Method and device for selecting a character shape for each character of a text, e.g. of Arabic, according to four classes

Claim 3

A method as claimed in Claim 1, further comprising the step of preliminarily regarding each of spaces as an independent character of said first class, said spaces being next backwardly and forwardly adjacent to each word in said sequence.

Claim 4

A method as claimed in Claim 2, wherein said first step comprises the steps of: assigning a backward and a forward linking characteristic to each independent character of said set, the backward and the forward linking characteristics being indicative of whether or not an independent character of said set has a capability of linking to next backwardly and forwardly adjacent independent characters in a succession of words, respectively; and classifying the independent characters of said set into said first through said third classes when both of the backward and the forward linking characteristics of an independent character of said set do not indicate the capability, when the backward linking characteristic of an independent character of said set indicates the capability while the forward linking characteristic thereof does not, and when both of the backward and the forward linking characteristics of an independent character of said set indicate the capability, respectively.

Claim 5

A method as claimed in Claim 1, the character shapes of each character of said set being an isolated, an initial, a medial, and a final shape, wherein said third step comprises the steps of: selecting, the isolated, initial, medial, and final shapes when said first one of the first through the third classes is either of said first and said second classes while said second one of the first through the third classes is said first class, when said first one of the first through the third classes is either of said first and said second classes while said second one of the first through the third classes is either of said second and said third classes, when said first one of the first through the third classes is said third class while said second one of the first through the third classes is either of said second and said third classes, and when said first one of the first through the third classes is said third class while said second one of the first through the third classes is said first class, respectively.

Claim 6

A character shape selecting device for processing a sequence of characters to select character shapes for the respective characters, each character being included in a character set and having a dependability and a backward and a forward linking characteristic, the dependability being indicative of whether a character of said set is an independent or a dependent character, the backward and the forward linking characteristics being indicative of whether or not a character of said set has a capability of linking to next backwardly and forwardly adjacent independent character in a succession of words, respectively, said character shape selecting device comprising: a source data buffer for storing the characters of said sequence: a character attribute table for storing the dependabilities and the backward and the forward linking characteristics for the respective characters of said set; a character shape table for storing character shapes for each character of said set and for the backward 'and the forward linking characteristics of the independent characters of said set; first accessing means for accessing said source data buffer to successively specify a plurality of characters in said sequence while accessing said character attribute table by the successively specified characters to detect the dependabilities and the backward and the forward linking characteristics of the successively specified characters and to locate next backwardly and forwardly adjacent independent characters in the successively specified characters for each of said successively specified characters; and second accessing means coupled to said first accessing means for accessing said character shape table by said each of the successively specified characters, the backward linking characteristic of said next forwardly adjacent independent character, and the forward linking characteristic of said next backwardly adjacent independent character-to select one of the character shapes for said each of the successively specified characters.

Claim 7

A character shape selecting device for processing a sequence of characters to select character shapes for the respective characters, each character being included in a character set and having a dependability and a backward and a forward linking characteristic, the dependability being indicative of whether a character of said set is an independent or a dependent character, the backward and the forward linking characteristics being indicative of whether or not a character of said set has a capability of linking to next backwardly and forwardly adjacent independent character in a succession of words, respectively, said character shape selecting device comprising: a source data buffer for storing the characters of said sequence: a character attribute table for storing the dependabilities and the backward and the forward linking characteristics for the respective characters of said set; a character shape table for storing character shapes for each character of said set and for the backward 'and the forward linking characteristics of the independent characters of said set; first accessing means for accessing said source data buffer to successively specify a plurality of characters in said sequence while accessing said character attribute table by the successively specified characters to detect the dependabilities and the backward and the forward linking characteristics of the successively specified characters and to locate next backwardly and forwardly adjacent independent characters in the successively specified characters for each of said successively specified characters; and second accessing means coupled to said first accessing means for accessing said character shape table by said each of the successively specified characters, the backward linking characteristic of said next forwardly adjacent independent character, and the forward linking characteristic of said next backwardly adjacent independent character-to select one of the character shapes for said each of the successively specified characters.

Claim 8

A character shape selecting device as claimed in Claim 5, wherein each dependent character of said set is regarded as having the capability of linking to both next backwardly and forwardly adjacent independent characters.

Claim 9

A character shape selecting device as claimed in Claim 6, wherein each of spaces next backwardly and forwardly adjacent to each word in said sequence is regarded as one of the independent characters of said set that has the capability of linking to neither of next backwardly and forwardly adjacent independent characters.

Claim 10

A character shape selecting device as claimed in Claim 7, wherein said second accessing means comprises: a current character register; a character attribute register; a forward linking characteristic register: first means coupled to said first accessing means for storing said each of the successively specified characters in said current character register as a currently processed character, for storing the backward linking characteristic of said next forwardly adjacent independent character in said character attribute register as a forwardly adjacent backward linking characteristic, and for storing the forward linking characteristic of said next backwardly adjacent independent character in said forward linking characteristic register as a backwardly adjacent forward linking characteristic; and second means for accessing said character shape table by said currently processed character, said forwardly adjacent backward linking characteristic, and said backwardly adjacent forward linking characteristic to select said one of the character shapes.

Claim 11

A character shape selecting device as claimed in Claim 8, further comprising-: start signal producing means for producing a start signal upon start of operation of said character shape selecting device: a clock generator put into operation by said start signal and responsive to the dependability detected from time to time by said first accessing means as a current 'dependability for producing a plurality of timing signals in cycles, said timing signals including a predetermined timing signal and an additional timing signal which follows said predetermined timing signal when the current dependability indicates a dependent character; said first accessing means being responsive to said start and said timing signals for accessing said source data buffer and said character attribute table; said first means being responsive to said start signal and to preselected ones of said timing signals for loading said current character register, said character attribute register, and said forward linking characteristic register with said currently processed character, said forwardly adjacent backward linking characteristic, and said backwardly adjacent forward linking characteristic, respectively; said second means being responsive to a prescribed one of said timing signals for accessing said character shape table.

Claim 12

A character shape selecting device as claimed in Claim 9, wherein the timing signals produced in an opening cycle which next follows said start signal are first through fourth timing signals, the timing signals produced in each of other successive cycles being the second through the fourth timing signals, said predetermined and said prescribed timing signals being the third and the fourth timing signals, respectively.

Claim 13

A character shape selecting device as claimed in Claim 10, wherein: said source data buffer has a plurality of addresses for storing the characters of said sequence, said addresses being consecutively numbered starting at a predetermined number which is regarded as zero, the address numbered zero being for storing a foremost character in said sequence: said first accessing means comprising: address specifying means cleared by said start signal to specify the address numbered zero and thereafter for stepwise specifying other addresses in response to the first through the third timing signals of said opening cycle and to the second and the third timing signals of each of said other successive cycles with that address again specified by the fourth timing signal of each of said opening and said other successive cycles which is meanwhile specified by the second timing signal, the additional timing signal, when produced, specifying that one of the addresses which is next consecutive to the address specified by the predetermined timing signal; character producing means responsive to every timing signal of each of said opening and said other successive cycles for accessing said source data buffer to produce those characters as the successively specified characters which are storedin the addresses specified by said address specifying means; and attribute producing means responsive to the predetermined timing signals of said opening and said other successive cycles for successively accessing said character attribute table by the successively specified characters to produce the dependabilities and the backward and the forward linking characteristics for the successively specified characters.

Claim 14

A character shape selecting device as claimed in Claim 11, wherein said address specifying means comprises: an address register having a count for specifying the address of a number which is equal to the count, said address register being cleared by said start signal to specify the address numbered zero; a subsidiary register; means responsive to the first through the third timing signals of said opening cycle and to the second and the third timing signals of each of said other successive cycles for counting up the count in said address register; means responsive to the predetermined timing signal of each of said opening and said other successive cy-cles for transferring the count from said address register to said subsidiary register; and means responsive to the fourth timing s:ignal of each of said opening and said other successive cycles for transferring the count from said subsidiary register back to said addtress register.

Claim 15

A character shape selecting device as claimed in Claim 11, wherein said first means comprises: means coupled to said character producing means and responsive to the second timing signal of each of said opening and said other successive cycles for storing that character in said current character register as said currently processed character which is produced from the address specified by each of the first; timing signal and those second timing signals Which are produced one cycle earlier than said other successive cycles: means coupled to said attribute producing means and responsive to the second timing signal of said opening cycle and to the predetermined timing signals of said opening and said other successive cycles for loading from time to time said character attribute register with those backward linking characteristics as said forwardly adjacent backward linking characteristic which are produced in response to the second timing signals of said opening cycle and to the predetermined timing signals of said opening and said other successive cycles, respectively; means responsive to said start signal for clearing said forward linking characteristic: register to make the backwardly adjacent forward linking characteristic indicate the incapability; forward linking characteristic loading means coupled to said character attribute register and responsive to the fourth timing signals of said opening cycle and of specified ones of said other successive cycles for loading said forward linking characteristic register, as said backwardly adjacent forward linking characteristic, successively with the forward linking characteristics stored in said character attribute register in response to the second timing signal of said opening cycle and to the predetermined timing signals produced one cycle before said specific ones of the other successive cycles, said specific ones of t:he other successive cycles being one cycle earlier than the other successive cycles except those of said other successive cycles in each of which said additional timing signal is produced.