公开(公告)号：AU508981B2

公开(公告)日：1980-04-17

申请号：AU3161477

申请日：1977-12-15

Applicant: IBM

Inventor： JUDD I D ,  MINSHULL J F

IPC: G06F3/12 ,  G06K9/54 ,  G06T3/00 ,  G06T9/20 ,  G09G5/24 ,  H04N1/04

Abstract: 1517869 Image encoding apparatus INTERNATIONAL BUSINESS MACHINES CORP 20 Dec 1976 53034/76 Heading H4P Data in the form of a stream of bits representing picture elements (pels), derived from the raster scanning of a document 1, is stored in compressed form in a store 8 which can be accessed so that the data pertaining to the stored document can be transmitted to a receiver 13 or can be expanded in a decompressor 9 for plotting or printing by a plotter 10 or for display on a display unit. The required compression is effected by passing the original bit stream through a pel stripper 3 where bits are removed to leave a processed bit pattern in which the bits represent predominantly single-pel-width strokes constituting either the outlines or the centre lines of characters. A segment follower 6 detects contiguous bits and produces a series of segments representing the tracked strokes. Each segment is coded in an encoder 7 into code words representing the shape of the segments and code words representing the end points of the segments, the segment bit thus produced being stored in the store 8. The stripping process is described with reference to Fig. 2 (not shown), whilst the constraints which determine whether a pel is or is not stripped from the original bit stream are described with reference to Figs. 5 and 6 (not shown). Suitable arrangements for the units 3, 6 and 7 are described with reference to Figs. 7 to 13 (not shown).

公开(公告)号：AU511040B2

公开(公告)日：1980-07-24

申请号：AU3165977

申请日：1977-12-16

Applicant: IBM

Inventor： EVANS J M ,  JUDD I D ,  LOVIE R H ,  MINSHULL J F

IPC: H04N5/262 ,  G06K9/54 ,  G06T3/00 ,  G06T9/20 ,  G06T11/20 ,  G09G5/36 ,  H04N1/411 ,  H04N1/02 ,  H04N1/04

Abstract: Graphical data on a document is raster scanned and the resulting bit pattern is processed to provide a processed bit pattern which represents lines which each are a single pel in width and indicative of the shapes of objects scanned on the document. These single pel wide lines may represent the outlines of objects on the center lines. The processed bit pattern is then directed to a line follower in which bits representing contiguous pels are detected and tested for linearity. When contiguous pels fail the linearity test, a new vector is started and the vector being tracked is terminated. Hardware for performing these operations is described. The resulting vector list is stored until needed for display. Optionally a display station can be used to correct faulty vectors or to encode alphanumeric data in a more convenient format than vector coding.