JPS6146671A - Area designation system - Google Patents

Abstract

PURPOSE:To attain designation of optional area simply without giving dirt on an original with less memory capacity by reading in advance a sheet on which two diagonal apexes are described to designate an optional square area on the original so as to apply area designation. CONSTITUTION:At first, on the original 1 a transparent sheet 2 of the same size is overlapped and two diagonal points P1, P2 for discriminating a square area are marked on the transparent sheet 2 by using a proper mark pen. Then only the marked transparent sheet is read to the device to store coordinates of the two points P1, P2. When the original 1 is read by the device, the coordinates of the stored points P1, P2 are read, and a different picture processing is executed from the inside and the outside of the square area designated by the two points P1, P2.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an area specifying method for performing different image signal processing on a specified area and other areas of a document image read by a document reading device. [Prior Art] Conventionally, this type of area specification method includes: (1) A document is placed on a platen provided with a coordinate scale, and the coordinates of the four vertices of the specified area are specified using a numeric keypad.(2) Platen (3) In a reading device capable of distinguishing multiple colors, a boundary for specifying an area on a document using a specific color is used. There was a method for specifying an area by drawing a line and having the device determine the boundary line. [Problems to be Solved by the Invention] However, in the method (1) above, it is troublesome to accurately determine the coordinates of the vertex from the coordinate scale, and in the method (2) above, the lever slides on the platen. Since a mechanism for this is required, there is an inconvenience that the space on the platen becomes complicated. In addition, in method (3) above, since the border line is written directly on the document, if the document gets dirty and the border line overlaps the document image, accurate color separation may not be possible (or the document image itself There is a problem that the reading quality of the document is deteriorated. [Means for solving the problem] In the present invention, in order to specify an arbitrary rectangular area of the document, the sheet position corresponding to the rectangular area is set. For example, a transparent sheet for writing two diagonal vertices of the rectangular area, means for detecting the coordinates of the two vertices written on the sheet, and a memory for storing the coordinates of the two detected vertices. and means for reading out the coordinates of the two vertices stored in the memory when reading the original, thereby performing different image signal processing inside and outside a rectangular area specified by the two vertices. [Operation] Original Before starting to read the sheet, each coordinate of the two diagonal vertices is stored in the memory by reading the sheet on which the two diagonal vertices are written, and after that, when reading the document, each coordinate of the two vertices stored in the memory is stored in the memory. The specified rectangular area is identified by reading out the square area, and different tI filter image signal processing is performed inside and outside the rectangular area specified by the two vertices by kneading. In the embodiment, as shown in FIG. 2(a), a transparent sheet 2 of the same size is superimposed on the document to be read, and two points P1 and P1 are placed on the transparent sheet 2 to determine the designated rectangular area. Mark P2 using an appropriate marking tool. After this, mark the two points P1 and P2 as shown in Figure 2(b).
The device first reads only the transparent sheet 2 on which is written, but the device recognizes the 21 points P1 and P2 as two diagonal vertices of a rectangular area, and reads the 21 points P1 and P2.
Determine a rectangular area uniquely determined by points. The coordinates of the two points P and P2 are stored in the device, and when the document 1 shown in FIG. , the two points P, and different image processing is performed inside and outside the rectangular area specified by P2. In the example shown in FIG. 2, only the portion of the letter "E" undergoes image processing that is different from that of the other portions. Next, FIG. 1 shows an example of a device configuration for realizing the above-described effect. This device is a digital copying machine that is capable of partially erasing only the image of an original document area corresponding to a rectangular area specified by a transparent sheet 2. In FIG. 1, the light emitted from the light source 3 is transmitted to the platen 4.
- The reflected light is irradiated onto the original document 1 or the transparent sheet 2, and the reflected light is input to the image sensor 7 via the mirror 5 and lens 6. The image sensor 7 is a line sensor composed of a solid-state image pickup device such as a CCD type, and converts an optical signal corresponding to each input pixel into an electrical signal. The output of the image sensor 7 is input to an A converter 8, where it is converted into 1-bit binary data of black or white. The output of the A/D converter 8 is input to a shift register 9 and an AND circuit 10. The shift register 9 is a serial input/parallel output type composed of a predetermined number of seven lip-flops, and all of the parallel outputs are input to an AND circuit 11. The configuration of the shift register 9 and the AND circuit 11 allows points written on the transparent sheet 2 to be distinguished from noise, dust, and the like. That is, the output of the AND circuit 11 is sent to the shift register 9.
Logic level ``1'' is not output unless all the parallel outputs of the logic level ``11'' are reached. " signal is output. The output of AND circuit 1 is applied to one input terminal of AND circuit 12 and to inhibit circuit 13. The output of the inhibit circuit 13 is applied to the other input terminal of the AND circuit 12 via an inverter 14. The inhibit circuit 13 is inputted with a line clock signal φ1 that outputs one pulse each time the main scanning line advances by one.
When the inhibit circuit 13 receives a signal of logic level "1" from the AND circuit 11, it starts counting the line clock signal φ1 after the input, and also receives the first line clock signal φ. At that point, the output is raised to logic level "1". The output of the logic level "1" is held until the count value of the signal φ reaches a predetermined value, and therefore the output of the AND circuit 11 is changed to the -H logic level by the output of the inhibit circuit 13 via the inverter 14. The signal is inhibited for a predetermined number of lines from the start of scanning of the next line after outputting the signal "1". This is to prevent the same point from being detected multiple times with different coordinates. Next, the output of the AND circuit 12 is input to the clock terminal CP of the flip-flop 15. The flip-flop 15 has a toggle type configuration, and has a clock terminal CP.
Whenever a signal of logic level "1" is input to the output Q
, Q are respectively inverted, so-called binary operation is performed. That is, when the first designated point P is detected by the above-described configuration, the output Q of the flip-flop 15 becomes "1" and Q is "0", and when the second designated point P is detected, "Q is 10" and Q is "1" are input to the terminals. Next, a video clock φ synchronized with the reading of each pixel is input to the main scanning address counter 20. 20 outputs an address in the main scanning direction to the start address register 16 and the end address register 18 by cyclically performing a +1 power count operation for the number of pixels of one main scanning line in synchronization with the video clock φ. The sub-scanning address counter 21 has a line clock φ1.
is input, and the sub-scanning address counter 21 outputs an address in the sub-scanning direction to the start address register 17 and the end address register 19 by performing a +1 count operation in synchronization with the line clock φ. That is, the start address registers 16 and 17 receive the count outputs of the main scanning address counter 20 and the sub-scanning address counter 21 when the Q output of the flip-flop 15 rises, thereby starting the first address register.
The end address registers 18 and 19 capture the count outputs of the main scanning address counter 20 and the sub scanning address counter 21 when the Q output of the flip-flop 15 rises. Store the coordinates of the second designated point. Next, multiplexer 22 selects either start address register 16 or end address register 18 based on the output of flip-flop 26 and outputs it to comparator 24 . In this case flip-flop 26
When the output of the start address register 16 is "0",
selects the output of the flip-flop 26, and the output of the flip-flop 26 is "1".
Suppose that the output of the end address register 18 is selected when . Similarly, multiplexer 23 selects either start address register 17 or end address register 18 based on the output of flip-flop 27 and outputs it to comparator 25 . The comparator 24 compares the output of the multiplexer 22 and the output of the main scanning address counter 20, and outputs "1" when the comparison outputs match.
5 also compares the output of the multiplexer 23 and the output of the sub-scanning address counter 21, and outputs "1" when the comparison outputs match. Flip-flops 26 and 27 perform binary operations based on the outputs of comparators 24 and 25, respectively;
When the first "1" output is inputted, the output signal rises to "11" and when the second "1" output is inputted, the output signal falls to "0". That is, the area in the main scanning direction is identified by the configuration of the multiplexer 22, comparator 24, and flip-flop 26, and the area in the sub-scanning direction is identified by the configuration of the multiplexer 23, comparator 25, and flip-flop 27. The outputs of flip-flops 26 and 27 are NAND circuit 2
8, and the output of the NAND circuit 28 is input to the AND circuit 10.
A/l) After being ANDed with the output of converter 8,
Output. In such a configuration example, the operator first starts by referring to FIG.
), the transparent sheet 2 is placed on top of the original 1, and two diagonal vertices P0 and P for identifying a predetermined rectangular area are appropriately written on the transparent sheet 2. Next, as shown in FIG. 2(b), only the transparent sheet 2 on which the two vertices P1, P, and 2 are written is placed at a predetermined position on the platen 4, and reading of the transparent sheet 2 is started. do. The image on the transparent sheet 2 is read by an image sensor 7, converted into black or white binary data by an A/l) converter 8, and sequentially input to a shift register 9. After that, the data corresponding to the first specified point P is input to the shift register 9, and when all the parallel outputs of the shift register 9 become "1", the output of the AND circuit 11 becomes "11", and the AND circuit 11 becomes "11". The Q output of the flip-flop 15 rises via the circuit 12. As a result, the count outputs of the main scanning address counter 20 and the sub-scanning address counter 21 at this point are taken into the start address registers 16 and 17, respectively. After that, even if the output of the AND circuit 11 becomes "1" again during reading of a predetermined number of lines, the output is inhibited by the inhibit circuit 13, so that the point P
1, the 71J block flop 15 will not operate again. Similarly, the second specified point P2 is detected by the shift register 9 and the AND circuit 11, and the Q output of the flip-flop 15 rises at the detection point, thereby increasing the main scanning address counter 20 and the sub-scanning address at the detection point. Each count output of the counter 21 is taken into the end address registers 18 and 19, respectively.

[Remembered. In addition, when reading the transparent sheet 2, the AND Kate 10, the multiplexer 22, 23, the comparator 24
, 25 and flip-flops 26 and 27 are inactive, so as not to adversely affect the determination process of the specified points P1 and P. Next, the operator places the original 1 shown in FIG. 2(C) on the platen 4 and operates the apparatus to erase the image corresponding to the area specified on the transparent sheet 2. During this process, the flip-flop 15 outputs a clear signal CL.
It is cleared by H, and the output Q or Q of the flip-flop 15 does not operate the start address register 16 and ]7 and the end address registers 18 and 19 to update the stored contents. The image of the original 1 is read by the image sensor 7, and
After being converted into binary data by a 10 converter 8, the data is sequentially output to an AND circuit 10. First, focusing only on the main scanning direction, since the output of the flip-flop 26 is "0" in the initial state, the multiplexer 22 initially outputs the start address register 16.
The main scanning direction address of the first designated point P stored in is selected, and the selected address is added to the comparator 24. The comparator 24 compares the main scanning direction address of the first specified point P with the main scanning address counter 200 count output, and outputs "1" when these two reach -, thereby changing the output of the flip-flop 26. Raise it to "1". As the output of the flip-flop 26 rises, the multiplexer 22 switches the input, and this time the input is changed to the second specified point P stored in the end address register 18.
The main scanning direction address is added to the comparator 24. The comparator 24 compares the main scanning direction address of the second specified point P with the count output of the main scanning address counter 20 in the same manner as described above, and when they match, it returns to "
By outputting ``1'', the output of the flip-flop 26, which maintains the ``1'' state, falls to ``0''. As a result, the multiplexer 22 selects the start address register 16 side again, and thereafter, such an operation is repeated every time each main scanning line is read. In other words, the flip-flop 26 outputs a signal that becomes "11" when the document area indicated by the hatching on the lower left in FIG. 3 is read, and becomes "0" in other areas.
The area in the main scanning direction specified by the specified points P1 and P can be distinguished. Next, the specified area in the sub-scanning direction is determined.
According to the structure of the flip-flop 27, the discrimination process is performed in the same manner as described above, and the flip-flop 27 reads "1" when the document area indicated by the downward hatching in FIG. ” is output, and the area in the sub-scanning direction specified by the specified points P1 and P2 can be distinguished. The outputs of the flip 70 knobs 26 and 27 are input to the NAND circuit 28, so that the NAND circuit 28 outputs a signal of logic level "1" outside the area shown by crosshatching in FIG. , a signal of logic level "0" is output in the area shown by cross hatching. Therefore, when the image of the document 1 is read, the output of the AND circuit 10 is all "o" in the area shown by crosshatching in FIG. The area that was created will be erased. As described above, according to this embodiment, the operator overlays the transparent sheet 2 on the original 1, writes two predetermined diagonal vertices on the transparent sheet 2, and then writes the two diagonal vertices on the transparent sheet 2 before starting to read the original.
By simply having the device read the transparent sheet 2 on which the vertices have been written, it is possible to specify an area when reading a document, making it possible to easily specify an area without smearing the document with a small memory capacity. Become. In the above embodiment, the image in the specified document area is erased, but the image signal processing to which the present invention can be applied is not limited to this. For example, the image signal processing in the specified area may be extracted. Furthermore, the number of gradations for halftone reproduction, the enlargement rate, the reduction rate, the filter coefficient used for MTF correction, the threshold level of digital processing, etc. may be made different between the specified area and other areas. Furthermore, in the above embodiment, one set of diagonal points is written on the transparent sheet 2 to designate only one rectangular area, but by writing multiple sets of diagonal points, multiple square areas can be specified. The device may be configured so that different rectangular areas can be specified. In this case, start address register 1
6.17 and end address registers 18 and 19
For example, the first detected point and the second
The rectangular area formed by the third detected point is defined as the first area, and the area formed by the third detected point and the fourth detected point is defined as the second area, etc.・
It is easy to realize this by doing... Furthermore, although it is of course practical to use a transparent sheet as the sheet used in the present invention, an opaque sheet on which an appropriate coordinate scale is printed in advance is used, and diagonal corners of a rectangular area are printed on the coordinate scale. Two vertices may be entered. [Effects of the Invention] As explained above, according to the present invention, the area is specified by having the device read in advance a sheet on which two diagonal vertices for specifying a rectangular area are written. Therefore, it becomes possible to easily specify an arbitrary rectangular area with a small memory capacity and without staining the original.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIGS. 2 and 3 are diagrams for explaining aspects of the embodiment of the invention, respectively. 1... Original, 2... Transparent sheet, 3... Light source, 4
...Platen, 5...Mirror, 6...Lens, 7
...Image sensor, 8...A/1) converter, 9.
...Shift register, 10.11.12...AND circuit, 13...Inhibit circuit, 14...Inverter, 15,26,27...Flip-flop, 1
6.17...Start address register, 18.19
...End address register, 20...Main scanning address counter, 21...Sub-scanning address counter, 2
2.23... Multiplexer, 24.25... Comparator, 28... NAND circuit. Figure 2 Figure 3 (b) (C)

Claims (1)

[Claims] Before starting to read the original, each coordinate of the two diagonal vertices of a predetermined rectangular area is stored in a predetermined memory by reading a sheet in which two diagonal vertices of a predetermined rectangular area are written. An area specifying method characterized in that by reading the coordinates of the two vertices stored in a memory, the read data of the original is processed separately inside and outside the specified rectangular area.