公开(公告)号：DE3751390D1

公开(公告)日：1995-08-10

申请号：DE3751390

申请日：1987-03-10

Applicant: IBM

Inventor： PENNEBAKER WILLIAM B ,  MITCHELL JOAN L ,  MINTZER FREDERICK C

IPC: H04N1/00 ,  G06T3/40 ,  G09G3/00 ,  G09G3/20 ,  G09G5/34 ,  G09G5/36 ,  G09G5/39 ,  G09G5/395 ,  H04N1/387 ,  H04N1/40 ,  G06T1/60

公开(公告)号：CA1241606A

公开(公告)日：1988-09-06

申请号：CA502706

申请日：1986-02-25

Applicant: IBM

Inventor： CHEN YI-HSIN ,  MINTZER FREDERICK C ,  PENNINGTON KEITH S

IPC: H04N1/387 ,  G06T1/00 ,  G06T5/00 ,  H04N1/40 ,  H04N1/403 ,  H04N1/405 ,  H04N1/23

Abstract: SYSTEM FOR REPRODUCING MIXED IMAGES An electronic processing system for reproducing mixed images, i.e., original images having areas of continuous tone and areas of text, in such a manner that both areas are of balanced, good quality in the reproduction. The image to be reproduced is (1) divided into non-overlapping 4 x 4 blocks of pixels or picture elements, and, (2) each block is classified as either of TEXT or IMAGE, based on the values of the 16 pixels within it. The classification is improved by (3) eliminating short runs of blocks with the same classification. The pixel values are then adjusted by appropriately (4) thresholding those in the TEXT blocks, and, (5) averaging those in the image blocks. The IMAGE block values are quantized to one of 17 levels using an improved error diffusing process and then mapped onto a 4 x 4 pattern preparatory to (6) merging the binary images for the TEXT and IMAGE areas. Converting to various patterns to suit the output device such as a specific printer is possible by permitting the conversion of the bits for an IMAGE block from one pattern table to another.

公开(公告)号：CA1225479A

公开(公告)日：1987-08-11

申请号：CA469463

申请日：1984-12-06

Applicant: IBM

Inventor： MITCHELL JOAN L ,  ANDERSON KAREN L ,  MINTZER FREDERICK C

IPC: G06F12/02 ,  G06F12/04 ,  G06T3/60 ,  G06F15/62

Abstract: A method for rotation of a binary image by 180 degrees, includes the steps of: positioning first and second address pointers at the center or at the beginning and end respectively of an image to be rotated; indexing the first pointer in a first direction through said image; indexing the second pointer in a second direction through said image; exchanging, for each index step, a first image word at the first pointer with a second image word, at the second pointer if the first image word and the second image word have any two bits with different values; reversing all exchanged words; storing the reversed, exchanged words at said pointer locations; repeating the above steps until the first pointer and the second pointer have been indexed through all words in the image at which point the image has been rotated by 180 degrees.

公开(公告)号：CA1220581A

公开(公告)日：1987-04-14

申请号：CA467900

申请日：1984-11-15

Applicant: IBM

Inventor： MINTZER FREDERICK C ,  ANDERSON KAREN L ,  MITCHELL JOAN L

IPC: H04N1/393 ,  G06T3/40 ,  G09G5/26 ,  G09G5/393 ,  G09G3/00

Abstract: A method for expanding a binary image includes the steps of: storing the image in bit sequence; inserting for each string of 5 bits along a first axis one or more expansion bits, to convert each said string of ; bits to a string of 6 bits; assigning a value to each expansion bit generated by the above step; inserting one or more rows of expansion bits for each 5 rows of bits along a second axis of the image to convert each 5 rows of bits to 6 rows of bits along the second axis of the image; assigning a value to each expansion bit generated by the above steps; storing the enlarged image generated by the above steps. YO983-092