This paper proposes a systematic construction algorithm for the fixed block-length (d, k) code, which is important as the code for magnetic recording. The coding rate (coding efficiency) and the encoding/decoding algo...
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This paper proposes a systematic construction algorithm for the fixed block-length (d, k) code, which is important as the code for magnetic recording. The coding rate (coding efficiency) and the encoding/decoding algorithms are discussed. As a result of numerical calculation for the coding rate of the finite block-length (d, k) code, it is very close to the capacity limit even for a relatively short block-length code. It is shown also that the coding rate for the infinite block length agrees with the capacity. A systematic encoding/decoding algorithm for the finite block-length (d, k) code is proposed, and it is shown that the algebraic encoding/decoding can be realized. By introducing the concept of state, the coding efficiency of fd, k) code can be improved drastically and the coding rate approaches very close to the capacity while observing the constraint for the (d, k) code. Although it can be applied for the peak-shift error correcting (d, k) code, it is left for future study.
More efficient data compression can be achieved in encoding line drawings by vector chain coding (VCC) than by the traditional runlength coding (RLC), provided the total length of the lines within a line drawing is no...
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More efficient data compression can be achieved in encoding line drawings by vector chain coding (VCC) than by the traditional runlength coding (RLC), provided the total length of the lines within a line drawing is not excessive. More bandwidth or time can thus be saved in transmitting such pictures by using VCC. Although this has so far been established only intuitively, quantitative analysis and comparison of the coding efficiency of these two codes for line drawings are performed in this paper. The coding efficiency is measured in terms of both per-length coding rate and data compression ratio, which are determined for a class of handwritten line drawings characterised by a proper statistical model. In particular, the critical point of line drawing complexity is derived at which VCC becomes less efficient than RLC. Experimental observations are also presented to verify the theoretical results.
If a continuous straight line segment is digitized on a regular grid, obviously a loss of information occurs. As a result, the discrete representation obtained (e.g., a chaincode string) can be coded more conveniently...
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If a continuous straight line segment is digitized on a regular grid, obviously a loss of information occurs. As a result, the discrete representation obtained (e.g., a chaincode string) can be coded more conveniently than the continuous line segment, but measurements of properties (such as line length) performed on the representation have an intrinsic inaccuracy due to the digitization process. In this paper, two fundamental properties of the quantization of straight line segments are treated. 1) It is proved that every ``straight"" chaincode string can be represented by a set of four unique integer parameters. Definitions of these parameters are given. 2) A mathematical expression is derived for the set of all continuous line segments which could have generated a given chaincode string. The relation with the chord property is briefly discussed.","doi":"10.1109/TPAMI.1984.4767550","publicationTitle":"IEEE Transactions on Pattern Analysis and Machine Intelligence","startPage":"450","endPage":"463","rightsLink":"http://***/AppDispatchServlet?publisherName=ieee&publication=0162-8828&title=Discrete+Representation+of+Straight+Lines&isbn=&publicationDate=July+1984&author=Leo+Dorst&ContentID=10.1109/TPAMI.1984.4767550&orderBeanReset=true&startPage=450&endPage=463&volumeNum=PAMI-6&issueNum=4","displayPublicationTitle":"IEEE Transactions on Pattern Analysis and Machine Intelligence","pdfPath":"/iel5/34/4767540/***","keywords":[{"type":"IEEE Keywords","kwd":["Quantization","Low earth orbit satellites","Length measurement","Performance evaluation","Disruption tolerant networking","Laboratories","Physics","Pathology","Biomedical informatics","Encoding"]},{"type":"Author Keywords ","kwd":["quantization error","Chaincode string","chord property","coding efficiency","digitized straight lines"]}],"allowComments":false,"pubLink":"/xpl/***?punumber=34","issueLink":"/xpl/***?isnumber=4767540","standardTitle":"Discrete Representation of St
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