A mapping-type data signal optimizer performs a code-point sorting function to optimize downloading of programmed symbols. A present-state list of values of programmed symbols already downloaded to a peripheral device is sorted, and a similar intended-state list of programmed symbols intended to be downloaded is likewise sorted. A search is performed to detect any commonalities that might exist between the present-state and intended-state programmed-symbol values, even under differing programmed-symbol designators. When such a commonality is detected, the intended- state designator is altered to be equal to the present-state designator; thus, that particular programmed symbol value need not be redownloaded.
A system for compressing an image. The system determines a set of commonly occurring color values in the image and associates a designator with each commonly occurring color value. For each pixel in the image, the system identifies a color value for the pixel. If the pixel has a commonly occurring color value, the system substitutes the associated designator for the commonly occurring color value. Otherwise, if the pixel does not have a commonly occurring color value, the system adds the color value to a rare color list, and substitutes a special designator for the color value to indicate that the color value for the pixel is contained in the rare color list.
Under VTAM, or similar-type data communications system, co-executing "partner" processes typically exchange data via SEND and RECEIVE requests that are processed by VTAM. A method in accordance with the invention provides a way for optimizing this data exchange process. The optimized method bypasses VTAM to provide significant savings of system resources and improved execution speed over that required for VTAM to process the same SEND and RECEIVE requests.
An optimizer system optomizes and validates data streams in whcih double-byte character set data may be transmitted. The optimizer, maintaining an image or map of data contained in a peripheral device buffer, sets and monitors the status of three flags located in extended attribute planes for the purpose of processing data stream orders when a double-byte character set is in use.
In a VTAM- or similar-type data communications system, a succession of terminal screen displays are compared over time to determine whether any common display portions can be used as "local formats." If so, local formats are defined and downloaded to the terminal controller and periodically updated if needed.
A list data sorting control method carried out by a data processing apparatus. Blocks are generated for demarcating or dividing meaningfully list data displayed on a display device. The list data located within the block are handled as movable units to be moved for rearranging the list data. When a plurality of the blocks bear inclusion relation to one another, rearrangement of the list data is performed in accordance with the inclusion relation.
