VARIABLE LENGTH CODING METHOD AND APPARATUS

• US 3,643,019 A
• Filed: 04/22/1970
• Issued: 02/15/1972
• Est. Priority Date: 04/22/1970
• Status: Expired due to Term

• Current Assignee: John Prickett Beltz
• Original Assignee: John Prickett Beltz
• Inventors: Beltz, John Prickett
• Primary Examiner(s): Richardson, Robert L.
• Application Number:
  US05/030,812
• Time in Patent Office: 664 Days
• Field of Search: 178/DIG.3,DIG.34,7.7,6,6.8
• US Class Current: 358/426.12
• CPC Class Codes: B41B 19/01 having electron-beam tubes producing an image of at least one character which is photographed
• CPC Class Codes: B41B 27/28 Control, indicating, or safety devices for individual operations or machine elements in devices for supplying molten metal B41B11/86, B41B11/88; for light sources B41B21/08
• CPC Class Codes: G09G 1/14 the beam tracing a pattern independent of the information to be displayed, this latter determining the parts of the pattern rendered respectively visible and invisible

Abstract

There is disclosed a method and apparatus for providing a coded representation of a black and white graphical pattern, such as an alphanumeric character or other symbol, a line drawing, etc., which reduces the storage space needed to store a representation of the pattern. Each pattern is divided into a plurality of adjacent linear zones that include one or more zonal segments of alternating black and white colors. A zonal segment is represented by a combination of groups of binary numbers, with each group containing a predetermined number of individual binary bits. The number of groups in the combination varies depending on the length of the segment. Successive combinations are distinguished from each other by reserving a first position in each group as a delimiter bit position to denote the beginning of each combination. A second predetermined position in the first combination of a zone is designated as a color bit position and specifies the visual reflectance of the first zonal segment of the zone. Succeeding zonal segments in a zone alternate in color. The color bit position in the combination defining the last segment of a zone is redesignated as an end-of-zone bit position to denote the end of a zone. Thus the combinations defining a zone vary depending on the length of the zone, and the number of groups in a combination varies depending on the length of the corresponding zonal segment.

Claims

1. In a system providing a coded representation of a pattern, which pattern is divisible into a plurality of substantially linear adjacent zones each including one or more zonal segments, with successive ones of said segments in a zone alternating in exhibiting different visual reflectance states, the combination comprising:

means for scanning said pattern by a plurality of substantially linear adjacent scanlines, each corresponding to a different one of said zones, to produce signals denoting the content of said pattern;

logic means responsive to said signals for generating a plurality of combinations of groups of coded signals for defining said pattern, with each single combination representing a single zonal segment;

each of said groups including a predetermined number of individual binary signals with the number of groups in each combination selected to correspond to the length of its associated zonal segment; and

logic means responsive to said signals for generating a delimiter binary signal of one value at a predetermined position in the first group of a combination with the same predetermined position in every remaining group of said combination selected to exhibit a binary signal of a second value whereby one combination is distinguished from the next successive combination to separate successive segments in a zone.

2. The combination in accordance with claim 1 that further includes:

means for selecting as a color designator a second predetermined position in the first group of a combination representing the first segment in a zone to denote that said first segment exhibits one visual reflectance state when a binary signal of one value is recorded in said second predetermined position and exhibits another visual reflectance state when a binary signal of the other Value is recorded therein.

3. The combination in accordance with claim 2 that further includes:

means for redesignating said second predetermined position in said first group of the combination representing the last segment in a zone as a zonal end position to denote the last segment in a zone when a binary signal of one value is recorded therein so that one zone can be distinguished from another when the number of zonal segments vary from zone to zone.

4. The combination in accordance with claim 3 that further includes:

means for utilizing said second predetermined position as a data position to record therein a data signal in groups other than the first group in said combinations.

5. In a system for providing a coded representation of a pattern having an outline trace of one visual reflectance state and a background of a different visual reflectance state, the combination comprising:

means for overscanning said pattern by a plurality of successive scanlines which divide said pattern into a plurality of zones, each zone of said pattern having one or more zonal segments corresponding to said outline trace and said background;

means responsive to said overscanning for producing outline trace image signals and background signals for the several zones;

means for digitizing said outline trace image signals and said background signals to provide a plurality of outline trace pulses and background pulses;

means for alternately counting by groups said outline trace pulses and said background pulses to provide combinations of groups of numbers defining said outline trace zonal segments and said background zonal segments, with the number of groups in each of said combinations depending on the length of its corresponding zonal segment; and

means for suppressing combinations defining background zonal segments that occur outside of the bounds of the outline trace of said pattern so as to compact the data representing said pattern.

6. The combination in accordance with claim 5 wherein said means for counting include a pair of binary counters for counting said outline trace pulses and said background pulses.

7. The combination in accordance with claim 6 wherein each one of said groups includes a predetermined number of binary signals.

8. The combination in accordance with claim 7 that further includes;

means for providing a delimiting binary signal of one value in a predetermined position in the first group in each combination and a binary signal of a second value in the same predetermined position of every other group in said combination to distinguish between successive combinations to separate different zonal segments in a zone.

9. The combination in accordance with claim 8 that further includes:

means for providing a color designator binary signal in a second predetermined position in said first group of the first combination in a zone to denote a zonal segment of one visual reflectance state when a binary signal of one value is recorded therein and a zonal segment of the other reflectance state when a binary signal of another value is recorded therein.

10. The combination in accordance with claim 9 that further includes:

means for providing a zone end determining signal in said second predetermined position in combinations other than the first combination of a zone to denote the last zonal segment in a zone when a binary signal of one value is recorded therein.

11. The method of providing a coded representation of a pattern having an outline trace of one visual reflectance state and a background of a different visual reflectance state, comprising the steps of:

overscanning said pattern by a plurality of successive scanlines to derive outline trace image signals and background signals, said scanlines dividing said pattern into a plurality of zones each including one or more zonal segments corresponding to said outline trace and said background;

digitizing said outline trace image signals and said background signals to provide a plurality of outline trace pulses and background pulses;

alternately counting by groups said outline trace pulses and said background pulses to provide combinations of equal length groups of numbers defining said outline trace zonal segments and said background zonal segments, with the number of groups in each of said combinations depending on the length of its corresponding zonal segment; and

suppressing combinations defining background zonal segments that occur outside of the bounds of the outline trace of said pattern so as to compact the data representing said pattern.

12. In a system for presenting to a display means a pattern that is divisible into a plurality of substantially linear adjacent zones each of which includes one or more zonal segments, with successive ones of said segments in a zone exhibiting different visual reflectance properties, the combination comprising:

a display means for scanning in a sequential zonal manner;

storage means storing a coded representation of a pattern as a plurality of combinations of groups of coded bits, each of said combinations corresponding to a separate zonal segment and each of said groups containing a like number of individual binary bits, the number of groups in a combination varying as a function of the length of its corresponding zonal segment; and

means for reading out the contents of said storage means to said display means selectively.

13. The combination as claimed in claim 12 wherein the storage means stores a framing binary bit of one value at a first predetermined position in the first group of a combination and a binary bit of second value at the corresponding predetermined position in every remaining group of the same said combination, whereby any combination is distinguishable from the next successive combination for the same zone.

14. The combination as claimed in claim 13, wherein said storage means stores an end of zone bit of one binary value at a second predetermined position in the first group of the last combination of a zone so that the stored information for one zone is distinguishable from that of the next zone when the combinations of groups of coded bits therefor are in sequence.