Appendix 8
3-line VITC for film-to-tape transfer
First line
This line of the code contains Video Tape Time (recorded on the VCR at the time of transfer) in standard IEC form and can also carry Aaton tags or video reel ident (or any arbitrary hexadecimal value) in the binary groups. The CRCC is the IEC standard.
Second line
This line contains KeyKode® information, 3/2 pull-down flags, film manufacturer and film gauge information, and video field ident. The data are carried in the bits that would normally carry both time- and user-data in traditional VITC. The CRCC in this line is the inverse form of the IEC VITC CRCC. The traditional time bits are used to carry the pulldown
Table A8.1 Bit allocation for 3-line VITC 2nd line arranged in bit order.
| VITC bit no. | 3-line VITC content | Traditional VITC content |
| 00-05 | Prefix 4 | Frames units |
| 06-09 | Frames 4 LSB | Binary group 1 |
| 12-15 | Prefix 3 | Frames tens |
| 16-17 | Frame 2 MSB | Binary group 2 LS nibble |
| 18-19 | Max frame count | Binary group 2 MS nibble |
| 22-25 | Prefix 2 | Seconds units |
| 26-29 | Footage 4 (LS digit) | Binary group 3 |
| 32-35 | Prefix 1 (MS digit) | Seconds tens |
| 36-39 | Footage 3 | Binary group 4 |
| 42-5 | Emulsion type (LS digit) | Minutes units |
| 46-49 | Footage 2 | Binary group 5 |
| 52-55 | Emulsion type (MS digit) | Minutes tens |
| 56-59 | Footage 1 (MS digit) | Binary group 6 |
| 62-65 | Film manufacturer + gauge | Hours units |
| 66-69 | Prefix 6 (LS digit) | Binary group 7 |
| 72-74 | Pull-down flags (Table A8.4) | Hours tens (LS bits) |
| 75 | Field flag (Table A8.2) | Hours tens (MS bit) |
| 76-79 | Prefix 5 | Binary group 8 |
flags, film manufacturer and film gauge information, emulsion type and part of the prefix digits of the KeyKode® number. The traditional user bits of the codeword are used to carry the rest of the prefix digits of the KeyKode® number plus the footage count, the maximum frame count and the frame offset from the last KeyKode® number. Tables A8.1 and A8.2 give the details of the contents of the traditional VITC time- and user-bits.
Table A8.2 Bit allocation for 3-line VITC arranged in function order
| VITC bit no. | 3-line VITC content | Traditional VITC content |
| 75 | Field flag (Table A8.2) | Hours tens (MS bit) |
| 72-74 | Pulldown flags (Table A8.4) | Hours tens (LS bits) |
| 62-65 | Film manufacturer + gauge | Hours units |
| 52-55 | Emulsion type (MS Digit) | Minutes tens |
| 42-45 | Emulsion type (LS Digit) | Minutes units |
| 32-35 | Prefix 1 (MS Digit) | Seconds tens |
| 22-25 | Prefix 2 | Seconds units |
| 12-15 | Prefix 3 | Frames tens |
| 00-05 | Prefix 4 | Frames units |
| 76-79 | Prefix 5 | Binary group 8 |
| 66-69 | Prefix 6 (LS digit) | Binary group 7 |
| 56-59 | Footage 1 (MS digit) | Binary group 6 |
| 46-49 | Footage 2 | Binary group 5 |
| 36-39 | Footage 3 | Binary group 4 |
| 26-29 | Footage 4 (LS Digit) | Binary group 3 |
| 18-19 | Max frame count | Binary group 2 MS nibble |
| 16-17 | Frame 2 MSB | Binary group 2 LS nibble |
| 06-09 | Frames 4 LSB | Binary group 1 |
Along with the frame count recorded in the LS byte of the user bits data are two flags which identify the maximum frame count for that key number. The flags are carried in bits 18 and 19 and are interpreted according to information regarding film manufacturer and gauge ident carried in bits 62-65. Table A8.3 gives the details of the max frame count, together with film manufacturer and gauge ident.
The three pulldown flags carried in bits 72-74 identify the video frames that result from the 3/2 pull-down sequence. They do not change in the middle of a frame. To these bits is added a fourth bit (bit 75) to identify the video field. In 25 to 30 transfer with 625/25 systems, pull-down sequences A1 and A2 only are identified. Table A8.4 gives the details.
Table A8.3 Max frame count with film manufacturer and film gauge idents.
| 16 mm | 35 mm | 70 mm | Imax | Ink |
| Bits 18-19 | ||||
| 0 0 reserved | 0 1 16 (4 perf key no/ft & fr) | 0 0 reserved | 0 0 reserved | 0 0 16 (35 mm 4 perf) |
| 0 12 (key no & fr) | 0 1 21 (3 perf head dot, perf 1) | 0 1 16 (5 perf) | 0 1 5 (15 perf head dot) | 0 1 20 (16 mm) |
| 1 0 4 (ft and fr) | 1 0 21 (3 perf centre dot, perf 2) | 1 1 10 (8 perf) | 11 5 (15 perf centre dot) | 1 0 40 (16 mm) |
| 1 1 reserved | 1 1 22 (3 perf tail dot, perf 3) | 0 1 8 (10 perf) | 0 1 5 (15 perf tail dot) | 11 reserved |
| Bits 62-65 (binary values 0-15) | ||||
| 0 = Ink | ||||
| 1 = Agra 35 mm | 2 = Kodak 35 mm | 3 = Fuji 35 mm | 4 = not used | 5 = not used |
| 6 = Agfa 70 mm | 7 = Kodak 70 mm | 8 = Fuji 70 mm | 9 = not used | 10 = not used |
| 11 = Agfa 16 mm | 12 = Kodak 16 mm | 13 = Fuji 16 mm | 14 = not used | 15 = Imax |
The frame number is encoded in binary in the LS byte of the user bits data, along with two flags which identify the maximum frame count for that key number. This MFC is encoded as two bits (18 and 19) and its interpretation is based on the film manufacturer + gauge ID nibble (bits 26-65).
Table A8.4 Pulldown and field ident bit allocation.
As an example of the above, a 35 mm (4 perf) film frame with key number KJ12 3456 7890+12 would be encoded:
| Manufacturer's code | 02 | letter code K for Kodak, encoded as 02 in 35 mm |
| Film type | 96 | letter code J for 5296 emulsion |
| Prefix | 123456 | |
| Footage | 7890 | |
| Frames | &C | hexadecimal representation of 12 frames |
| Field and pulldown | 42 | A frame, field 1, represented in binary form (bits 72-75) |
In 3-line VITC, line 2, this will be encoded as:
