JPH03135560A - Trimming device of scanner - Google Patents

Abstract

PURPOSE:To obtain a decomposed image which is directly trimmed by a scanner by displaying an image signal, which is read by prescanning and stored, on a monitor, specifying a trimming range for the displayed image, and calculating the read range of an image read means according to the specified trimming range. CONSTITUTION:The image read means 3 prescans a document F in a specific range, the read image signal is stored in an image memory 19 temporarily, and then the image signal is read out of the image memory 19 and displayed on the monitor 20. A coordinate specifying means 21 specifies the trimming range for the displayed image. Then the read range of the image read means 3 is calculated according to the data from the coordinate specifying means 21 and the document F is scanned by the read means 3 according to the arithmetic result to obtain the color-decomposed image which is already trimmed. Consequently, the color-decomposed image which is already trimmed can be obtained directly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plate-making scanner capable of trimming an original image during exposure.

In order to print a color original image, it is necessary to create multiple separation plates for each specific color of the original image, such as Class 311 or four types of separation plates. So-called color separation scanners have been used in the past.

However, with conventional scanners, it is difficult to arbitrarily select only a predetermined portion of the set original image and read and expose the image signal. Create a mask version for trimming separately from the disassembled version that will be used,
Conventionally, a method of trimming from a disassembled plate has been adopted, and therefore, there has conventionally been a problem in that time and cost are required to create a mask plate for trimming.

SUMMARY OF THE INVENTION An object of the present invention is to provide a scanner trimming device that eliminates the above-mentioned problems of the conventional technique and allows a scanner to immediately obtain a disassembled plate arbitrarily trimmed.

In order to achieve this object, the present invention stores image signals read from the original image in advance, and specifies the scanning position of the original image on the monitor image plane based on the image signals read from the original image.

It is characterized in that only a portion corresponding to a predetermined portion of the original image is exposed by switching the image signal read according to the specified position 7 at the time of reading and exposing the original image.

Embodiments of a scanner trimming device according to the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, 1 is a reading scanning drum, 2 is an exposure scanning drum, 3 is a reading head, 4 is an exposure head, and 5 is a control. III device, 6 is a clock generation section, 7 is a drum drive section, 8 is a scanning head drive section, 9 is an image signal processing section, 10 is a film exposure section, 11 is a preamplifier, 12 is a sample hold circuit, 13 is an A/D (analog-to-digital converter), 14 is a bidirectional bus driver, 15 is a buffer memory, 16 is an address counter, 1
7 is address selector, 18 is l10 (input/output controller)
, 19 is an image memory, 20 is a monitor, 21 is a coordinate specifying device, 22 is a gate, and 23 and 24 are changeover switches. Note that F indicates the manuscript.

The scanning drums 1 and 2 are rotated at a constant speed by a drum driving section 7 at a predetermined synchronous speed.

The reading head 3 and the exposure head 4 are linearly driven by a scanning head drive section 8, and move intermittently or continuously at a predetermined speed in synchronization with the rotation of the scanning drum 1. The image signals are read from the original document F, which is being stored, and the image signals are exposed onto a film (not shown) wound around the scanning drum 2.

Controller! 5 is operated by a program incorporated as software or hardware, and has various data processing functions and control functions for other devices such as a clock generator 6.

The clock generator 6 operates according to instructions from the control device 5, and serves to generate a scanning head feeding clock C5 and a scanning sampling clock C5 having different frequencies depending on scanning conditions.

The image signal processing unit 9 receives the image signal S read by the reading head 3.
It functions to perform the necessary processing.

The film exposure section 10 operates the exposure head 4 to perform exposure using the image signal S or S.

Therefore, these scanning drones 1.2, head 34, control device 5, clock generator 6, drum drive section 7, scanning head drive section 8, image signal processing section 9, film exposure section 10
This scanner is the same as a normal color separation/shading scanner, and by switching the changeover switches 23 and 24 to the a-contact side, it operates as a normal scanner and can obtain the necessary separated plates.

Next, when the changeover switch 23 is switched to the contact side, the sample and hold circuit 12 samples the image signal S+ inputted from the image signal processing section 9 via the preamplifier 11 using the clock C1, and holds the image signal S+. D
It functions to supply 13.

The bidirectional bus driver 14 functions to input the output of the A/D R3 to the buffer memory 15 and to send data read from the A/D I3 to the control device 5.

The address counter 16 counts the clock C3, operates the address selector 17 based on the data, and specifies the address of the buffer memory 15.

Here, W is a signal that controls the buffer memory 15 to write data, and is generated during the image signal scanning period during one rotation of the scanning drums 1 and 2, and R2 specifies the data read address of the buffer memory 13. Therefore, during the scanning period, the buffer memory I5 stores the image signal S at a different address I for each sampling point. The data is inputted sequentially to the /s and stored for one scanning line, and the data is inputted to the control device 5 between the end of the scanning period and the beginning of the next scanning period.

The control device 5 converts the image data input from the buffer memory 15 into a collection of appropriate image data according to a preset document size and exposure magnification, and transfers it to the image memory 19 via l1018.

The monitor 20 functions to reproduce one frame of image data stored in the image memory 19 as a still image on an image projection surface.

The coordinate specifying device 21 is equipped with an operation input unit such as a keyboard and a joystick, and is operated by the control device 5 to move the position of a rectangular trimming mark of a preset size that is being reproduced on the image projection surface of the monitor 20 to an arbitrary position. ,
It functions to generate data Pxv representing the coordinates of a predetermined position.

The gate 22 operates in response to a gate signal GT from the control circuit 5, and gates the image signal S to generate a trimmed image signal S in which only a predetermined portion thereof is extracted.

It works to take out.

The changeover switches 23 and 24 change the operation of the scanner to the normal disassembly plate creation operation (both switches 23 and 24 are switched to the a contact side).

(2) Scanning before trimming (switch 23 to the b contact side. Note that the switch 24 may be on either contact side).

■Trimming plate creation operation (switch 23 to the a contact side,
Switch 24 is switched to the b contact side).

It functions to select one of the three modes, and may be operated manually or automatically by the control device 5.

Next, the operation of this embodiment will be explained.

First, the operation in mode ■ is the same as a normal scanner and has already been explained, so a detailed explanation will be omitted.

When creating a trimmed version of document F, it is necessary to first operate in mode (2), then perform necessary trimming operations, and then operate in mode (2).

Therefore, as shown in FIG. 2, first, attach the document F to the scanning drum 1, set a part with a larger area than the part F to be trimmed, and define it as the pre-scan part F0. .

Next, the mode is set to ■, the switch 23 is switched to the b contact side, and the scanning drum 1 is rotated and read.

Reading of the image signal S from the pre-scanned portion F7 of the document F is started by the feeding operation of the document F3. At this time, as shown in FIG. 3, the scanning line pitch L is determined by the feed pitch of the reading head 3, that is, the clock D, and the sampling pitch SP is determined by the clock C5.

At this time, in order to read the image signal S from only the pre-scanned portion F0 of the document F, the coordinates X, Y of the scanning start origin P0 on the surface of the scanning drum I must be adjusted.

It is necessary to detect this, but there is no problem because a normal scanner is equipped with an encoder or the like on the scanning drum 1, and the coordinate Y in the rotational direction can be easily determined.

Since the coordinate Xo in the X direction is determined by the position of the reading throat 3, either a linear position detector is provided on the reading throat 3, or a reference point whose position can be adjusted is provided in the feeding direction. The position of the reading gutter 3 at the reference point is detected by some means, such as a microsinch or a proximity switch, and then the clock D is counted to determine the position of the reading gutter 3 in the X direction, that is, the coordinate x0.
All you have to do is ask for it.

Thus, the scanning start origin P of the previous scanning portion F0.

Once this is determined, the scanning end position can also be determined in the same way, so that the pre-scanning portion F can be set arbitrarily.

As already explained, the image signal S from the previous scanning portion F0 is accumulated in the buffer memory 15 for each scanning line, and then sequentially transferred to the image memory 19 and stored therein.

As a result, when the reading scan from the entire area of the previous scanning portion F0 is completed, the image signal for one frame corresponding to this portion F0 will be stored, so the image of the previous scanning portion F0 will be displayed on the monitor 20. will be played.

Therefore, the operator operates the coordinate specifying device 21 to move the position of a rectangular trimming mark of a preset size that is being reproduced on the image projection surface of the monitor 20 together with the image of the previous scanning portion F0, and Match the image of F. As a result, V is input to the control device 5 as P representing the coordinates x, y of the origin P1 of this trimming portion F.

As a result, the control device 5 obtains the coordinate data x2 and Y of the origin P of the rimming portion Ft shown in FIG.

is calculated, and dy is stored in this and the trimming size d, respectively.

When the storage of these data Xa, Yy, d+c, and dy is completed, the control device 5 or the operator switches the operation to mode ■, and the switch 23 is closed to the a contact side and the switch 24 is closed to the b contact side. .

Then, an unexposed film is set on the scanning drum 2, and the operation of the scanner is started.

Next, the operation at this time will be explained with reference to the timing chart of FIG.

In FIG. 4, S is an image signal input from the image signal processing unit 9 to the gate 22 via the a contact of the switch 23 and the b contact of the switch 24, and G is the image signal input from the control device 5 to the gate 22. The gate signal S7 is a trimming image signal extracted from the gate signal G and the biased image signal S at the gate 22 and exposed to the exposure head 4 from the film exposure section 10, and L is the trimming image signal when the scanning drum 1 rotates once. represents the period of time.

The control device 5 monitors the coordinate Y due to the rotation of the scanning drum 1 and the coordinate X due to the position of the reading head 3, and further determines that the reading position by the reading head 3 is the origin P, based on the captured data Xr, Yr, dx, dy. A gate signal G having a pulse width TdV is generated at regular intervals from time t0 when t0 is reached, and this is continued during the period from time t0 to Tdx. Here, the pulse width Tdy is equal to the time required for the scanning drum l to rotate the distance of the trimming size dy in FIG. 2, and the period Tdx is equal to the time required for the recording head 3 to move the distance of the trimming size dx. equal. Since the control device 5 has all the rotational speed and rotational phase of the scanning drum 1, as well as the movement speed and position of the reading gutter 3, these and the above-mentioned data Xt, Yt.

The control device 5 can easily generate the gate signal G7 using dx and dy.

The gate 22 receives the image signal S by this gate signal Ga.
, and the extracted signal S7 is obtained as a trimmed image signal.As can be easily understood by comparing FIG. 2 and FIG. It can be seen that the image signal S7 is only the image signal when the trimmed portion FA of the original image F is scanned.

Therefore, if the trimmed image signal S extracted by this gate signal G7 is exposed to light by the gutter 4, only the trimmed portion F will be exposed to the color-separated exposure image C.
According to this embodiment, a rimming plate can be produced directly by a scanner.

Incidentally, in the above explanation, the frequencies of the clocks Ds and Cs in mode (2), that is, the scan before trimming, were not particularly explained, but these frequencies may be controlled arbitrarily.

Of these, the clock D determines the feed speed of the reading head 3, and can change the scanning line pitch shown in FIG. The time required to scan the entire portion F0 and store one frame worth of data in the image memory 19 can be shortened.

Further, the clock C8 determines the sampling points P of the image shown in FIG. 3, and the higher the frequency of the clock C8, the smaller the sampling pitch S, and the greater the number of sampling points P per scanning line.

Since the sampling point P, that is, the number of pixels in the entire pre-scanning portion F0 is determined by the scanning line pitch, and the sampling pitch S, the storage capacity required for the image memory 19 is determined by the frequency of the clocks D and C3. will be determined. Therefore, by increasing the frequency of the clock D and lowering the frequency of the clock C8, the storage capacity of the image memory 19 can be reduced.

On the other hand, in the above embodiment, the image signal obtained by the previous scan is reproduced on the monitor 20, and trimming is performed on the reproduced screen, so that if the pixel density of the reproduced image is coarse, the accuracy of trimming will be reduced.

Therefore, clock D. The frequencies of C3 and C3 may be set by taking into consideration the time required for pre-trimming scanning, the storage capacity required for the image memory 19, and the trimming accuracy.

For example, in the above example, locm x 8 cm
When scanning a document of (χ
This is within 0.1 ws, and in this case, sufficient accuracy can be obtained to determine the trimming range on the document.

However, under conditions where the exposure magnification is larger than this, the deviation of the trimming range on the exposed film will be large, so the number of scanning lines in the pre-scanning should be increased according to the exposure magnification, and the sampling pitch should be finer. So feed clock D. The frequency of the sampling clock C1 and the frequency of the sampling clock C1 may be adjusted by the control device 5.

Furthermore, since it is sufficient to use a black and white monitor 20 as a pre-scanning image display type display, if we consider a 512 x 512 pixel image memory to be used, each pixel has 8 gradations for the picture. Assuming that 3 bits are taken and 1 bit is taken for displaying the trimming mark, a total of 128 KB of image memory 19 may be used.

In the above embodiment, the buffer memory 15 is a single buffer memory, but if the target scanner is a high-speed scanner, the buffer memory 15 may be a double buffer to handle writing and reading of image data. You can do it in parallel.

Next, the effects of the present invention are listed below.

(a) According to the present invention, there is no need to create a mask plate when trimming the separated plates of a color original as in the conventional process, so the amount of mask film used in plate-making work is reduced, and the work is speeded up. It is also useful for

([+) In a computer layout scanner system equipped with a large magnetic disk device, if the trimming scanner according to the present invention is used for input, it is only necessary to hold the data of the trimmed image as the input image, and the amount of data to be held can be reduced. Since it freezes, magnetic disk packs can be used effectively.

(c) Compared to the case of performing trimming processing using a layout scanner system, the present invention allows trimming to be performed more easily and simply, and the system configuration does not require a large-scale system, so it is inexpensive. It has the advantage of being done.

(d) The pre-scanning method used in the present invention allows the functions of a normal scanner to be used as is, so there is no need for a special dedicated device for pre-scanning, and it can be replaced with a conventional scanner relatively easily. It is possible to incorporate a trimming mechanism.

As described above, according to the present invention, a trimmed disassembled plate can be obtained immediately by a scanner, thereby eliminating the drawbacks of the prior art and providing a scanner trimming device that requires less time and cost for trimming. can do.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of a trimming device for a scanner according to the present invention, FIGS. 42 and 3 are explanatory diagrams showing its operation, and FIG. 4 is a timing chart. 1.2--Scanning drum 3--Reading head exposure head 5-1--Control device 11-
-Preamplifier 12--m-sample hold circuit] 3----A/D (Analog-to-digital converter) 14-1111 Bidirectional bus driver 15--Banfer memory 16-- Address counter 17 --- Address selector I8 --- 110 (human output system? fi device) I9 --- Image memory 2o-- Monitor 21 --- One coordinate designation device ff 2 :" --- Gate 23.24. ---
- All changes, Figure 2 Figure 3 p Procedure t11 Masako (voluntary) June 29, 1990 rl

Claims (1)

[Claims] an image reading device for reading a predetermined range of an original image; a memory for storing an image signal of a pre-scanned portion of the original image read by the image reading device; a monitor for displaying the image, a coordinate position specifying means for specifying a trimming range of the original image with respect to the image displayed on the monitor, and a method for obtaining a trimmed input image based on data from the coordinate position specifying means. What is claimed is: 1. A scanner trimming device comprising: switching means for switching an image signal, and storage means for storing the trimmed input image.