公开(公告)号：DE3381217D1

公开(公告)日：1990-03-15

申请号：DE3381217

申请日：1983-07-29

Applicant: IBM

Inventor： LASHER DANA ALFRED ,  STELZENMULLER WILLIAM KARL

IPC: H04N1/409 ,  G06T5/00 ,  G06T5/30 ,  G09G5/28 ,  H04N1/40 ,  H04N1/405

Abstract: The present invention is a method for reducing the visual impact of stepped edges by the selective introduction of gray-scale pels before the image is displayed, in a system capable of receiving and storing non-coded binary image pel values in a direction transverse to the direction of the successive lines. The stored data is modified by assigning gray scale values to a limited number of pels on opposite sides of each identified unit step to create a string of gradually changing gray scale values extending through each identified unit step. Fixed gray scale values are assigned to any pels not previously modified to establish upper and lower limits on gray scale pel values. The displayed image is generated in accordance with the assigned gray scale pel values. The selective introduction of gray scale pels at the identified unit steps has the effect of smoothing the image in the area of the unit steps without blurring the remainder of the character.

公开(公告)号：DE3467965D1

公开(公告)日：1988-01-14

申请号：DE3467965

申请日：1984-02-29

Applicant: IBM

Inventor： LASHER DANA ALFRED ,  STELZENMULLER WILLIAM KARL

IPC: H04N1/409 ,  G06T5/30 ,  H04N1/40 ,  H04N1/411 ,  H04N1/413 ,  H04N7/12 ,  H04N1/41 ,  H04N7/14

Abstract: For use in a teleconference system, a method of reducing line width variations, which are assumed to be the result of undersampling of the original image. Bilevel data received at a remote site is written into a pair of two-dimensional storage arrays. Data stored in the first array is examined row by rowto identify different length-dependent classes of black horizontal pel runs. White or black pels in the second array are overwritten with gray pels at specific pel locations as a function of run length to reduce variations in length. The first array data is then examined on a column by column basis. Black vertical runs are classified and the second array is overwritten with gray pels using the same rules as were applied to horizontal runs. The trilevel second array data may be used to drive a display monitor or may first be subjected to further image processing.