ISO 1007:2000 pdf download

ISO 1007:2000 pdf download.Photography — 135-size film andmagazine-Specifications.
7 Latent-image digital bar-codes
7.1 General
Latent-image bar-codes shall conform to the locations and dimensions shown in Figure 1 and given in Table 1.
A 23-bit dual-track latent-image bar-code, which identifies the manufacturer/film type using a system of DX numbers (see normative annex A), shall be located on the edge nearest the C datum plane adjacent to each full- frame and half-frame number on films designed for colour-negative processing. The bar-codes are visible only after the film has been processed. When processed film is used with an appropriate film-code reader and an automatic printer, colour printing can be optimized for each specific film so identified.
Frame-number identification may also be incorporated in different ways. One method is to expand the basic 23-bit dual-track latent-image code by adding eight more bits for frame-number identification. Another method would be to utilize a 13-bit single-track, modified 3-of-9, latent-image bar-code on the opposite film edge.
Use of latent-image bar-codes on 135-size films, other than those intended for colour negative processing, is optional.
7.2 Dual-track latent-image bar-code
Each dual-track latent-image bar-code consists of adjacent data and clock tracks, each with the same number of elements (23 without and 31 with encoded frame numbers). Each bar-element represents a digital binary bit, with exposed elements (bars) representing a 1 bit and unexposed elements (spaces) representing a 0 (zero) bit, except in the entry pattern (see 7.2.1.1).
7.2.1 Definition of the data track
The first reason for encoding information into the data track is to provide a unique DX number identification (see normative annex A for information regarding the assignment of DX numbers). The DX number has two parts (part 1 and part 2). The two parts are used in combination to identify products. Part 2 shall not be encoded without part 1. Part 1 is described in 7.2.1.2, and part 2 is described in 7.2.1.4.
The second reason for encoding information into the data track is to encode the frame numbers.
7.2.1.1 Entry pattern
The 6-bit entry pattern is used by the bar-code reader to detect the beginning of a code sequence. The final bit of
the entry pattern shall always be an unexposed element (space).
7.2.1.2 Identification array for part 1 of the DX number
The part 1 DX code has 7 bits. The 7-bit stream, starting with bit 7 and ending with bit 13, is used for encoding the part 1 DX number assigned to a product in accordance with the procedure specified in annex A.
The sequences of exposed and unexposed positions that identify the 128 available part 1 DX numbers are given in Table 3. (They are arranged in an ascending binary sequence for ease of referencing.) Dashes (—) in one of the seven element position columns of Table 3 signify an unexposed element (space); a number signifies an exposed element (bar). For example, the part 1 DX number 41 is encoded by the combination of unexposed elements (spaces) in positions 7, 9, 11, and 12, and exposed elements (bars) in positions 8, 10, and 13.
Sensitizers may use a single part 1 DX number to identify a number of films that are designed for the same chemical process.
7.2.1.3 Unassigned bit
The unassigned bit is in bit position 14 and shall be an unexposed element (space).
7.2.1.4 Identification array for part 2 of the DX number
The identification for part 2 of the DX number is 4 bits, starting with bit 15 and ending with bit 18. This 4-bit array shall encode the specific part 2 DX number (specified in Table 4) that has been assigned to that product under the procedure specified in annex A. Any individual location assigned as part of the part 2 DX number shall represent an exposed element (bar). Dashes (—) in Table 4 represent an unexposed element (space).
The 16 possible combinations of this array are encoded as a 4-bit binary number, with bar position number 15 representing the most significant bit, and bar position number 18 representing the least significant bit.
7.2.1.5 Identification array for frame numbers
This optional 7-bit array may be added to encode whole and half-frame numbers in accordance with the patterns given in Table 5. Bar positions 19 to 25 are a 7-bit binary representation of the frame number, with position number 19 representing the most significant bit and position number 25 representing the least significant bit. Frame numbers prior to the zero frame are derived by successive binary subtraction.
Bar position number 25 is exposed in those array’s that encode half-frame numbers. This is the half-frame “flag”. Although the longest 135-size standard film length is 36 exposures, Table 5 provides the logical encodement for
frame numbers greater than 36A in case these numbers should be needed in the future.
7.2.1.6 Second unassigned bit
A second unassigned bit shall be included in bit position 26 only if the optional frame-number array is included. The second unassigned bit shall be an unexposed element (space).
7.2.1.7 Parity bit
A parity bit shall be provided in bit position 19 in order to create even parity with data bits 7 through 18 inclusive. (The total number of exposed elements [bars] in data positions 7 through 18, plus the parity bit position, shall be an even number.)
Under the optional dual-track frame-numbering system, the parity bit is used to create even parity with data bits 7 through 25 inclusive and is located in bit position 27.
The unassigned bits are part of this consideration, but since they are always spaces they have no affect on the count of bars for parity.
7.2.1.8 Exit pattern
The exit pattern shall be 4 bits as shown in Figure 1. It is used by a bar-code reader to detect the end of a code sequence.