Text quality enhancement via resolution enhancement technique based on separating jaggedness detection and filtering

摘要

A method of separating the detection of text/line jaggedness via a resolution enhancement filter from the actual operation of smoothing image jaggedness or flaws is presented. The advantage of this system is that jaggedness detection can be easily done via established resolution enhancement techniques on a binary signal, but the smoothing can operate on a full color 24 or 32 bit system. This method also performs resolution enhancement or smoothing operations on multi-bit pixel depth data wherein separation is first conducted to detect image jaggedness and, secondly, smoothing operations are performed. In one embodiment of the invention, input data can be comprised of a byte stream connected to a mask FIFO through an ink filter, and to data FIFOs. Pre- filters in this case are connected to additional FIFOs and a resolution enhancement filter to receive a jaggedness detection signal. Processed data is then passed to a buffer where the resolution enhancement filter provides a signal to a halftoner indicating a switch has occurred in the halftone structure of the image. The halftoner processes the data from buffer under control of the resolution enhancement filter and eventually passes the data to the IOT.