Antialiazed high-resolution frame buffer architecture

• US 6,591,020 B1
• Filed: 12/23/1998
• Issued: 07/08/2003
• Est. Priority Date: 12/23/1998
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Klassen, R. Victor
• Primary Examiner(s): Lee, Thomas D.
• Application Number:
  US09/219,833
• Time in Patent Office: 1,658 Days
• Field of Search: 382/269, 382/254, 382/266, 382/302, 382/305, 382/173, 382/176, 382/178
• US Class Current: 382/269
• CPC Class Codes: G06T 11/001 Texturing; Colouring; Generation of texture or colour inpainting G06T5/77

Abstract

A system processes a color image. A high-resolution cache stores high-resolution data. A low-resolution memory, electrically connected to the high-resolution cache, stores low-resolution data. The low-resolution memory is capable of storing at least as much data as the high-resolution cache. An image processor, connected to both the high-resolution cache and the low-resolution memory, receives sequential segments of low-resolution and antialiased image data. As the image processor receives a current segment of the image data, the image processor either 1) transmits the current segment of image data to the low-resolution memory or 2) transforms the current segment to high-resolution data and transmits the high-resolution data to the high-resolution cache.

Claims

1. A method of generating an antialiased image including at least one object, comprising:

1) receiving current data describing each of the at least one objects into a processing buffer;

2) determining if portions of the current data represent edges;

3) rasterizing portions of the current data representing edges of the at least one objects;

4) receiving the rasterized data into a high resolution cache;

5) transforming the rasterized data in the high resolution cache into low resolution data when;

(i) data in the high resolution cache is valid, and (ii) an image location of data in the high resolution cache is the same as an image location of a current section being processed; and

6) receiving at least one of the current data and the rasterized data into a low resolution memory.

2. The method of generating an image as set forth in claim 1, wherein the step 1 of receiving the current data includes:

7) identifying a current section of a current object to be processed; and

8) determining a current location identifier associated with the current section, the current location identifier identifying a position of the current section within the image.

3. The method of processing an image as set forth in claim 2:

wherein the step 5 includes;

9) determining a first memory location, within the low-resolution memory, as a function of the current location identifier; and

10) receiving the current data into the first memory location of the low-resolution memory;

the method further including;

11) determining a second memory location, within the high-resolution cache, as a function of the current location identifier; and

12) if the previous high-resolution data included in the second memory location corresponds to the same location within the image as the current location identifier, flagging the second memory location as invalid.

4. The method of processing an image as set forth in claim 3, further including:

if the previous high-resolution data stored in the second memory location of the high-resolution cache is flagged as valid;

13) identifying a previous image location associated with the previous high-resolution data stored in the second memory location;

14) determining a low-resolution version of the high-resolution data stored in the second memory location;

15) determining a third memory location, within the low-resolution memory, as a function of the previous image location; and

16) receiving the low-resolution version of the high-resolution data stored in the second memory location of the high-resolution memory into the third memory location of the low-resolution memory;

if the previous high-resolution data stored in the second memory location of the high-resolution cache is flagged as one of valid and invalid;

17)identifying the second memory location as corresponding to the current section;

18) receiving previous low-resolution image data, corresponding to the previous section of the previously processed object at the same location of the current image, from the low-resolution memory into the processing buffer;

19) determining a previous high-resolution representation of the previous low-resolution image data in the processing buffer;

20) merging the high-resolution version of the current low-resolution data with the previous high-resolution representation in the processing buffer;

21) receiving the merged data from the image buffer into the second memory location of the high-resolution cache; and

22) flagging the second memory location of the high-resolution cache as valid.

5. The method of processing an image as set forth in claim 1 further including:

7) after each of the data for each of the objects is processed, outputting the processed data in the high-resolution cache and the low-resolution memory to a color printing device.

6. A method of generating an antialiased image including at least one object, comprising:

1) receiving current data describing each of the at least one objects into a processing buffer;

2) rasterizing portions of the current data representing edges of the at least one objects;

3) receiving the rasterized data into a high resolution cache;

4) transforming the rasterized data in the high resolution cache into low resolution data; and

,

5) receiving at least one of the current data and the rasterized data into a low resolution memory;

wherein if the current section does include at edge, further including;

6) determining if previous high-resolution data is included in the high-resolution cache;

if the previous high-resolution data is included in the high-resolution memory and the previous high-resolution data corresponds to a previous section of a previously processed object, the previous section having a same location within the image as the current section;

7) merging the previous high-resolution data with a high-resolution version of the current data; and

8) receiving the merged data from the step 7 into the high-resolution cache;

if the previous high-resolution data is included in the high-resolution cache and the previous high-resolution data corresponds to a previous section of a previously processed object, the previous section having a different location within the image as the current section;

9) receiving a low-resolution version of the previous high-resolution data from the high-resolution memory into the low-resolution memory;

10) receiving original low-resolution data from the low-resolution memory into the processing buffer, the original low-resolution data corresponding to the same location within the image as the current section;

11) merging a high-resolution version of the original low-resolution data with the high-resolution version of the current data; and

12) receiving the merged data from the step 11 into the high-resolution memory;

if the previous high-resolution data is not included in the high-resolution memory;

13) receiving the high-resolution version of the current data in the high-resolution cache.

7. The method of generating an image as set forth in claim 6, if the current section does not include an edge, the step 5 including:

14) receiving the current data into the low-resolution memory.

8. The method of processing an image as set forth in claim 6, wherein the step 6 of determining if the high-resolution memory includes the previous high-resolution data includes:

14) determining if the second memory location within the high-resolution memory includes the previous high-resolution data

further including;

15) storing the merged data in the second memory location of the high-resolution cache.

9. A method of processing an antialiased image including at least one object, comprising:

1) receiving current data describing each of the at least one objects into a processing buffer;

2) rasterizing portions of the current data representing edges of the at least one objects;

3) receiving the rasterized data into a high resolution cache;

4) transforming the rasterized data in the high resolution cache into low resolution data;

5) receiving at least one of the current data and the rasterized data into a low resolution memory; and

,

6) alpha-blending data previously in the low-resolution memory and that which is received in step 5.

10. A system for processing a color image, comprising:

a high-resolution cache for storing high-resolution data;

a low-resolution memory, connected to the high-resolution cache, for storing low-resolution data, the low-resolution memory being capable of storing at least as much data as the high-resolution cache;

means for determining if portions of a current segment of the image represent an interior or edge portion of the object; and

,

an image processor, connected to both the high-resolution cache and the low-resolution memory, for receiving sequential segments of low-resolution and high resolution image data, as the image processor receives a current segment of the image data, the image processor one of

     1) transmitting the current segment of image data to the low-resolution memory and

     2) transmitting the high-resolution data to the high-resolution cache.

11. The system for processing the color image as set forth in claim 10, wherein the image processor transmits any portion of the current segment of the image data to the low-resolution memory if that portion of the current segment represents the interior of the object, and transmits edge portions of the current segment as high-resolution data to the high-resolution cache.

12. The system for processing the color image as set forth in claim 11, the image processor further including:

means for determining image coordinates of the current segment, the image coordinates identifying a position of the current segment within the image;

means for determining a first location within the low-resolution memory as a function of the image coordinates; and

means for determining a second location within the high-resolution cache as a function of the image coordinates, the image processor one of

     1) transmitting the current segment of image data to the first location within the low-resolution memory and

     2) transmitting the current segment to the second location within the high-resolution cache.

13. The system for processing the color image as set forth in claim 10, further including:

means for outputting the low-resolution data in the low-resolution memory and the high-resolution data in the high-resolution cache to a color output device.

14. A system for processing a color image, comprising:

a high-resolution cache for storing high-resolution data;

a low-resolution memory, connected to the high-resolution cache, for storing low-resolution data, the low-resolution memory being capable of storing at least as much data as the high-resolution cache; and

,

an image processor, connected to both the high-resolution cache and the low-resolution memory, for receiving sequential segments of low-resolution and high resolution image data, as the image processor receives a current segment of the image data, the image processor one of

     1) transmitting the current segment of image data to the low-resolution memory and

     2) transmitting the high-resolution data to the high-resolution cache, wherein the image processor transmits any portion of the current segment of the image data to the low-resolution memory if that portion of the current segment represents the interior of the object, and transmits edge portions of the current segment as high-resolution data to the high-resolution cache, said image processor including;

means for determining image coordinates of the current segment, the image coordinates identifying a position of the current segment within the image;

means for determining a first location within the low-resolution memory as a function of the image coordinates;

means for determining a second location within the high-resolution cache as a function of the image coordinates, the image processor one of

     1) transmitting the current segment of image data to the first location within the low-resolution memory and

     2) transmitting the current segment to the second location within the high-resolution cache; and

,

means for flagging data stored in the second location within the high-resolution cache as one of valid and invalid, if the current segment of the image data is transmitted to the first location within the low-resolution memory, the means for flagging setting the data stored in the second location within the high-resolution cache as invalid.

15. The system for processing the color image as set forth in claim 14, the image processor further including:

means for determining, before new high-resolution data is stored in the second location, if previous data stored in the second location within the high-resolution cache is valid; and

means for transforming valid previous data in the second location within the high-resolution cache to previous low-resolution data and transmitting the previous low-resolution data to the first location within the low-resolution memory.

16. The system for processing the color image as set forth in claim 15, the image processor further including:

means for retrieving previous low-resolution data from the low-resolution memory, the previous low-resolution data corresponding to the image coordinates of the current section;

means for transforming the previous low-resolution data into previous high-resolution data;

means for merging the previous high-resolution data and the current data segment; and

means for transmitting the merged data to the second location within the high-resolution cache and flagging the second location within the high-resolution cache as valid.

17. A system for processing a color image, comprising:

a high-resolution cache for storing high-resolution data;

a low-resolution memory, connected to the high-resolution cache, for storing low-resolution data, the low-resolution memory being capable of storing at least as much data as the high-resolution cache;

an image processor, connected to both the high-resolution cache and the low-resolution memory, for receiving sequential segments of low-resolution and high resolution image data, as the image processor receives a current segment of the image data, the image processor one of

     1) transmitting the current segment of image data to the low-resolution memory and

     2) transmitting the high-resolution data to the high-resolution cache; and

,

means for processing op-codes for instructing a special processor to process the low-resolution data of the current section, the op-codes including a set color command, a set low command, a set low with alpha command, a set high resolution pixel command, a set high resolution rectangle command, and a DMA write operation command.

18. A method of generating an antialiased image including at least two objects, all of a plurality of data for a first one of the objects being processed before any of a plurality of data for a second one of the objects is processed, wherein at least part of the image is stored in a low resolution frame buffer and at least part of the image is stored in a high resolution cache, comprising, for each of the data of each of the objects:

1) receiving data of a current section into a special processor, the current section being a part of a current object being processed;

2) receiving an op-code into the special processor from a general processor, the op-code instructing the special processor for processing the data of the current section; and

3) executing the op-code.

19. The method of processing an image as set forth in claim 18, wherein the op-code is one of a group of instructions including a set color command, a set low command, a set low with alpha command, a set high resolution pixel command, a set high resolution rectangle command, and a DMA write command, the executing step including:

4) if the op-code is the set color command, storing a first operand of the set color command in a first internal register;

5) if the op-code is the set low command, a special processor writing the contents of the first internal register to a low-resolution frame buffer;

6) if the op-code is the set low with alpha command, the special processor determining whether to execute instructions associated with the set low command;

7) if the op-code is the set high resolution pixel command;

8) testing if a high-resolution cache includes data at a target location;

9) if the data is included in the target location, writing the low-resolution data to the target location; and

10) if the data is not included in the target location, identifying neighbors of the target location, reading neighboring data from the low-resolution frame buffer, and scaling-up the low-resolution data and the neighboring data,

11) if the op-code is the set high-resolution rectangle command;

12) testing if a high-resolution cache includes data at a target location;

13) if the data is included in the target location, writing the contents of the first register to the target location;

14) if the data is not included in the target location, identifying neighbors of the target location, reading neighboring data from the low-resolution frame buffer, scaling-up the low-resolution data and the neighboring data; and

15) determining pixels to be set for a high-resolution rectangle; and

16) if the op-code is the DMA write command;

17) copying data from a general processor'"'"'s memory space to the low resolution memory.

20. The method of processing an image as set forth in claim 19, the step 6 including:

18) comparing an operand of the command to all zero'"'"'s;

19) comparing an operand of the command to all one'"'"'s;

20) if the operand includes all zero'"'"'s, determining not to execute instructions associated with the set low command;

21) if the operand includes all one'"'"'s, determining to execute instructions associated with the set low command; and

22) if the operand does not one of include all zero'"'"'s and include all one'"'"'s;

23) reading data from a memory;

24) combining a value in the first internal register, weighted by a contents of a third operand of the command, with the data read from the memory; and

25) writing the combined data to the memory.

21. The method of processing an image as set forth in claim 19, the step 17 including:

18) determining a starting location for a data copy;

19) determining a scanline length to be used during the data copy;

20) determining a number of scanlines to be used during the data copy; and

21) determining a number of bytes to be used between successive scanlines.