Development of raster scan images from independent cells of imaged data

• US 5,016,190 A
• Filed: 05/05/1988
• Issued: 05/14/1991
• Est. Priority Date: 05/05/1988
• Status: Expired due to Fees

• Current Assignee: Delphax Systems (Xerox Holdings Corp.)
• Original Assignee: Delphax Systems (Xerox Holdings Corp.)
• Inventors: Thomson, Christopher W.
• Primary Examiner(s): Shaw, Dale M.
• Assistant Examiner(s): Zimmerman, Mark K.
• Application Number:
  US07/190,427
• Time in Patent Office: 1,104 Days
• Field of Search: 364/518, 364/519, 364/521, 400/63, 400/76, 400/279
• US Class Current: 345/418
• CPC Class Codes: G06K 15/00 Arrangements for producing a permanent visual presentation of the output data , e.g. computer output printersprinting or plotting combined with another operation, e.g. with conveying, G06K17/00
• CPC Class Codes: G06K 15/02 using printers
• CPC Class Codes: G06K 2215/0077 Raster outputting to the print element(s)
• CPC Class Codes: G09G 5/42 characterised by the display of patterns using a display memory without fixed position correspondence between the display memory contents and the display position on the screen

Abstract

A method and apparatus for converting data representative of a plurality of cells arranged independently of one another on a page into data is raster scan order for subsequent printing. Cell data for individual cells is fetched in an order dependent on the line of raster scan where the cell first occurs and the bit position for the first bit representing the cell. This cell data is compared with earlier fetched cells to build up raster scan lines from cells occuring in the lines.

Claims

1. Apparatus for organizing digital data received from a source such as a host computer into raster scan order, the apparatus comprising:

(a) a cell data memory for storing all data representing attributes of a cell namely,

(i) a number of a starting raster scan in which the cell first occurs,

(ii) a bit location of a first bit in the starting raster scan,

(iii) a number of the raster scan lines in the cell, and

(iv) an address of data representing a portion of the cell in the starting raster scan and commencing at said bit location;

(b) a cell list memory for storing data representing each of said number of raster scan lines for said cell, the data representing the starting raster scan being located at said address;

(c) a new cell register for receiving and storing said cell data prior to the raster scan reaching said starting raster scan;

(d) a current cell register for receiving and temporarily storing said attributes (a)(ii), (a)(iii) and (a)(iv) of said cell;

(e) data comparison means for comparing attributes (a)(ii), (a)(iii) and (a)(iv) of said cell in the new cell register with the corresponding attributes of a previous cell stored in the current cell register, the comparison means including adjustment means for decrementing attributes (a)(iii) and (a)(iv) to the data for the next raster scan line of said cell;

(f) a FIFO for selectively receiving data representing attributes (a)(ii), (a)(iii) and (a)(iv) from either said new cell register or said current cell register;

(g) a line counter actuated after each raster scan to increment to the next raster scan;

(h) line comparison means for comparing the line number from the line counter with attribute (a)(i) to determine whether said data comparison means should be actuated, the line comparison means operating when the raster scan line number matches attribute (a)(i) to determine which of attribute (a)(ii) of the cell in the new cell register and the previous cell in the current cell register takes priority in the raster scan and causing the attributes (a)(ii), (a)(iii) and (a)(iv) of the cell data so selected to pass to the FIFO so that data is received in the FIFO in the order in which the data representing a series of cells is to be added to the raster scan; and

(i) image assembler means for receiving attributes (a)(ii) and (a)(iv) in sequence as attribute (a)(iv) is decremented by the data comparison means, retrieving corresponding data from the cell list memory and assembling the corresponding data into the raster scan.