# head opensuse112.iso | hexdump -C | more
00000000  fa 31 ed 8e d5 bc 00 7c  fb fc 66 31 db 66 31 c9  |.1.....|..f1.f1.|
00000010  66 53 66 51 06 57 8e dd  8e c5 52 be 00 7c bf 00  |fSfQ.W....R..|..|
00000020  06 b9 00 01 f3 a5 ea 2b  06 00 00 52 b4 41 bb aa  |.......+...R.A..|
00000030  55 31 c9 30 f6 f9 cd 13  72 16 81 fb 55 aa 75 10  |U1.0....r...U.u.|
00000040  83 e1 01 74 0b 66 c7 06  d1 06 b4 42 eb 15 eb 00  |...t.f.....B....|
00000050  5a 51 b4 08 cd 13 83 e1  3f 5b 51 0f b6 c6 40 50  |ZQ......?[Q...@P|
00000060  f7 e1 53 52 50 bb 00 7c  b9 04 00 66 a1 b0 07 e8  |..SRP..|...f....|
00000070  44 00 0f 82 80 00 66 40  80 c7 02 e2 f2 66 81 3e  |D.....f@.....f.>|
00000080  40 7c fb c0 78 70 75 09  fa bc ec 7b ea 44 7c 00  |@|..xpu....{.D|.|
00000090  00 e8 83 00 69 73 6f 6c  69 6e 75 78 2e 62 69 6e  |....isolinux.bin|
000000a0  20 6d 69 73 73 69 6e 67  20 6f 72 20 63 6f 72 72  | missing or corr|
000000b0  75 70 74 2e 0d 0a 66 60  66 31 d2 66 03 06 f8 7b  |upt...f`f1.f...{|

# head xubu.iso | hexdump -C | more
00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00008000  01 43 44 30 30 31 01 00  4c 49 4e 55 58 20 20 20  |.CD001..LINUX   |
00008010  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
00008020  20 20 20 20 20 20 20 20  43 44 52 4f 4d 20 20 20  |        CDROM   |
00008030  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |