Cell Duration (BCD) Formula

[kikatu]

Hi:

How can the “cell elapsed time (BCD)” values be calculated, already knowing the playback time (hh:mm:ss:ff) of the whole cell\each Navigation Pack in the Chapter?

[r0lZ]

It's very simple.

The BCD time is 4 bytes long.
The first (most significant) byte is the number of hours.
The second the number of minutes
The third the number of seconds.
The 6 lower bits (bits 5 - 0) of the fourth (less significant) byte is the number of frames.
The two upper bits of the fourth byte indicates the frame rate: 11 is 30 fps and 01 is 25 fps. In other words, bit 7 is the NTSC flag, and bit 6 is always set.

So, 01:02:03:04 PAL is 0x01020344, and in NTSC it's 0x010203C4.

[kikatu]

Thanks r0lZ:

E.g. 00:06:17.00 = 399296 (value in VobEdit) & 00:06:19.18 =?

[bigotti5]

E.g. 00:06:17.00 = 399296 (value in VobEdit) & 00:06:19.18 =?

0x619D8 = 399832

NTSC
22481378 = Hex 15709E2 = 1h 57min 09 sek 22 Frames
22481362 = Hex 15709D2 = 1h 57min 09 sek 12 Frames
22481346 = Hex 15709C2 = 1h 57min 09 sek 02 Frames
PAL
2403 = Hex 963 = 09 sek 23 Frames
2387 = Hex 953 = 09 sek 13 Frames
2371 = Hex 943 = 09 sek 03 Frames
C,D,E - NTSC
4,5,6 - PAL

[kikatu]

Thanks guys, nice brain refreshment on the hexadecimal system. This is useful to fix the display time in modified chapters.