公开(公告)号：CA1291821C

公开(公告)日：1991-11-05

申请号：CA544052

申请日：1987-08-07

Applicant: IBM

Inventor： LANGDON GLEN G JR ,  MITCHELL JOAN L ,  PENNEBAKER WILLIAM B ,  RISSANEN JORMA J

IPC: G06T9/00 ,  H03M7/40

Abstract: YO986-091 Apparatus and method for compressing and de-compressing binary decision data by arithmetic coding and decoding wherein the estimated probability Qe of the less probable of the two decision events, or outcomes, adapts as decisions are successively encoded. To facilitate coding computations, an augend value A for the current number line interval is held to approximate one by renormalizing A whenever it becomes less than a prescribed minimum AMIN. When A is renormalized, the value of Qe is up-dated. The renormalization of A and up-dating of Qe are preferably based on a single-bit test. Also, each Qe value is preferably specified as a 12-bit value having the least significant bit set to 1 and having no more than four other bits set to 1. The number of Qe values in the 1/4 to 1/2 probability range is enhanced to improve coding efficiency. A decision coding parameter of preferably six bits indicates the sense of the more probable symbol (MPS) in one bit and identifies a corresponding Qe value with the remaining five bits. In addition to probability adaptation, the present invention discloses an allocation of bits in a code stream register in which preferably two spacer bits are inserted between a next byte portion (which contains a byte of data en route to a buffer) and a fractional portion which may be involved in further computation. With the two spacer bits, any code greater than or equal to Hex 'CO' which fol YO986-091 lows a Hex 'FF' byte is illegal for data and therefore provides for an escape from the code stream. The two spacer bits also reduce the number of stuff bits inserted to account for carry or borrow propagation. Encoding and decoding can be performed interchangeably by hardware or software which feature differing coding conventions.

公开(公告)号：CA1236563A

公开(公告)日：1988-05-10

申请号：CA472899

申请日：1985-01-25

Applicant: IBM

Inventor： MITCHELL JOAN L ,  PENNEBAKER WILLIAM B

IPC: H04N5/21 ,  G09G1/00 ,  G09G1/16 ,  G09G5/00 ,  G09G5/10 ,  H04N5/20 ,  H04N5/44

Abstract: A method, embodying the present invention, for suppressing the perception of flicker in interlaced video images, includes the steps of: testing, each pixel in an image, for an intensity value below a first predetermined threshold; modifying, for each tested pixel, an intensity value representation for each nearest neighbor pixel along a first axis of said interlaced image having an intensity value exceeding a second predetermined threshold, if the intensity value of the tested pixel is below the first predetermined threshold; displaying, on a video display device, an interlaced image generated by the steps of testing and modifying, having a suppressed perception of flicker.

公开(公告)号：CA1232356A

公开(公告)日：1988-02-02

申请号：CA468560

申请日：1984-11-23

Applicant: IBM

Inventor： ANDERSON KAREN L ,  GOERTZEL GERALD ,  MITCHELL JOAN L

IPC: H04N1/41 ,  G06F3/14 ,  G06T9/00 ,  H03M7/46 ,  H04N1/419

Abstract: A method for converting an image from a bit map to a run end or run length representation includes the steps of: storing said image as a bit map representation; initializing all variables to be used in the conversion process; converting by table lookup, each run of continuous color to a run end; storing, in a run end buffer, as a count value, each run end; repeating the steps of converting and storing for each run of continuous color to the end of the image.

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

公开(公告)号：CA1082296A

公开(公告)日：1980-07-22

申请号：CA270284

申请日：1977-01-24

Applicant: IBM

Inventor： MITCHELL JOAN L ,  PENNINGTON KEITH S ,  HOCHBERG FREDERICK

IPC: B41F17/00 ,  B41J2/01 ,  B41J2/22 ,  B41J2/27 ,  B41J2/295 ,  B41J2/305 ,  B41J2/32 ,  B41M5/10 ,  B41M5/382 ,  B41J3/20 ,  G01D9/00

Abstract: ULTRASONIC TRANSFER PRINTING WITH MULTI-COPY, COLOR AND LOW AUDIBLE NOISE CAPABILITY A printing or copying system in which ink is transferred from an ink-bearing medium to a printing medium through the use of ultrasonics. The ink-bearing medium may be an ink ribbon, carbon paper or the like which is in contact with a printing medium such as paper. Ultrasonic energy is applied to the ink-bearing medium through transmission fibers, wires or bundles thereof, causing the viscosity of the ink to be reduced due to the ultrasonic vibrations and conversion of the ultrasonic energy into heat such that the ink is transferred to the printing medium. Multi-copy capability is achieved by having alternate layers of carbon paper or the like in contact with the paper.