JP2708441B2 - Handwritten character recognition device with input procedure teaching function - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an online handwritten character recognition device, and more particularly to an online handwritten character recognition device suitable for teaching an input procedure of a character pattern registered in a dictionary. . [Prior Art] In an online handwritten character recognition device, it is general to perform pattern recognition using the number of strokes and the stroke order as one of effective information. This is because the device is small, inexpensive, and can be recognized at a practical speed. Therefore, unless the number of strokes registered in the dictionary pattern and the stroke order are input, a high recognition rate cannot be obtained. Of course, improvements have been made in the recognition algorithm, such as making one of the number of strokes or the stroke order free, but the definitive method has not yet been obtained. On the other hand, from the standpoint that the number of strokes and the stroke order are relatively stable from the standpoint of an individual, a handwritten character recognition device that obtains a high recognition rate using a personal dictionary has recently been devised. For example, as described in JP-A-60-8991,
At the time of misrecognition, input the character code and display the number of strokes of the character and the input procedure of the stroke order from the dictionary. Is disclosed. As described above, in the conventional apparatus, as a teaching method of the input procedure of the registered dictionary pattern, a method of displaying a number indicating a stroke input order together with a character pattern on a display device has been adopted. [Problems to be Solved by the Invention] The above-mentioned conventional technology has a problem that the input procedure of the dictionary pattern is taught dynamically and the direction of the stroke order is not considered, and the input procedure cannot be grasped intuitively. Was. An object of the present invention is to provide a handwritten character recognition device with an input procedure teaching function for intuitively teaching an operator of an input procedure of a designated character in a dictionary pattern. [Means for Solving the Problems] The above object can be achieved by displaying the stroke order of a specified character pattern at a speed that can be understood by an operator. Therefore, the present invention provides a tablet for inputting a handwriting stroke, a pattern storage unit in which a plurality of character patterns formed by a stroke composed of a plurality of coordinate point sequences are registered, and an input handwriting stroke in the pattern storage unit. In a handwritten character recognition device having at least a recognition means for comparing and recognizing a registered character pattern and a display device for displaying the recognized result, a character pattern registered in a pattern storage section is selected, and the selection is performed. When displaying the strokes forming the character pattern according to the stroke order, a control means is provided for displaying a plurality of coordinate point sequences constituting the strokes with a certain delay in the stroke order. Further, the present invention provides a tablet for inputting a handwriting stroke, a pattern storage unit in which a plurality of character patterns constituted by strokes composed of a plurality of coordinate point sequences are registered, and an input handwriting stroke in the pattern storage unit. In a handwritten character recognition device having at least a recognition means for comparing and recognizing a registered character pattern and a display device for displaying the recognized result, a character pattern registered in a pattern storage section is selected, and the selection is performed. Strokes constituting the character pattern obtained at least twice in the stroke order,
It is characterized by having control means for displaying at different display speeds. [Operation] The present invention selects a character pattern registered in the pattern storage unit, and displays strokes constituting the selected character pattern in the stroke order, according to the stroke order. By delaying the display, the operator can understand where one stroke starts, proceeds in which direction, and ends where. In addition, by selecting a character pattern registered in the pattern storage unit and displaying strokes constituting the selected character pattern at least twice at different display speeds according to the stroke order, while viewing the final character pattern,
With the slow movement, the same character pattern can be displayed to the operator, and the operator can understand the stroke order of the character pattern. In this manner, by displaying the stroke order of the designated character pattern at a speed that can be understood by the operator, the stroke order of the character pattern can be understood. [Embodiment] An embodiment of the first invention of the present invention will be described below with reference to FIGS.
This will be described with reference to FIG. FIG. 1 is a block diagram of an embodiment of the present invention. In FIG. 1, 1 is a tablet for inputting stroke coordinates,
2 means for storing handwritten strokes from the tablet (TB) in the memory; 3 for comparing the inputted handwritten strokes with the dictionary pattern 4 to recognize characters or to create and register a new dictionary; A dictionary creating means, 4 is a dictionary pattern storing feature amounts necessary for character recognition and trace display,
Reference numeral 5 denotes a trace character selecting means for selecting a character to be trace-displayed by the operator using the coordinate information of TB1, and 6 calculates coordinates required for trace display from the dictionary pattern 4 of the character selected in 5. Trace coordinate calculation means 7 is a trace display means for displaying the trace coordinates calculated in 6 on the display device 8. FIG. 1 shows an example in which the tablet 1 and the display device 8 are physically separated from each other. However, the tablet 1 and the display device 8 may be integrated into an image input by a pencil on paper. Blocks 1, 2, 3, 4, and 8 are constituent blocks of a conventional handwritten character recognition device.The details thereof are disclosed in, for example, the above-mentioned Japanese Patent Application Laid-Open No. 60-8991. Detailed description is omitted. The characteristic components of the first invention, which is the present invention, are shown in FIG.
Block 7 First, when the operator wants to grasp the input procedure of a specific character in the dictionary patterns created in blocks 2 and 3, first, the tablet 1 is moved from the trace character selecting means 5 and the dictionary pattern 4 to the second pattern. As shown in the screen display in the figure, a cursor is placed on a character to be traced and picked, thereby selecting a trace character. In the example of FIG. 2, the screen display is displayed in the order of the number of strokes, as shown in FIG. 2, in order to facilitate the selection of a character in which five "concave" registered character patterns are selected. In general, patterns required for trace display are often character fonts or recognition patterns created by individuals, and many patterns do not pay much attention to the stroke order and the number of strokes. Therefore, it is often managed separately from a standard dictionary pattern. Note that the registered characters in FIG. 2 are copy-written character patterns output at the time of recognition, and the character patterns to be trace-displayed are registered character patterns created for recognition. In general, the clear copy character pattern and the registered character pattern are almost the same pattern, but may be different. For example, the registered character pattern “O” and the registered character pattern “O”
The image may be registered and associated. In other words, when the “concave” copy-written character pattern is selected, the input procedure of the registered character pattern of “Oh” is traced and displayed. Next, the trace coordinate calculation means of block 6 calculates the trace coordinates required for trace display from the feature dictionary of the selected copy-written character pattern. This can be obtained by calculating the time of a straight line or a circular arc from the feature dictionary and calculating the interpolation coordinates between two points. Next, the display device 8 is sequentially displayed by the trace display means of the block 7 so that the operator can understand the trace coordinates calculated by the block 6. FIG. 3 and FIG. 4 show examples of trace display of the registered character pattern of “concave”. FIG. 3 (a) shows a state where the trace display has been completed up to the timing t with the “concave” registered character pattern.
The trace display of the remaining stroke of the fourth stroke and the stroke of the fifth stroke is not traced. FIG. 4B is a diagram in which trace display of all strokes has been completed. In FIG. 3, SNO is a sequence number indicating the stroke trace order, which corresponds to the stroke order. On the other hand, an end mark EOM is displayed along with the end coordinates of the stroke as a mark indicating the direction of the stroke order. S ₁ ~S ₅ is a line number of stroke. FIGS. 4A and 4B are examples in which the stroke order is displayed together with the start coordinates of the stroke. As a method of displaying the stroke order direction other than those shown in FIGS. 3 and 4, a direction mark may be displayed at arbitrary intermediate coordinates or peripheral coordinates other than the start and end point coordinates of the stroke. FIG. 5 shows an example of the structure of the dictionary pattern 4, which is shown as an example of a "concave" pattern. As shown in FIG. 5, the dictionary pattern is made up of feature point coordinates (P _{i1 to} P _i6 ) and feature parameters (S _{i1 to} S _i5 ) for each i-stroke, and shows only the first stroke in detail. . The configuration and contents of the dictionary vary depending on the recognition algorithm. Here, points obtained by dividing the stroke into five equal parts are set as feature point coordinates (six points), and parameters for interpolating between the feature point coordinates are used as feature parameters. FIG. 6 shows the types of characteristic parameters. In one embodiment of the first invention of the present invention, two types of line types and auxiliary points are used.
It is composed of one. Line types are classified into three types: (i) straight line SL, (ii) broken line BL, and (iii) arc CL. There are auxiliary points ▲ P ^BL _{i, j} ▼ and ▲ P ^CL _{i, j} ▼ at the broken line BL and the circular arc CL. This feature parameter is unnecessary if the stroke division is set to be considerably larger than five equal parts (for example, 20 divisions), because the trace coordinate calculation can be approximated by a straight line. However, since the size of the dictionary is large, generally 3-5 equal parts are used, and thus interpolation information of such strokes is necessary for smooth trace display. FIG. 7 shows an example of characteristic parameters of only the second image in FIG. In this example, there is no line type for the arc CL,
It is composed of a straight line SL and a broken line BL. Note that the above dictionary pattern shows a case where the dictionary pattern is shared with a dictionary for unknown pattern recognition and a dictionary for trace display, but these may be separate dictionaries. The configuration and schematic operation of the first embodiment of the present invention have been described above. Next, a detailed embodiment of the first blocks 5, 6, and 7 will be described with reference to FIGS. . The above block can be realized by software of a microprocessor (not shown). FIG. 8 shows the flow of the main program. First, in step 100, trace display characters are selected and designated by a method as shown in FIG. Next, the leading address of the dictionary pattern 4 is calculated from the character selected in step 110, and the dictionary of the first stroke is first read from this address (step 120). Here steps 120-210
The processing loop processes all the strokes of the specified character. On the other hand, steps 130 to 180 process all five equal parts obtained by dividing the stroke into five equal parts for the i-stroke. That is, in step 130, the characteristic parameters of the j lines are read, and in step 140, the line type is determined. If it is a straight line SL, the process jumps to step 150 to perform a process of calculating a straight line trace coordinate and displaying a trace. At the same time, if it is a broken line BL, the process jumps to step 160, and if it is an arc CL, it jumps to step 170, and the trace coordinate calculation and trace display are processed. When the trace display of one stroke is completed, the end mark EOM and the stroke sequence number SNO are displayed together with the trace display as shown in FIG. 3 (step 19).
0,200). The display processing of the EOM and SNO may be performed after the processing in step 120 is completed, and may be performed before the trace display. When all of the above processing is performed on the stroke, the result is displayed as shown in FIG. 3 (b). When the end mark (EOM) of step 190 is changed to the start mark SOM, the display can be made as shown in FIG. 4 (b). Next, in the processing flow of FIG. 8, details of the processing of steps 150 to 170 are shown in FIGS. 4 to 11. FIG. 9 is a detailed flow chart of calculating the trace coordinates of a straight line and displaying a trace. First, both ends coordinates P _i of the j line segment i stroke at step _{150-a, j (X i} , j Y i, j), P i, j + 1
_{(X i, j + 1,} Y i, j + 1) leading from the dictionary pattern. Next, the straight line equation passing between the above two points is described in step 150.
Determined by −b. That is, the time of the linear process is represented by the time (1). The trace coordinates are calculated from the equation (1), and the trace is displayed on the display device (step 150-c). Next, after a delay of a predetermined time (delay), the same trace display is performed, and the trace display for j lines is completed (step 150).
-D, 150-e). FIG. 10 is a detailed flow of calculating the trace coordinates of a broken line and displaying a trace. First, the coordinates of three points necessary to fold line display at step 160-a, _{i.e., P i, j (X i} , j Y i, j), ▲ P BL i, j ▼, (▲ X
_{^{BL i, j ▼, ▲ Y}} BL i, j ▼), P i, j + 1 (X i, j + 1, Y
_{i, j} + ₁ ) is read from the dictionary pattern. Next, it is determined by the two linear equations (2) and (3) in step 160-b. That is, Is represented by The following processing steps 160-c to 160-e are the same processing as steps 150-c to 150-e in FIG. FIG. 11 is a detailed flow chart of calculating the trace coordinates of an arc and displaying the trace. Similar to FIGS. 9 and 10, first, the coordinates of three points required for the arc tracing, that is, P _{i, j} (X _{i, j} , Y _{i, j} ), ▲ P ^CL
_{i, j ▼, (▲ X} CL i, j ▼ ▲ Y CL i, j ▼), P i, j + 1 (X i, j
_{+ 1, Y i, j +} 1) leading from the dictionary pattern. next,
A circular equation passing through three points is obtained in step 170-b. That is, Is represented by The following processing steps 170-c to 170-e are the same processing as steps 150-c to 150-e in FIG. Although this processing is performed by arc approximation, this processing may be used as an equation of a spline curve passing through three points. As described above, in one embodiment of the first invention of the present invention, since the dictionary pattern is composed of the feature point coordinates and the feature parameters for interpolating the feature point coordinates, even if the dictionary size is small, the trace display of the strokes is relatively easy. The effect is obtained smoothly. Further, since the trace display of the character pattern is sequentially displayed to the user, and the sequence number of the stroke and the input direction of the stroke are also displayed, the input procedure of the registered character pattern can be grasped intuitively. Next, another embodiment of the first invention of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. FIG. 12 is compared with FIG. 3, a modification of the display method of the trace, as in the Fig. 12 (a), sets the display mode M _D traces singlet (M _D = 1), temporarily displaying fast trace a character pattern, then, sets the display mode M _D to double line (M _D = 2), it is an example of velocity trace display can be grasped by the user. In this way, since the guideline of the registered character pattern can be grasped, it is possible to appeal more intuitively. FIG. 13 shows a program for realizing this display method.
The difference from the flow in FIG. 8 is that steps 250 to 2 in FIG.
70 and the processing of steps 300 to 310. That is, the steps
In order to perform high-speed and low-speed trace display at 330 and 310, all trace coordinates of the character pattern are calculated at steps 250 to 270 and stored in a buffer. Accordingly, the high-speed and low-speed trace displays of steps 300 and 310 are performed while reading the buffer contents stored as described above, as shown in FIG. 14 and FIG. As described above, the example of the display mode has been described from the single solid line to the double solid line, but the solid single line may be changed to a dotted line, or the line color may be changed. On the other hand, although not shown, the position of the high-speed trace display and the position of the low-speed trace display may not be the same and may be displayed separately. Next, an embodiment of the second invention as the present invention will be described with reference to FIGS.
This will be further described with reference to the drawings. FIG. 16 is a block diagram of an embodiment of the second invention of the present invention, which is characterized by displaying a mark indicating a stroke input method as a teaching method of an input procedure. Therefore, as compared with FIG. 1, by using the coordinate information of the tablet 1, the operator selects the character whose input procedure is to be taught by the character selecting means 5A, from the dictionary pattern 4 of the character selected by the character selecting means 5A. A mark display means 7A for displaying a mark indicating the input direction of the stroke at one of the start / end point coordinates detected by the start / end point detection means 6A, 6A which detects the start / end point coordinates of each stroke, or an intermediate point coordinate position thereof. Is done. The blocks 1 to 4, 5A, and 8 operate in the same manner as in FIG. FIG. 17 is a processing flow for realizing the blocks 5A, 6A, and 7A of FIG. As the mark display, as shown in FIG. 3 (b) (however, a dynamic display mode as shown in FIG. 3 (a) is not included), an arrow mark and an end point coordinate position of each stroke are displayed. Stroke sequence number (SN
O) is displayed. The start and end point coordinates can be easily detected from the dictionary pattern feature point coordinates (P _{i1 to} P _i6 ) shown in FIG. That is, the start point coordinates are P _i1 and the end point coordinates are P _i6 . In FIG. 17, the end point coordinates are selected as the mark display position. However, in another embodiment, the end point coordinates may be set as the start point coordinates or an intermediate point (but not limited to the center) of the start and end point coordinates. As described above, in the embodiment of the second invention of the present invention, since the mark indicating the direction of the stroke is displayed, the input procedure cannot be dynamically displayed, but there is an effect that the input procedure can be statically taught. [Effects of the Invention] As described above, according to the present invention, it is possible to make the operator understand the stroke order by reducing the display speed of the registered character pattern.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an embodiment of the first invention of the present invention, FIGS. 2 to 4 are explanatory diagrams of the operation of the first embodiment, and FIGS. 7 is a diagram for explaining the configuration of the dictionary pattern of FIG. 1, FIGS. 8 to 11 are diagrams showing a processing flow of the software of FIG. 1, and FIGS. 12 to 15 are diagrams of another embodiment. FIG. 16 is an operation explanatory diagram and a flowchart of software processing, FIG. 16 is a block diagram of an embodiment of the second invention of the present invention, and FIG.
It is a figure which shows the processing flow of the software of the figure. 1 ... tablet, 2 ... handwriting stroke storage means, 3
…… Character recognition / dictionary creation means, 4 …… Dictionary pattern, 5
... Trace character selecting means 6, Trace coordinate calculating means 7, Trace display means 8, Display device, 5A
Character selection means, 6A ... start / end point detection means, 7A ... mark display means.

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Junko Mori               4026 Kuji-cho, Hitachi City, Ibaraki Prefecture Co., Ltd.               Hitachi Research Laboratory, Hitachi Research Laboratory (72) Inventor Toshimi Mifune               4026 Kuji-cho, Hitachi City, Ibaraki Prefecture Co., Ltd.               Hitachi Research Laboratory, Hitachi Research Laboratory (72) Inventor Toshio Takekoshi               1 Horiyamashita, Hadano-shi, Kanagawa               Hitachi, Ltd., Kanagawa Plant (72) Inventor Yoshiaki Konishi               1 Ikegami, Haruoka-cho, Owariasahi-shi, Aichi Pref.               Hitachi, Ltd. Asahi Plant                (56) References JP-A-62-212684 (JP, A)                 JP-A-61-295588 (JP, A)

Claims (1)

(57) [Claims] A tablet for inputting a handwritten stroke, a pattern storage unit in which a plurality of character patterns formed by a stroke composed of a plurality of coordinate point sequences are registered, and a character pattern registered in the pattern storage unit in the handwritten stroke. In a handwritten character recognition device having at least a recognition unit for comparing and recognizing and a display device for displaying the recognized result, a character pattern registered in the pattern storage unit is selected, and the selected character pattern is formed. A handwriting character recognition device, comprising: control means for displaying a plurality of sequences of coordinate points constituting the stroke with a predetermined time delay according to the stroke order when displaying the stroke to be performed in the stroke order. 2. In Claim 1, when displaying the stroke, the control means obtains a coordinate point that complements between coordinate points registered in the pattern storage unit, and determines the complemented coordinate point and the pattern storage. A handwritten character recognition apparatus characterized in that coordinate points registered in a section are displayed after being delayed for a predetermined time in accordance with the stroke order. 3. In Claim 1, the control means displays the character pattern stored in the pattern storage unit for each total number of strokes of the character pattern, and selects a character pattern based on an input from the tablet. A handwritten character recognition device, characterized in that: 4. A tablet for inputting a handwritten stroke, a pattern storage unit in which a plurality of character patterns formed by a stroke composed of a plurality of coordinate point sequences are registered, and a character pattern registered in the pattern storage unit in the handwritten stroke. In a handwritten character recognition device having at least a recognition unit for comparing and recognizing and a display device for displaying the recognized result, a character pattern registered in the pattern storage unit is selected, and the selected character pattern is formed. A handwriting character recognition device comprising control means for displaying a stroke to be performed at least two times at different display speeds in accordance with the stroke order. 5. 5. The handwritten character recognition device according to claim 4, wherein the control means displays a character pattern to be displayed later at a display speed lower than a display speed of the character pattern displayed earlier. 6. In claim 4 or 5, wherein the control means, when displaying a stroke constituting the character pattern, sequentially displays a plurality of coordinate points constituting the stroke in a stroke order. Handwritten character recognition device. 7. 7. The handwritten character recognition device according to claim 4, wherein the control means displays character patterns having different display speeds at different positions. 8. 8. The handwritten character recognition device according to claim 4, wherein the control means displays character patterns having different display speeds in different colors. 9. In Claim 4, when displaying said stroke, said control means calculates | requires the coordinate point which complements between the coordinate points registered in said pattern storage part, and this said coordinate point and said pattern storage A handwritten character recognition apparatus characterized in that coordinate points registered in a section are displayed after being delayed for a predetermined time in accordance with the stroke order.