Line Conditioned Data Stream
Line Conditioned Data Stream (LCDS) refers to the Xerox print stream that originated as EBCDIC impact printer data that includes embedded printer controls to define the fonts, graphics, and data layout for the printed output. Impact printer data includes simple carriage and forms control commands such as "skip to top of page", skip to a pre-defined channel on a page, over-print and a basic carriage return, line feed commands. The purpose of these commands was to mimic the action of a typewriter. LCDS built upon the impact data stream by embedding commands to take advantage of the image processing capabilities of the Xerox printers.
LCDS requires a significantly lower bandwidth, as the individual elements of the documents are not assembled until they reach the printer where the resources are saved. Complex elements, such as forms, do not need to be repeatedly re-sent as part of the data stream from the host to the printer. The system has to send only the truly variable data to the printer. The consequence: lower data transfer.
LCDS and Metacode – Similarities and Differences
LCDS is closely related to metacode, another format developed by Xerox. In contrast to LCDS, metacode is fully formatted, i.e., data such as the text position and orientation, font, overlay, images and highlight color are predefined through corresponding commands. In contrast, LCDS files do not contain any information about the position, formatting, etc. and need to be defined using JSL (Job Source Library) configuration files and DJDE (dynamic job descriptor entry) commands.
However, LCDS and metacode do use the same resources: fonts, color (black, white, highlight color), logos, graphics and images.
Important: In practice, both formats are used in the same file. To process such files, a filter is required that can recognize, process, and convert both LCDS and metacode. Compart provides just such a solution in the form of the LCDS filter (see "Technological support" section).
Compart’s LCDS filter is able to recognize and process both LCDS and metacode data. If an LCDS file also contains metacode, it will automatically change to the respective processing mode.
And: The LCDS filter supports the "Change overlay” function within multiple copies.
Compart’s MFF filters (mixed format filter) are the basis of the MFF architecture for DocBridge products. Some MFF filters read files in different formats (input filters) while others are used to write files in the respective output format (output filters). In many cases, a format is supported for both input and output.
The strength of the Compart MFF architecture is its ability to quickly and effectively convert documents in various formats into others, or integrate them into a document using a specific format. For example, documents in AFP, SAPGOF or PCL can be converted to PDF and can also be merged into a single PDF document.
When converting one format into another, Compart uses the shared object format, the so-called presentation area (PA), which is able to represent the visual data and metadata of all supported formats. An MFF input filter converts an input file into the PA format in main memory and an MFF output filter then converts the PA format saved in main memory into an output file.
LCDS Conversion Directions
A complete overview of all supported input and output formats is provided in the Compart Matrix. Compart software solutions enables highly complex, single pass operations with flexibility and reliability for high availability, high volume environments.