JPH05221043A - Network output device - Google Patents

Abstract

PURPOSE:To enhance the output speed of printing by enhancing the reutilization factor the dot pattern stored in a font cache. CONSTITUTION:A printer 1 is jointly used from a plurality of the output demand devices connected to a local network. In the printer l, vector data is outputted from a vector data memory part 14 corresponding to an inputted character code to be converted to a dot pattern in a vector operation part 15 and the dot pattern is stored in a font cache 16. No vector operation is executed with respect to the character already stored in the font cache 16 and the stored dot pattern is fetched to perform printing. Frequency control tables 20, 21 storing the use frequencies of a character at every user are provided to the printer 1 and the dot pattern of the font cache 16 is replaced using said tables.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network output device such as a printing device which can be jointly used by a plurality of output requesting devices connected to a network.

[0002]

2. Description of the Related Art Conventionally, in a printing device in a Japanese word processor or the like, a vector font that represents one character by combining vector data, and one character with a set of dots of 24 × 24 to 56 × 56 dots is used. Either one or both of the dot fonts representing the pattern are adopted. Among them, the vector font has the advantage that the outline can be printed nicely even if the character is enlarged greatly, but when comparing characters of standard size, it is easy for characters with a large number of strokes to be crushed. , It may be inferior to the dot font. On the other hand, the dot font enables clear printing of standard size characters, but has the drawback that when the characters are greatly enlarged, the jagged edges of the outline are noticeable and unsightly. As described above, since the vector font and the dot font each have advantages and disadvantages, printing is performed by using both of them.

In a vector font, when a character is requested to be printed, vector data corresponding to the character code is read from the vector data storage unit,
Perform vector operations. Based on the calculation result, the contour of the character is drawn and the inside of the contour is painted, and the obtained dot pattern is printed. At this time, if the vector data is read, the vector is calculated, the contour is drawn, and the inside of the contour is filled every time a character is requested to be printed, the printing speed is reduced. Further, the dot pattern in the dot font is stored in the dot font storage section, and when a character is requested to be printed, the dot pattern corresponding to the character code is read from there and printed. At that time, when a magnetic disk is used as the dot font storage unit, the access speed to the magnetic disk is slow, so if you try to read from the magnetic disk every time there is a character printing request, the printing speed will decrease. I will end up.

Therefore, for both the vector font and the dot font, the obtained dot pattern is stored in the font cache and is read from the font cache from the second time onward to improve the printing speed. Conventionally, such a printing apparatus has also been used as a network printing apparatus that can be jointly used by a plurality of computers connected to a local network.

FIG. 7 is a block diagram showing an outline of a conventional network printing apparatus. In FIG. 7, 1 is a printing device, 2 and 3 are workstations, 4 is a computer, 5 is a facsimile device, 6 is a terminal device, 7 is a network, 11 is a printer control unit, 12 is a network control unit, and 13 is a dot. A font storage unit, 14 is a vector data storage unit, 15 is a vector calculation unit, 16 is a font cache, 17 is a cache management table, 18 is a page memory, and 19 is a printing unit.

In this printing apparatus, for example, when a print request is issued from the workstation 2 to the printing apparatus 1, the vector data read from the vector data storage unit 14 is sent to the vector calculation unit 15 in accordance with the character code. The dot patterns are inserted to form dot patterns, or the dot patterns are read from the dot font storage unit 13 and temporarily stored in the font cache 16. However, since the capacity of the font cache 16 is limited (usually 1 to 2 MB), it is not possible to store all dot patterns. So font cache 1
When a new dot pattern is stored after 6 is full, it is necessary to expel any dot pattern from the ones stored so far.

For that purpose, until now, the font cache 1
It is necessary to select which dot pattern is to be expelled from the ones stored in 6. There are several conventional selection methods, and one of them is, for example, a FIFO (First In FIRS).
t out) method. According to this method, the oldest one stored in the font cache 16 is swept first. According to this method, the system can be simplified, but if it becomes old, it will be ejected even if it is used frequently, and the reuse rate of the dot pattern (data stored in the cache will be reused). The higher the ratio, the worse the printing speed).

[0008] As another example, LRU (Least
There is a Recent Used method. This LR
In the U method, of the fonts stored in the font cache 16, the one with the oldest used time is swept first. According to this method, the less frequently used ones are inevitably sequentially ejected, so that the most frequently used ones are left in the font cache 16 and the reuse rate of the dot pattern is improved. ..

As a conventional document relating to a printing apparatus having such a font cache, there is JP-A-2-272492.

[0010]

[Problems to be Solved by the Invention]

(Problem) However, in the above-mentioned conventional technique, F
Whether the IFO method or the LRU method is used, in the case of a network printing apparatus that is used by a plurality of users jointly, it is not considered that there is a bias in the usage frequency for each user. There is a problem that the reuse rate becomes low and the printing speed becomes slow.

(Explanation of Problems) In a network printing apparatus in which a plurality of users jointly use, since the vocabulary used varies depending on the content of work and an individual, the type of characters frequently used changes every time the user changes, As a result, the reuse rate of the dot patterns stored in the font cache 16 becomes low. That is, when the user A prints immediately after the user B prints, the tendency of the characters to be used is different. Therefore, the dot pattern stored in the font cache 16 when the character A is printed is adjusted according to the tendency of the B usage. It is necessary to replace them one by one.

However, unlike the conventional one, if there is no bias in the usage frequency of each user,
At first, the replacement is performed according to the frequency tendency when A is used, and it does not easily match the frequency tendency of B. Therefore, the reuse rate of the dot pattern of the font cache 16 is low. An object of the present invention is to solve the above problems.

[0013]

In order to solve the above problems, according to the present invention, a dot outputting a dot pattern corresponding to a character type code in a network output device which can be used jointly by a plurality of output requesting devices. A pattern output unit, a font cache for storing the dot pattern, a user storage unit for storing which user on the network is accessing the user,
Based on the frequency management means for storing the character usage frequency for each user and the character usage frequency stored in the user storage means among the character usage frequencies stored in the frequency management means. The dot pattern replacement management means for managing the replacement of the dot patterns stored in the font cache is provided.

[0014]

[Operation] A user storage means for storing which user on the network is accessing and a frequency management means for storing the frequency of use of characters for each user are provided. Then, based on the frequency of use of characters stored in the frequency management means, the frequency of use of user characters stored in the user storage means is used to manage the replacement of the dot patterns stored in the font cache. I did it. As a result, when another user tries to output immediately after printing, even if the vocabulary used depends on the content of work and individual, the characters in the font cache are output based on the usage frequency of the user who is currently outputting. Is replaced, it is possible to efficiently replace the one that matches the usage frequency of the user who is currently outputting. Therefore, the reuse rate of the dot pattern of the font cache is high and the output speed is improved.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an outline of a network printing apparatus of the present invention. The reference numerals correspond to those in FIG. 7, and 20 and 21 are frequency management tables. The frequency management tables 20 and 21 are frequency-managed for each user, and A and B correspond to the users A and B of the workstations 2 and 3, respectively. Also, in that case,
"For each user" can be various cases such as each workstation, each section, or each individual.
Then, in which of these units the frequency management table is provided can be appropriately selected as necessary.

FIG. 2 is a diagram showing an example of the cache management table. In Figure 2, "dot pattern area"
Is a number in which the area in the font cache 16 is divided for each dot pattern and numbers are given in order. The “character type code” is a code corresponding to the type of character.
The “update bit” is a number that serves as an indicator of how long the character has been unused for a certain period of time. The "next ejection candidate" indicates the bit pattern with the largest update bit. The character type code in the cache management table is updated every time a new dot pattern is stored in the font cache 16.

The update bit is incremented by 1 at regular intervals. If any dot pattern in the font cache 16 is used, the update bit corresponding to that dot pattern is cleared. To do. Therefore, the dot pattern updating bit that is frequently used is always small, and the dot pattern updating bit that is not frequently used becomes large over time. The dot pattern with the largest update bit is the dot pattern used most recently, and is the next eviction candidate. This is a conventionally known LRU algorithm.

FIG. 3 is a diagram showing an example of the frequency management table. This shows the user A as an example. In FIG. 3, the “character type code” is a code corresponding to the type of character. The “access count” is the number of times the dot pattern corresponding to the character type code is accessed. The “access frequency class” is divided into classes according to the number of accesses.

Various methods can be considered as the method of classifying the access frequency class, but as an example, the method is performed as follows. For example, the access count of the frequency management table is cleared at regular time intervals, and the access count immediately before clearing is used as a reference for classification. For example, the number of times of access 200 times or more is A, the number of times 100 times or more is B, and the number of times less than 100 times is C. At that time, the previous class and the newly applied class are correlated. For example, when the previous class is A and the class newly calculated from the access count is C, instead of directly adopting C,
Considering the correlation with the previous A, it is set to the intermediate B between A and C.

Next, an example of the printing procedure of the present invention will be described with reference to the flowchart when the user A issues a printing request. In the present invention, both the vector font and the dot font can be applied, but here, in order to simplify the explanation, it is assumed that all the characters are converted into the dot pattern using only the vector font. To do.

FIG. 4 is a flow chart showing an example of the printing procedure of the present invention. Step 1 ... User A sends a print request signal for a sentence to the printer 1. Step 2 ... The printing apparatus 1 is made to store that the print request is from A. Step 3: The character type code is extracted in order from the sentence requested to be printed. Step 4 ... Referring to the cache management table 17,
It is determined whether or not the dot pattern corresponding to the character type code is already stored in the font cache 16.

Step 5 ... When not stored, the vector data corresponding to the character type code is taken out from the vector data storage unit 14. Step 6 ... The vector data is converted to the vector calculation unit 15
Input to, vector calculation is performed, and a dot pattern is obtained. Step 7 ... Referring to the cache management table 17,
It is determined whether or not the font cache 16 has an area for storing the dot pattern.

Step 8: When there is no space in the font cache 16, the dot pattern currently stored in the font cache 16 is selected based on the usage frequency of the characters stored in the frequency management table 20 for the user A. One character is selected and it is expelled from the font cache 16. Step 9 ... When the font cache 16 has an empty space at Step 7, or after the dot pattern for one character is emptied to secure the empty space at Step 8, the empty area of the font cache 16 is obtained at Step 6. Stored dot pattern. Step 10: When the dot pattern of the font cache 16 is replaced, the character type code of the cache management table 17 is replaced corresponding to the replaced dot pattern, and the update bit indicates that it has been stored most recently. Set to 1. In step 4, the dot pattern corresponding to the character type code is the font cache 1
If the character type code is stored in 6, the update bit of the character type code is returned to 1. Step 11 ... If the character type code is already registered in the frequency management table 20 for user A, 1 is added to the access count, and if not registered, the character type code is registered and the access count is added. Write 1.

Step 12 ... The dot pattern of the character is fetched from the font cache 16 and developed in the page memory 18. Step 13 ... It is judged whether or not the character has been expanded in the page memory 18 for one page, and if it has been expanded for one page, Step 14 is executed.
Otherwise, go back to step 3. Step 14: The printing unit 19 prints the data developed in the page memory 18. Step 15 ... It is determined whether or not all the requested sentences have been printed. When completed, proceed to step 16, otherwise return to step 3. Step 16 ... At the workstation 2 of user A,
Notify that printing is completed.

Next, based on the usage frequency of the characters stored in the frequency management table 20 for the user A in the above step 8, one character is selected from the dot patterns currently stored in the font cache 16. The processing procedure for selecting and erasing from the font cache 16 will be described in detail.

FIG. 5 is a flow chart showing an example of a procedure for expelling one character from the font cache. Step 1 ... Referring to the update bit of the cache management table 17, the character type code having the maximum update bit is selected. For example, in the case of FIG. 2, since the dot pattern area 3 and the dot pattern area 9 have the maximum update bit 8, the character type codes 12 and 37 are selected. Step 2 ... It is determined whether or not there are a plurality of character type codes selected in Step 1. If there is more than one, proceed to step 3, and if there is only one, proceed to step 4.

Step 3 ... Of the characters selected in Step 1, the character type code having the lowest access frequency of the frequency management table 20 for the user A is selected. For example, in FIG.
In the frequency management table of No. 3, when the access counts of the character type codes 12 and 37 are compared, 130 times and 250 times, respectively.
Since the character type code 12 is smaller in the number of times, that is selected. In this case, only the access frequency class may be viewed and the one having the lowest access frequency class may be selected. Step 4 ... The dot pattern corresponding to the selected character type code is expelled from the font cache 16.

In the above example, the eviction candidates selected using the cache management table are narrowed down to one by using the frequency management table, but the order is changed and the frequency management table is used. It is also possible to use the cache management table to narrow down to one out of the eviction candidates selected in this way.

FIG. 6 is a flow chart showing another example of the procedure for expelling one character from the font cache.

Step 1 ... Select the character type code of the class having the lowest access frequency class in the frequency management table 20 for user A. Step 2 ... It is determined whether or not there are a plurality of selected character type codes. If there are a plurality of selected character type codes, the process proceeds to step 3, and if there is only one, the process proceeds to step 4. Step 3 ... Of the characters selected in Step 1, the character type code having the largest update bit in the cache management table 17 is selected. Step 4 ... The dot pattern corresponding to the selected character type code is expelled from the font cache 16.

The frequency management table can be used in various ways other than the above. For example,
Although the eviction candidate is selected by the LRU method, the FIFO method, etc., if the access frequency class A of the frequency management table is never evacuated, and if the access frequency class A is selected as the eviction candidate, the LRU method, again. FI
The next eviction candidate is selected by the FO method or the like. Ejection candidates are selected by weighting the access frequency class and the selection by the LRU method. For example, the access frequency class A is given 0 points, B is given 10 points, and C is given 20 points, and these are added together with the update bit of the cache management table multiplied by a fixed number. Then, the one having the largest total is selected as the eviction candidate.

In addition to the frequency management table for each user, a frequency management table for all users is also provided, and the character usage frequency for each user and the overall character usage frequency are combined to select an eviction candidate. For example, in the frequency management table for each user, the access frequency class is A
And the access frequency is B in the overall frequency management table.
, The frequency class combining these is AB. And the classes AA, AB, AC, BA, ...
It is defined that the access frequency is high in the order of CC, and the candidates are eviction candidates in the order of low access frequency. In addition, LRU system, FIF
It is also possible to select the eviction candidate using only the frequency management table without combining with the O method or the like.

As described above, various ways of using the frequency management table are conceivable, but it is not possible to say unequivocally which one is most efficient, and which one is adopted is applied. You should choose the most suitable one according to the environment.

Needless to say, the present invention can be similarly applied to the case of outputting to a display device such as a CRT instead of the above-mentioned printing device. The output requesting device may be an electronic computer, a terminal device, a facsimile device, a personal computer, or the like, in addition to the workstation described here.

[0035]

As described above, the network output device of the present invention has the following effects. A user storage means for storing which user on the network is accessing and a frequency management means for storing the character usage frequency for each user are provided. Then, based on the frequency of use of characters stored in the frequency management means, the frequency of use of user characters stored in the user storage means is used to manage the replacement of the dot patterns stored in the font cache. I did it.

As a result, when another user tries to output immediately after outputting by one user, even if the vocabulary to be used is different depending on the content of work and individual, the font is output based on the frequency of use of the user who is currently outputting. Since the characters in the cache are replaced, it is possible to efficiently replace the characters that match the frequency of use of the user who is currently outputting. Therefore, the reuse rate of the dot pattern of the font cache is increased and the output speed is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of a network printing apparatus of the present invention.

FIG. 2 is a diagram showing an example of a cache management table.

FIG. 3 is a diagram showing an example of a frequency management table.

FIG. 4 is a flowchart showing an example of a printing procedure of the present invention.

FIG. 5 is a flowchart showing an example of a procedure for expelling one character from the font cache.

FIG. 6 is a flowchart showing another example of the procedure for expelling one character from the font cache.

FIG. 7 is a block diagram showing an outline of a conventional network printing apparatus.

[Explanation of symbols]

1 ... Printing device, 2, 3 ... Workstation, 4 ...
Computer, 5 ... Facsimile device, 6 ... Terminal device, 7
... network, 11 ... printer control unit, 12 ... network control unit, 13 ... dot font storage unit, 14 ... vector data storage unit, 15 ... vector operation unit, 16 ... font cache, 17 ... cache management table, 1
8 ... page memory, 19 ... printing section, 20, 21 ... frequency management table

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location G09G 5/22 9061-5G

Claims (1)

[Claims] 1. A network output device that can be used jointly by a plurality of output requesting devices, a dot pattern output means for outputting a dot pattern corresponding to a character type code, and a font cache for storing the dot pattern. A user storage unit that stores which user on the network is accessing the data, a frequency management unit that stores the frequency of character usage for each user, and a frequency of character usage stored in the frequency management unit. A network output device, comprising: dot pattern replacement management means for managing replacement of dot patterns stored in the font cache based on the frequency of use of characters of the user stored in the user storage means. ..