JPS5960440A - Trimming scanner - Google Patents

Abstract

PURPOSE:To obtain a trimmed picture easily at low cost in a short time by using a cylindrical surface picture reading means capable of reading a picture- element data simultaneously out of a specific range of an original picture for a rotary drum type scanner. CONSTITUTION:The rotary drum type scanner which performs the reading and exposure of an original picture is provided with a cylindrical surface picture reading means 12 which photographs a picture at a part in a specific region of a read scanning drum 1 simultaneously, a memory 20 stored with those obtained picture data, a monitor 21, and a specified means 22 which specifies the scanning range of the original picture over a loop at the monitor. Then, picture data are switched during read exposure by a gate signal, so the need for the generation of a mask plate is eliminated and the capacity of the memory may be small, so a large-scale system is unnecessary, thus obtaining the scanner which obtains trimmed pictures at low cost in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color separation scanner for use in printing plates, etc., which enables trimming of original images during exposure.

In order to print a color original image, it is necessary to create multiple separated versions of the original image for each specific color, such as 3 Yanagi or Vi4 Yanagi. 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 expose the image signal. Create a mask version for trimming separately from the minute angle A version that is created,
Conventionally, a method of trimming from a disassembled plate has been adopted, and therefore, there has conventionally been a problem that time and cost are required to prepare a mask plate for trimming.

So, in order to solve this problem, in conventional scanners, the original image is roughened in advance before optical scanning (pre-scanning and reading the image signal 1) This reproduces the image for trimming. 1. Determine the trimming range on this reproduced image surface, generate the necessary gate signal, and gate the image signal read during reading fog light scanning to directly perform trimmed exposure, so-called A cropping scanner has been proposed.

However, in the trimming scanner that has been proposed in the past, the reading of image signals by the above-mentioned pre-scanning is performed by rotating the reading scanning drum and moving the reading scanning head, using the scanner's functions as is. This is done by the rotation of the CCD line sensor and reading scanning drum.
All of these methods involve the movement of a mechanical part such as the rotation of a reading scanning drum, and have the disadvantage that it takes a considerable amount of time to read an image signal in one previous scan, and furthermore, the trimming operation also requires a long time.

An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to read out image signals by pre-scanning required prior to reading exposure scanning without requiring any movement of mechanical parts, thereby completing trimming work in a short time. The purpose of the present invention is to provide a trimming scanner that can perform the following tasks.

In order to achieve this object, the present invention uses a cylindrical surface image reading means capable of simultaneously reading pixel data from a predetermined range of an original image having a cylindrical surface shape. It is characterized by the fact that it has been designed to

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

FIG. 1 shows an embodiment of a trimming scanner according to 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 jilil
+ control device, 6 is the drum drive section, 7 is the rm image signal processing section,
8 is a film exposure section, 9 is a rotary encoder, 10
1 is a linear encoder, 11 is a light source lamp, 12 is an image reading section, 13 is a light guide@6 14 is a photoelectric conversion section, 15 is a data selector, 16 is an analog/digital hair changer (A/D
,! : 17 is a bus driver, 18 it buffer memory, 19 is a human output controller (called Ilo), 2o
ilt image memory, 21 a monitor, 22 a seat rod designation device, and 23 a gate. Note that F indicates the original image to be trimmed.

The reading scanning drum 1 and the light scanning drum 2 remain stopped for 1 unit during image reading for trimming (hereinafter referred to as pre-scanning), which will be described later, and during reading exposure (hereinafter referred to as main scanning). ) is rotated at a constant speed by a drum driving section 6 at a predetermined synchronous speed.

The reading head 3 and the optical head 4Vi are held by a head drive mechanism (not shown), and are moved intermittently at a predetermined period or at a predetermined speed in the direction of the arrow in the figure in synchronization with the rotation of the drums 1 and 2 during main scanning. It moves continuously and scans the surfaces of the drums 1 and 2. - At this time, read head 3 reads the original image F.
The image signal S read from the image signal processing unit (also called a color computer) 1 undergoes predetermined processing to become an image signal 8S, and a predetermined portion is extracted by a gate 23 to produce a trimmed image (!!Tsukuda). ST, the film is supplied to the film exposure section 8, and the optical head 4 exposes an image to an unexposed film (not shown) held on the drum 2, and the color-separated film for plate making is supplied to the film exposure section 8. An exposed film is obtained.Therefore, the operation during this main scanning is the same as that of a normal scanner when the gate 23 is open.

The rotary encoder 9 serves to detect the 1u1 rotation angle position of the drum 1 and to supply a tM signal py representing it to the rblJ controller 5.

The linear encoder 10 detects the read head 30 position 1rf and supplies a negative signal PX representing it to the control device 5.

The image reading unit 12 and the light guide unit 13 convert the light from the lamp 11 that has passed through the original image F held on the surface of the drum 1 into
Each point of the original picture F is taken out independently, and the original -
The image of F is decomposed into each pixel and the light of each pixel is guided to the photoelectric conversion unit 14 (using a moving device such as multiple optical fibers as shown in FIGS. 2(a) and 2(b)). The optical waveguide 12a is composed of an optical waveguide 12a, and its optical input end 12b
They are arranged in a curved shape according to the surface shape of the fl drum 1. During pre-scanning, the light incident end 12b is the original ii! 'IIF is constructed so that it can be brought into close contact with the surface of the IIF.

The photoelectric converter 141 is attached to the opposite end of the light input end 12b of the optical waveguide 12a constituting the image reading unit 12 and the light guide unit 13, that is, the light exit end,
Convert the light passing through each optical waveguide 12a into an electrical signal! The data selector 15 is composed of photoelectric conversion elements with the number of axes consisting of photodiodes, etc. for converting
Sequentially selecting and taking out conversion elements according to a predetermined order 9
I'm going to do XIJ.

The bus driver 1T selects each ii! selected by the data selector 15! The signal 8p for each JI purple is digitized and received by the A/D 16, and it is sequentially stored in the / The image memory 20 serves to read and transfer the ii! from the buffer memory 18 to the control device 5. II image data was stored sequentially and read from the entire original 1jF by pre-scanning.
Functions to store image data.

The monitor 21 uses the image data stored in the image memory 2G to display original images! ] Functions to play back the IF image.

The coordinate specifying device 22 is equipped with a manual operation mechanism such as a keyboard switch and a joystick, and can arbitrarily specify the position of a rectangular trimming mark of a preset size that is being reproduced on the image projection surface of the monitor 21 by means of a control device 5. It functions to generate the PXY to be moved.

Gate 23 consists of the gate turtle mouth of Oil 1 Image No. 88] Ω Shina analog gate,! The Li control device operates in response to the gate signal GT which gives a control force value of 5, and II! I+ image (a trimming of a part of No. 3 Ss extracted at a predetermined timing.

It is recommended to generate an image signal i9T.

1 yo otsuta 1tiil? The IIl device VELs operate as software or 1-domains of our block rams.
It is configured to have a 1fA function and a control function for other devices 31.

Next, the operation of this embodiment will be explained.

This embodiment is based on the above-mentioned first trimming scan and subsequent trimming operation.
It operates in the main scanning 6-magnitude mode that captures 3 lights in the fc image.
Set the image F on the drum 1, place the image reading unit 12 on the drum 1, and start scanning 01.

As already explained, the image reading section 12 is connected to the river Li[! II
When placed in close contact with F, the light source lamp 11 power) Rahara ii! II
Each ti of k1! The light that has passed through the II element is independently sent to the photoelectric conversion section 14 through the optical waveguide 12a, where it is converted into a signal for each pixel. Then, the signals for each pixel are sequentially selected and extracted by the data selector 15 to become the image signal SP, converted to digital data by the A/D 16, and collected into the buffer memory 18 as a predetermined number of lII element data. The images are stored in the image memory 20.

At this time, the image reading unit 12 reads the original music IF, and the original [i! This is done simultaneously over the entire surface of the iiF, and the time required to transfer all the image data from the photoelectric conversion unit 14 to the image memory 20 is also the same as the time required for selecting and extracting each pixel by the data selector 15 and the time taken by the A/D 16. The conversion time is limited to the time required to store the data in the buffer memory 18 and transfer the data to the image memory 20, and since there is no need for any other rotational operation of the drum 1, the conversion can be carried out in an extremely short time.

Therefore, the pre-scanning is completed in a very short time after setting the original image F and setting the image reading unit 12, and
0 is the @image read from the original image F.

Now, in this Fig. 3, the point Po is the drum 1
This point P is shifted from the pre-trimming scan start point. A coordinate system can be defined in which the origin is x, the position along the axial direction of the drum 1, and y is the position along the circumferential direction, and the number of optical waveguides 112a arranged in the X direction is N. , the number of pixels arranged in the X direction is M, and if the X direction is the line scanning direction and the X direction is the surface scanning direction, then the number of pixels per one scanning line is N and the number of scanning lines is M. This becomes the image data of the book. Therefore, the position of arbitrary pixel data on one image plane read in the pre-trimming scan can be expressed by combining the scan line number 1 and the pixel number J within each scan line, as shown in FIG. Among them, the number I is located at position 1i (in the plane scanning direction of the optical waveguide), and the number J is located at an arbitrary position in the line scanning direction of the optical waveguide, respectively.

Now, when the pre-trimming scan is completed in this way, the next step is to proceed to the trimming operation, and the control device 5 uses the image memory 20
Based on the data read from the monitor 21, an image of the original picture F and trimming marks of a preset size are displayed on the monitor 21.

Next, the coordinate specifying device 22 is operated by the operator to move the trimming mark on the image projection surface of the monitor 21 in accordance with the position signal PXY, and perform trimming on the image surface of the original image F obtained by rJiJ yn scanning.
An appropriate trimming range is specified. This designation is input to the control device 5 by, for example, an operator's designation completion operation.

Therefore, the control device 5 learns the line number m and pixel number Jn of the reference point PT in the trimming range from the position signal PXY input at that time, and then determines the coordinate value xT in the coordinate system shown in FIG.

Calculate and memorize YT.

When the calculation of this reference point PT (xT#yT) is completed, the control device 5 switches to main scanning, and after an unexposed film (not shown) is attached to the scanning drum 2, the drum drive section 6 is sent to perform an erase scan. The drums 1 and 2 are driven to rotate at a constant speed,
The image signal 8b' from the reading head 3 - the H image m processing circuit γ is supplied to the film exposure section 8 via the gate 27, and the exposure of the e-trimmed image to the exposure head 4 is started. The operation will be explained below.

First, for explanation purposes, as shown in FIG. 4, an appropriate origin Do is taken on the surface of the scanning drum 10, and X is the feeding direction of the reading head 3, and Y is the direction opposite to the rotational direction of the scanning drum 10, that is, the surface scanning direction. A coordinate string is defined as 1, and the position of the scanning point on the surface of the scanning drum 10 can be displayed using the XY ridge.

Then, the X and Y coordinates of this scanning point can be immediately detected using the position signal PX obtained from the nya enhancer 10 and the position signal PY from the rotary enhancer 9, and the reference point PT for trimming scanning can be detected immediately. It is possible to calculate.

However, since the relative position 1h of the image reading unit 12Vi in the axial direction of the scanning drum 1 is often identified, the origin Do of the scanning drum 1 and the origin Po during the previous scan may not match. Therefore, the origin P is shown in Figure 4. is an offset (X o , Y
o). Therefore, the coordinates (XT, YT) at the trimming reference point PO)XY\M standard thread are expressed by: Therefore, at the time of pre-trimming scanning, the position coordinates (Xo, Yo
) is obtained from the position signals Px and PY and stored in the control device 5, the reference point PT can be easily calculated using the equation (1).

Therefore, when the control device 5 starts main scanning, it detects the reference point PT and generates a gate signal GT.
is operated at a predetermined timing, a portion of the image signal Ss is taken, a trimmed image (No. 4 ST) is extracted, and the exposure head 4 exposes it to an unexposed film, and the trimmed separated version is immediately generated. The operation at this time will be explained with reference to the timing charts of FIGS. 4 and 5.

In Fig. 4, the scanned portion of the original image F before trimming is
,)! The range designated by the J trimming mark, that is, the trimming part, is FT, and the trimming size is dx, d.
Let it be y. 1 original image F is the scanned part Fo before trimming
Assume that there is no pattern except for the area.

Then, the l1iII image signal 88 obtained by main scanning this has a waveform as shown in FIG. 5, for example. In this figure, L is the period required for one rotation of the scanning drum,
That is, it is one scanning line period.

In this state, when the control device 5 detects the reference point PT as described above, the scanning point is at a distance #l from that time to!
A pulse with a width equal to the time Tdy required to move by dy is generated every scanning line period full L, and is used as the gate signal GT. It is repeated for a time equal to the time Tdx to move by.

As a result, each time a pulse of the 23Vi gate signal GT appears, it turns on and passes the image signal Ss, and a part of it is extracted at a predetermined timing and outputs the trimmed image signal ST. The trimmed image is directly exposed to the unexposed film on the drum 2.

The exposure state of the scanning drum 2 to the unexposed film when the gate 23 is off may be arbitrarily determined depending on the trimming plate creation conditions.
For example, it may be left unexposed or fully exposed.

Therefore, according to the above embodiment, arbitrary trimming is possible in the color separation operation by the scanner, and only the trimmed portion can be exposed immediately, and the image signal reading operation by pre-trimming scanning has an extremely fast reading speed. Since this is performed by the image reading section 12, the time required for pre-scanning can be sufficiently shortened.

By the way, in this embodiment, the image signal obtained in the pre-trimming scan is reproduced on the monitor 21, and trimming is performed on the reproduced image surface, so if the pixel density of the reproduced image is low, the precision of trimming will also decrease. .

However, for example, if the image reading section 12 has 500 M and 500 N, and the image reading section 12 has a machining process of 10 cr IL.
In the case of scanning a ×8 CIIL original, the error in the trimming range allowed when the exposure magnification is 100% is ±0.1 (because the resolution pitch of the optical waveguide 12a is approximately 0.2). It is possible to maintain sufficient accuracy for practical use.

On the other hand, since a black and white monitor is sufficient for the monitor 21, the storage capacity required for the image memory 20 is smaller than that of the monitor 21.
When the total number of pixels of the image to be reproduced is set to 500 x 500, it is sufficient to use the 8th floor i11'#s bit for the picture and 1 bit for the trimming mark for each pixel, so the total size is 128 KB. This is sufficient, and there is no need to use one with too large a storage capacity.

In the above embodiment, the trimming is performed using a normal plate-making scanner equipped with scanning drums 1 and 2, and therefore the scanning drum 1 is set in the main body and the operations from pre-trimming scanning to main scanning are performed. Although the process can proceed as is, and an exposed film of a trimmed separation plate is obtained, in the present invention, only this pre-trimming scanning mechanism may be constructed as a dedicated device.

Therefore, in the embodiment in which a dedicated device is used in this way, 1. Pre-trimming scanning and main scanning are performed by separate devices, so a rotary encoder for detecting an arbitrary point on the scanning drum is used. A spear/meow enhancer is also required for each device, and additional data regarding the correspondence of scanning positions between both devices must be stored in the control device of the device that performs main scanning. Although necessary, since the pre-trimming scan and the main scan can be performed independently, flexibility can be given to the plate-making work.

Next, the effects of the present invention are listed as follows.■ According to the present invention, there is no need to create a mask plate when trimming a separated plate of a color original as in the conventional process, so plate making is possible. This reduces the amount of mask film used during work, and also helps speed up work.

■ If the trimming scanner according to the present invention is used for input in a computer layout sketch input system equipped with a large magnetic disk drive, it is often possible to retain only the data of the cropped image as a manual image, and the amount of retained data can be reduced. Since the amount of data is reduced, the magnetic disk back can be used effectively.

■ Compared to the case of performing trimming processing using a layout scanner system, the present invention allows trimming to be performed more easily and conveniently, and the system configuration is inexpensive as it does not require a large-scale one-table system. It has the advantage of being done.

As explained above, according to the present invention, it is possible to immediately obtain a cropped disassembled plate using a scanner, and the necessary pre-trimming scan can be performed in a short time. It is possible to provide a trimming scanner that can sufficiently reduce the time and cost required for.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the trimming scanner according to the present invention, FIGS. 2(a) and 2(b) are explanatory diagrams showing details of the image reading section, and FIGS. 6 and 4 show its operation. The explanatory diagram shown in FIG. 5 is the same (timing chart). 1... Reading scanning drum, 2... Exposure scanning drum, 3... Reading head, 4...・・・・・・
Exposure head, 5...ffj control device, 6...
...Drum drive section, 7... Image signal processing section,
8...Film light guiding section, 9...Rotary encoder, 10...Linear encoder, 11...Light source lamp, 12... Image reading section, 13... Light guiding section, 14... Photoelectric converter, 15... Data selector, 16...
...Analog Digital Transformer, 17...
Bus driver, 18... Buffer memory, 19
...Input/output controller S20...Image memory, 21...Monitor, 22...Coordinate designator, 23...Gate to! ! d Figure 3 Figure 4 269- False O Trout

Claims (2)

[Claims] (1) Comprising a reading scanning drum and a recording scanning drum,
In a rotating drum scanner that simultaneously reads image data from a document and emits the image data onto an unexposed film, images of a portion of the surface of the scanning drum that covers a PJf range are simultaneously read. a cylindrical image reading means capable of photographing fw iiJ; a memory for storing image data continued from a document by the cylindrical image reading means; a monitor for reproducing an image based on the image data read from the memory; A scanning range specifying means for specifying the reading scanning range of the image data is set, and the image data of the trimmed I A trimming scanner characterized by being configured such that exposure is controlled. (2) In the first term of the range of the special i'r'it+'7 search,
The cylindrical image reading means includes a plurality of optical waveguides each having a light incident end arranged in accordance with the surface shape of the reading scanning drum, and a plurality of photoelectric transducers attached to the light exiting end of the leading waveguide. A trimming scanner characterized by being configured with an element.