Abstract: A printer driver, for example a QuickDraw printer driver, keeps track of changes in a drawing environment (specified by a GrafPort) by saving State records. Rather than filling up the State with the contents of each pattern and clip region, references to each of these members are stored in the State. This referencing allows each component of a State to be saved separately while still allowing the State to be reproduced precisely when it is time to draw. Referencing can greatly reduce disk accesses and file size, thereby accelerating printing. Referencing also allows significant time to be saved during state comparison. Whereas previous drivers have required a State to GrafPort comparison at translation (drawing) time, in the present method, each reference in the current state may be compared with references from the previous state to see which fields have changed. Comparing references, which may be stored in four bytes, is much faster than comparing large patterns and regions.

Abstract: A color printing system with reduced bleed includes a computer and a color printer. The computer has a digital processor and memory accessed by the digital processor, where the memory stores printable objects selected from the group comprising graphic objects and non-graphic objects and pixel maps corresponding to the graphic objects and the non-graphic objects. The color printer is coupled to the computer and is capable of printing the pixel maps using color pixels and black pixels. An image processor implemented on the computer identifies the graphic objects among the printable objects, adjusts pixel densities of the graphic objects, and renders the printable objects as the pixel maps, such that black pixel densities of pixel maps of the graphic objects are reduced without reducing black pixel densities of pixel maps of the non-graphic objects.

Abstract: A method for object based color matching when printing color documents. Objects are anything that can be drawn, and include text, rectangle, oval, region, polygon, and PixMaps. Color matching is performed on each object in a page prior to rendering the object into a pixel map. This is accomplished by setting up multiple concurrent color matching sessions that have different rendering intents. Depending upon the object type, a color matching session with a particular rendering intent is used to perform color matching on the object.

Abstract: A method and apparatus for rendering using band by band depth adjustment preferably begins by recording extents for each object on a page. An extent indicates where color or non-color ink begins and ends on a page. Extent blocks are then created. An extent block is comprised of at least one extent of the same ink type. Next, a band is created for each extent block. The bit depth for each band is adjusted based upon the ink type associated with each extent block. If the ink is black or white, a band having a bit depth of one is created. If the ink is color or gray scale, the bit depth is adjusted to the proper depth for that band. An object or portion of an object is then rendered into a band having the necessary bit depth for that object.