Partially pre-rasterizing image data

1. A method for printing a page with a printing device comprising:

receiving a page description in the printing device;

converting the page description into a display list;

sectioning the display list into image strips;

determining if each of the image strips can be rasterized within a predetermined amount of time; and

if an image strip cannot be rasterized within the predetermined amount of time, estimating a minimum amount of the image strip to be pre-rasterized to avoid print overrun and pre-rasterizing said minimum amount of the image strip.

2. The method of claim 1 , wherein sectioning the display list into strips comprises:

sorting display commands of the display list by vertical location on a page;

and allocating the sorted display commands Into groups of display commands corresponding to horizontal image strips of the page.

3. The method of claim 1 , wherein determining if the image strips can be rasterized within the predetermined amount of time comprises:

calculating a rasterization execution time (RET) for the image strip;

calculating a rasterization time available (RTA) for the image strip; and

comparing the RET of the image strip to the RTA of the image strip.

4. The method of claim 3 , wherein a surplus processing time fi-om an RET for a previous image strip is added to the RTA for the image strip.

5. The method of claim 3 , wherein estimating an amount of the image strip to be pre-rasterized to avoid print-overun comprises:

subtracting the RTA of the image strip from the RET of the image strip; and

converting a difference between the RTA and RET into a corresponding quantity of display list commands in the image strip.

6. The method of claim 1 , further comprising printing the page including:

rasterizing a remainder of the image strip during use by a print engine of rasterized data for a previous image strip; and

sending rasterized data for the image strip to the print engine.

7. The method of claim 6 , wherein rasterizing a remainder of the image strip and sending rasterized data for the image strip to the print engine are performed on each image strip of the display list in sequence.

8. A machine-readable medium comprising instructions that, when executed by a processor of a printing device, cause the processor to:

receive a page description in the printing device;

convert the page description into a display list;

section the display list into image strips;

determine if each of the image strips can be rasterized within a predetermined amount of time; and

if an image strip cannot be rasterized within the predetermined amount of time, estimate a minimum amount of the image strip to be pre-rasterized to avoid print overrun and pre-rasterizing said minimum amount of the image strip.

9. The medium of claim 8 , wherein the instructions, when executed, further cause the processor to section the display list into strips by:

sorting display commands of the display list by vertical location on a page;

and allocating the sorted display commands into groups of display commands corresponding to horizontal image strips of the page.

10. The medium of claim 8 , wherein the instructions, when executed, further cause the processor to determine if the image strips can be rasterized within the predetermined amount of time by:

calculating a rasterization execution time (RET) for the image strip;

calculating a rasterization time available (RTA) for the image strip; and

comparing the RET of the image strip to the RTA of the image strip.

11. The medium of claim 10 , wherein the instructions, when executed, further cause the processor to add a surplus processing time from an RET for a previous image strip to the RTA for the image strip.

12. The medium of claim 10 , wherein the instructions, when executed, further cause the processor to:

subtract the RTA of the image strip from the RET of the image strip; and

convert a difference between the RTA and RET into a corresponding quantity of display list commands in the image strip.

13. The medium of claim 8 , wherein the instructions, when executed, further cause the processor to:

rasterize a remainder of the image strip during use by a print engine of rasterized data for a previous image strip; and

send rasterized data for the image strip to the print engine.