileType('rb'))
+
+parser.add_argument('outfmt',
+                    type = str,
+                    choices = sorted(interleave_tables.keys()))
+
+parser.add_argument('outfile',
+                    type = argparse.FileType('wb'))
+
+args = parser.parse_args()
+
+input_image = args.infile.read()
+
+output_image = reinterleave(input_image, interleave_tables[args.infmt], interleave_tables[args.outfmt])
+
+args.outfile.write(output_image)
+