公开(公告)号：JPH0285974A

公开(公告)日：1990-03-27

申请号：JP23629188

申请日：1988-09-22

Applicant: IBM JAPAN

Inventor： SEKIYA KAZUO ,  SHIRAISHI YUICHI

IPC: H04N1/40 ,  G06T5/00 ,  G09G5/00 ,  G09G5/391 ,  H04N1/41

Abstract: PURPOSE:To accelerate operating speed and to reduce a cost by dividing a first halftone signal of N bits into high-order M bits and low-order (N-M) bits, generating a second halftone signal by adding the correction value of a selected table on the M bits, and supplying it to a display device of halftone of 24M level. CONSTITUTION:(P X Q) second halftone signals are generated by dividing the first halftone signal of N bits into the high-order M bits and the low-order (N-M) bits, selecting one of 2N M tables having (P X Q) correction values which satisfy P X Q>=2N M, respectively by using (N-M) bits, and adding the correction value of the selected table on the M bits. The number of dots of a display device 13 which displays the halftone of 2N level is less than that of display dots of a display device 11 which displays the halftone of 2M level. Also, it is assumed that N represents an integer >=2, and M is the integer which satisfies N>M>=1, and P and Q are natural numbers, and represent the number of dots in horizontal and vertical directions, respectively. In such a manner the operating speed can be accelerated, and the cost is reduced.

公开(公告)号：DE68918911T2

公开(公告)日：1995-04-20

申请号：DE68918911

申请日：1989-08-08

Applicant: IBM

Inventor： SEKIYA KAZUO SUNHEIM ASAMI ,  SHIRAISHI YUICHI

IPC: H04N1/40 ,  G09G5/00 ,  G09G5/10 ,  H04N1/407

Abstract: A method for use in a digital data display system for converting selected M gray levels in a K-gray scale to an N-gray scale (where K>N>/=M) comprising: a stage of creating a first table in which each of said M gray levels is mapped, in accordance with the order and magnitude of the relative brightness in the K-gray scale, in different M gray levels in the N-gray scale, and a stage of creating a second table in which the M gray levels in the N-gray scale mapped in said first table is mapped correspondingly to the M gray levels in said K-gray scale.

公开(公告)号：DE68921123D1

公开(公告)日：1995-03-23

申请号：DE68921123

申请日：1989-08-08

Applicant: IBM

Inventor： SEKIYA KAZUO ,  SHIRAISHI YUICHI

IPC: H04N1/40 ,  G06T5/00 ,  G09G5/00 ,  G09G5/391 ,  H04N1/41 ,  G09G1/16 ,  G06T1/00

Abstract: A display system for converting first gray level signal of N bits (N is integer larger than or equal to 2) representing 2 gray levels to second gray level signal representing 2 gray levels (M is integer satisfying N>M>/=1) : said display system comprising: means for separating said first gray level signal of N bits into higher M bits and lower N-M bits; 2 tables each of which stores P x Q modification values satisfying P x Q >/= 2 ; means for selecting one of said tables by using said NM bits; means for adding said M bits and each of modification values of said selected table to generate P x Q second gray level signals; and means for supplying said second gray level signals to a display device of 2 gray levels.

公开(公告)号：DE68918911D1

公开(公告)日：1994-11-24

申请号：DE68918911

申请日：1989-08-08

Applicant: IBM

Inventor： SEKIYA KAZUO SUNHEIM ASAMI ,  SHIRAISHI YUICHI

IPC: H04N1/40 ,  G09G5/00 ,  G09G5/10 ,  H04N1/407

Abstract: A method for use in a digital data display system for converting selected M gray levels in a K-gray scale to an N-gray scale (where K>N>/=M) comprising: a stage of creating a first table in which each of said M gray levels is mapped, in accordance with the order and magnitude of the relative brightness in the K-gray scale, in different M gray levels in the N-gray scale, and a stage of creating a second table in which the M gray levels in the N-gray scale mapped in said first table is mapped correspondingly to the M gray levels in said K-gray scale.