Efficient implementation of raster operations flow

• US 20030210410A1
• Filed: 05/13/2002
• Published: 11/13/2003
• Est. Priority Date: 05/13/2002
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Kumar, Santhosh Trichur Natarajan
• Granted Patent: US 7,345,782 B2
• Time in Patent Office: Days
• US Class Current: 358/1.9
• 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 15/1806 Receiving job control commands
• CPC Class Codes: G06K 15/1822 Analysing the received data before processing

Abstract

According to one aspect, a printer supports transparency operations by generating mask data at interpretation stage which indicates whether each bit of a page content would be determined by the result of a raster operation or a prior destination value. The mask data can be used to complete quickly rendering of a page image once the rendering starts. Another aspect enables color fills of objects to be performed efficiently. A raster operations engine may determine whether all the points (pixels) of the object would have the same value if the raster operation is performed. If all pixels would have the same value, the value for only one pixel is computed and used for multiple pixels of the object. According to another aspect, when a pattern is to be tiled on an entire image portion, the pattern data is stored in a memory and provided as an input to rendering operation multiple times.

Claims

1. A method of supporting transparency in a printer, said method comprising:

receiving a plurality of commands specifying a plurality of raster operations, wherein said plurality of raster operations use one or more of a source, a paint and a destination as operands to generate a bit map representing an image portion, said plurality of commands further specifying whether transparency is effective for said source object and said paint, said image portion containing a plurality of points;

generating a data representing whether each of said plurality of points should equal said destination or a result of a corresponding one of said plurality of raster operations; and

generating said bit map based on a result of said plurality of raster operations or said destination according to said data.

2. The method of claim 1, wherein said data comprises a mask data containing a plurality of bits, wherein each of said plurality of bits indicates whether a corresponding one of said plurality of points should equal said destination at a corresponding point or said result.

3. The method of claim 2, wherein one of said plurality of raster operations is not performed if a corresponding one of said plurality of bits in said mask data indicates that the corresponding point in said image portion should equal said destination.

4. The method of claim 2, further comprising:

performing said plurality of raster operations to generate a corresponding plurality of results; and

selecting either one of said plurality of results or a corresponding value in said destination according to said mask data.

5. The method of claim 2, wherein said mask data is generated in an interpreter interpreting said plurality of commands.

6. The method of claim 5, further comprising:

storing in a variable data indicating whether transparency is effective for said source and paint when said bit map is being generated for said image portion.

7. The method of claim 6, wherein said commands are received according to printer control language (PCL).

8. A method of filling color in an image portion of a page to be printed, said method being performed in a printer, said method comprising:

receiving a plurality of commands specifying content for a portion of said page, said portion containing a plurality of points, said plurality of commands specifying a raster operation to be performed to generate a bit map representing said portion, said raster operation being performed on at least one operand, wherein said plurality of commands indicate that said one operand is to be filled with a color;

determining whether performing said raster operation would result in a same value being generated for all of said plurality of points; and

if said same value would be generated, performing said raster operation for one of said plurality points to determine said same value and using said same value for all of said plurality of points.

9. The method of claim 8, wherein said raster operation comprises an inversion.

10. The method of claim 9, wherein said one operand comprises a source or a paint.

11. The method of claim 10, wherein said determining is performed in a raster operation module.

12. A method of tiling patterns on a page to be printed in a printer, said method comprising:

receiving a plurality of commands specifying a pattern to be tiled on an entire image portion, said pattern being defined by a pattern data;

storing said pattern data in a memory; and

providing said pattern data stored in said memory a plurality of times as an input to raster operations to cause said pattern to be tiled multiple times on said entire image portion.

13. The method of claim 12, wherein said providing provides said pattern data all the times when tiling on said entire image portion.

14. The method of claim 13, wherein said data stored in said memory is viewed as a circular buffer.

15. A printer supporting transparency, said printer comprising:

means for receiving a plurality of commands specifying a plurality of raster operations, wherein said plurality of raster operations use one or more of a source, a paint and a destination as operands to generate a bit map representing an image portion, said plurality of commands further specifying whether transparency is effective for said source object and said paint, said image portion containing a plurality of points;

means for generating a data representing whether each of said plurality of points should equal said destination or a result of a corresponding one of said plurality of raster operations; and

means for generating said bit map based on a result of said plurality of raster operations or said destination according to said data.

16. The printer of claim 15, wherein said data comprises a mask data containing a plurality of bits, wherein each of said plurality of bits indicates whether a corresponding one of said plurality of points should equal said destination at a corresponding point or said result.

17. The printer of claim 16, wherein one of said plurality of raster operations is not performed if a corresponding one of said plurality of bits in said mask data indicates that the corresponding point in said image portion should equal said destination.

18. The printer of claim 16, further comprising:

means for performing said plurality of raster operations to generate a corresponding plurality of results; and

means for selecting either one of said plurality of results or a corresponding value in said destination according to said mask data.

19. The printer of claim 16, wherein said mask data is generated in an interpreter interpreting said plurality of commands.

20. The printer of claim 19, further comprising:

means for storing in a variable data indicating whether transparency is effective for said source and paint when said bit map is being generated for said image portion.

21. The printer of claim 20, wherein said commands are received according to printer control language (PCL).

22. A printer controller filling color in an image portion of a page to be printed, said printer controller comprising:

means for receiving a plurality of commands specifying content for a portion of said page, said portion containing a plurality of points, said plurality of commands specifying a raster operation to be performed to generate a bit map representing said portion, said raster operation being performed on at least one operand, wherein said plurality of commands indicate that said one operand is to be filled with a color;

means for determining whether performing said raster operation would result in a same value being generated for all of said plurality of points; and

means for performing said raster operation for one of said plurality points to determine said same value and using said same value for all of said plurality of points, if said same value would be generated.

23. The printer controller of claim 22, wherein said raster operation comprises an inversion.

24. The printer controller of claim 23, wherein said one operand comprises a source or a paint.

25. The printer controller of claim 24, wherein said means for determining is comprised in a raster operation module.

26. A printer tiling patterns on a page to be printed, said printer comprising:

means for receiving a plurality of commands specifying a pattern to be tiled on an entire image portion, said pattern being defined by a pattern data;

means for storing said pattern data in a memory; and

means for providing said pattern data stored in said memory a plurality of times as an input to raster operations to cause said pattern to be tiled multiple times on said entire image portion.

27. The printer of claim 26, wherein said means for providing provides said pattern data all the times when tiling on said entire image portion.

28. The printer of claim 27, wherein said data stored in said memory is viewed as a circular buffer.

29. A computer readable medium carrying one or more sequences of instructions for causing a printer to support transparency, wherein execution of said one or more sequences of instructions by one or more processors contained in said printer causes said one or more processors to perform the actions of:

receiving a plurality of commands specifying a plurality of raster operations, wherein said plurality of raster operations use one or more of a source, a paint and a destination as operands to generate a bit map representing an image portion, said plurality of commands further specifying whether transparency is effective for said source object and said paint, said image portion containing a plurality of points;

generating a data representing whether each of said plurality of points should equal said destination or a result of a corresponding one of said plurality of raster operations; and

generating said bit map based on a result of said plurality of raster operations or said destination according to said data.

30. The computer readable medium claim 29, wherein said data comprises a mask data containing a plurality of bits, wherein each of said plurality of bits indicates whether a corresponding one of said plurality of points should equal said destination at a corresponding point or said result.

31. The computer readable medium claim 30, wherein one of said plurality of raster operations is not performed if a corresponding one of said plurality of bits in said mask data indicates that the corresponding point in said image portion should equal said destination.

32. The computer readable medium claim 30, further comprising:

performing said plurality of raster operations to generate a corresponding plurality of results; and

selecting either one of said plurality of results or a corresponding value in said destination according to said mask data.

33. The computer readable medium of claim 30, wherein said mask data is generated in an interpreter interpreting said plurality of commands.

34. The computer readable medium of claim 33, further comprising:

storing in a variable data indicating whether transparency is effective for said source and paint when said bit map is being generated for said image portion.

35. The computer readable medium of claim 34, wherein said commands are received according to printer control language (PCL).

36. A computer readable medium carrying one or more sequences of instructions for causing a printer to fill color in an image portion of a page to be printed, wherein execution of said one or more sequences of instructions by one or more processors contained in said printer causes said one or more processors to perform the actions of:

receiving a plurality of commands specifying content for a portion of said page, said portion containing a plurality of points, said plurality of commands specifying a raster operation to be performed to generate a bit map representing said portion, said raster operation being performed on at least one operand, wherein said plurality of commands indicate that said one operand is to be filled with a color;

determining whether performing said raster operation would result in a same value being generated for all of said plurality of points; and

if said same value would be generated, performing said raster operation for one of said plurality points to determine said same value and using said same value for all of said plurality of points.

37. The computer readable medium of claim 36, wherein said raster operation comprises an inversion.

38. The computer readable medium of claim 37, wherein said one operand comprises a source or a paint.

39. The computer readable medium of claim 38, wherein said determining is performed in a raster operation module.

40. A computer readable medium carrying one or more sequences of instructions for causing a printer to tile patterns on a page, wherein execution of said one or more sequences of instructions by one or more processors contained in said printer causes said one or more processors to perform the actions of:

receiving a plurality of commands specifying a pattern to be tiled on an entire image portion, said pattern being defined by a pattern data;

storing said pattern data in a memory; and

providing said pattern data stored in said memory a plurality of times as an input to raster operations to cause said pattern to be tiled multiple times on said entire image portion.

41. The computer readable medium of claim 40, wherein said providing provides said pattern data all the times when tiling on said entire image portion.

42. The computer readable medium of claim 41, wherein said data stored in said memory is viewed as a circular buffer.