JPH0620240B2 - Image signal generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention aims to enhance the outline of an image by C
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for generating an image signal using a storage type linear light receiving element such as a CD line sensor, and more particularly to an apparatus for generating an image signal weighted and added in a sub-scanning direction while vibrating the storage type linear light receiving element. .

(Prior Art and Its Problems) Conventionally, in a plate-making scanner or the like, when edge enhancement of an image signal having gradation is performed, a signal (S) of a sampling pixel and a larger sampling size centering on the sampling pixel are provided. From the so-called blur signal (U),
An operation of S + k (SU) (k is a constant) is performed. As a method for generating the blur signal U, various methods using an optical method and a digital circuit have been proposed. For example, Japanese Patent Application Laid-Open No. 59-141871 of the same applicant as the present application discloses in FIG. A blur signal generating method using a digital circuit as shown is disclosed. This blur signal generation method is simply performed by sequentially writing image signals to the image line memory 1 for a plurality of lines in the scanning order, and using the sub-scanning direction weighting device 2, the adder 3, and the divider 4 in the sub-scanning direction. After performing a weighted addition averaging with a predetermined weight to generate a blurred signal in the sub-scanning direction, the shift register 5 is used as a parallel signal, and the main scanning weighter 6 and the adder are added. 7 and the divider 8 are used to generate the blur signal U by performing weighted addition averaging in the main scanning direction. This method has an advantage that the mask size and the weighting of the weighted addition of the blurred image can be arbitrarily selected, but on the other hand, the large-capacity image memory 1
Have the problem of having to prepare. For example, assuming that the pixel detection width is 1500 lines / inch, the original image size is 12 inch width, and the mask size for generating the blur signal U is 30 lines, the required memory capacity is 1 pixel 1
This is 540 Kbytes. Therefore, in order to simplify the device, it is desired to reduce the memory capacity.

(Object of the Invention) Therefore, an object of the present invention is to solve the above-mentioned problems of the conventional technique and only to use an image memory having an extremely small capacity, and without losing the advantages of the conventional method in the sub-scanning direction. It is an object of the present invention to provide an image signal generation device capable of generating a blurred image signal by weighted addition.

(Means for Achieving the Object) In order to achieve the above object, in the image signal generating device according to the present invention, the storage-type linear light-receiving element is vibrated with a predetermined amplitude in the sub-scanning direction relative to the original image. By providing a vibrating means and intermittently activating the vibrating means in association with the movement of the storage-type linear light-receiving element in the sub-scanning direction,
The vibration mode and the non-vibration mode are alternately realized, and the image signal which is blurred by being weighted and added in the sub-scanning direction in the vibration mode is taken out, and the image signal which is not blurred in the non-vibration mode is taken out. A means for performing weighted addition and averaging in the main scanning direction is provided for the blurred image signal extracted in step (4) so that an image signal without blur and a blurred image signal which is independently weighted and added in the main and sub-scanning directions are obtained at the same time. I have to.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of an image signal generating apparatus according to the present invention. CCD line sensor 11
As shown in FIG. 2, the pixel array direction (longitudinal direction) is arranged on the image plane of the original image 13 as the main scanning direction according to the preset image formation magnification of the optical system 12. This CC
In response to the vibration signal from the vibration generator 14, the D line sensor 11 is configured to make a single reciprocating vibration in the sub-scanning direction on the image plane of the original image 13, as shown by the arrow in FIG. Has been done. The configuration for vibration is described, for example, in the Television Society Journal Vol. 37, No. 10 (1983), p. 826 ~
The bimoful piezoelectric device mechanism supported at both ends described in the article entitled "Swing CCD Image Sensor" published in 832 may be used.

The amplitude of the vibration is set in advance by changing the voltage waveform of the vibration signal from the vibration generator 14 to a width of three lines above and below, for example, as shown in FIG. The vibration cycle is set to be the same as the required charge storage time of the CCD line sensor 11, for example. In FIG. 3, the CCD line sensor 11 is at the sub-scanning position of the l-th line, and the movement to the next sub-scanning position (1 + 1-th line) is performed by moving the original image 13 in the y direction. The vibration of the CCD line sensor 11 and the movement in the sub-scanning direction are due to the relative movement with respect to the original image 13, and are not necessarily limited to the above-mentioned modes.

FIG. 4 is an explanatory diagram showing an example of the displacement amount (sub-scanning position) of the CCD line sensor 11 with respect to the time change t of image input. Period of vibration mode and stationary mode (T ₁ , T
₂ , T ₃ ...) Is set equal to the charge accumulation time, and in the odd-numbered cycles T ₁ , T ₃ , T _5, ..., The CCD line sensor 11 is in a vibrating state, and the even-numbered cycle T ₂ , At T ₄ , T ₆ ... The CCD line sensor 11 moves from one sub-scanning position to the next sub-scanning position through the vibration state and the stationary state. At this time, the original image 13 moves by one line in the y direction in FIG. The sensor 11 responds to the vibration signal from the vibration generator 14 to make a single reciprocating vibration in the sub-scanning direction.
Therefore, for example, in the third period T ₃ , when the CCD line sensor 11 that started to vibrate from the sub-scanning position between the 1st line and the 1 + 1th line ends a single reciprocating vibration and returns to the original position, the CCD Line sensor 11 is l +
I'm at the first line.

Returning to FIG. 1, the CCD line sensor 11 is driven by the drive signal from the CCD driver circuit 15 for each period T ₁ , T _2, ... In FIG. 4 to accumulate and read charges. At this time, the periods T ₂ , T ₄ , T _{6 in the} stationary state
In the period of ..., Lines l, l + 1, l +, respectively
A normal image signal for one scanning line (sharp signal) having no blur corresponding to No. 2 is obtained, while it is shown in FIG. 5 in the period of the vibration state periods T ₁ , T ₃ , T ₅ ... Thus, the weighted addition is performed for each line in the sub-scanning direction, and an image signal (blurring signal) that is blurred in the sub-scanning direction is obtained for one scanning line. The weighting function for this weighted addition is
It is possible to arbitrarily change the voltage waveform of the vibration signal from the vibration generator 14 so as to appropriately correct the time change rate of the relative speed of the CCD line sensor 11 with respect to the sub-scanning direction.

FIG. 6 is a timing chart showing the operation of the apparatus of FIG. 1 accompanying the reading of the image signal from the CCD line sensor 11, and FIG. 6 (a) shows the amount of displacement of the CCD line sensor 11 in the sub-scanning direction. ing. In FIG. 1, a clock generation circuit 16 generates a basic clock for image processing and the accumulation start pulse shown in FIG. 6 (b). The vibration generator 14 synchronizes with C in synchronization with the odd-numbered accumulation start pulse.
A vibration signal is given to the CD line sensor 11. In response to this vibration signal, the CCD line sensor 11, as shown in FIG. 6A, has odd-numbered periods T ₁ , T ₃ , T ₃ .
₅ , a single reciprocating vibration is performed in the sub-scanning direction.

On the other hand, the accumulation start pulse of FIG. 6B is given to the CCD line sensor 11 via the CCD driver circuit 15, and in response to this, the CCD line sensor 11 accumulates the charge at the beginning of each cycle. To start. The CCD driver circuit 15 sends the accumulation start pulse to the CCD line sensor 1.
6 is applied, the charge read pulse shown in FIG. 6 (c) is created based on the basic clock from the clock generator 16 and is applied to the CCD line sensor 11. The CCD line sensor 11 synchronizes with this charge read pulse,
The charges of one line accumulated in the previous cycle are sequentially read out pixel by pixel.

The read image signal is converted into a digital signal in the A / D converter 17 and given to the selector 18.
FIG. 6 (d) shows a digital image signal output from the A / D converter 17, and S (l-
1), S (l), S (l + 1) are l-1, l,
It represents the sharp signal of the (l + 1) th line, and
U (l), U (l + 1) and U (l + 2) represent blur signals corresponding to the l, l + 1 and l + 2 lines, respectively.

The selector 18 includes the clock generator 16 and the selector 18 shown in FIG.
In response to the accumulation start pulse of, the S channel is selected in synchronization with the odd-numbered accumulation start pulse, and the U channel is selected in synchronization with the even-numbered accumulation start pulse (here, FIG. 6 (a)). Note that there is a schematic delay of 1 accumulation time between (d)). Therefore, odd-numbered period _{T 1, T 3, T 5} ... In sharp signal outputted from the A / D converter 17 S (l-1), S (l), S
(L + 1) ... Are guided to the delay circuit 19 and the blur signals U (l), U (l + 1), U output from the A / D converter 17 in the even-numbered periods T ₂ , T ₄ , T ₆ ... (L +
2) ... Is guided to the line memory 20.

The line memory 20 has a capacity capable of storing an image signal for one line in the main scanning direction, and the memory control circuit 21 controls writing / reading. Memory control circuit 21
Generates the write / read control signal / R and the address signal Addr of FIG. 6 (e) based on the basic clock and the accumulation start pulse from the clock generation circuit 16.
This is given to the line memory 20. The line memory 20 writes data in response to a "low" / R signal and reads the written data in response to a "high" / R signal.

FIG. 6 (f) shows the timing at which the contents stored in the line memory 20 are read out. For example, the blur signal U (for one line written in response to the / R signal of "low" in the T ₂ period. l) is “high” in the next T ₃ period
Is read in response to the / R signal.

Now, for convenience of explanation, attention is paid to the T ₃ period in FIG. At this time, the selector 18 selects the S channel in synchronization with the odd-numbered accumulation start pulse, and thus the sharp signal S (l) is output from the S output terminal of the selector 18. On the other hand, the blur signal U (l) is read from the line memory 20 in response to the "high" / R signal. The blur signal U (l) read from the line memory 20 is given to the main scanning direction weighted averager 22,
There, a weighted averaging in the main scanning direction is performed. This weighted averaging in the main scanning direction may be carried out by any known method, for example, Japanese Patent Laid-Open No. 59-14 mentioned above.
For example, the method disclosed in No. 1871 can be adopted.

The delay circuit 19 in the S channel is for correcting the delay of the image signal generated in the weighted average averaging unit 22 in the main scanning direction, and is substantially equivalent to the required calculation time in the weighted average averaging unit 22 in the main scanning direction. It has a delay clock number. The number of delay clocks changes depending on the addition mask width in the main scanning direction.

FIG. 6 (g) shows the sharpness signal applied to the S input of the sharpness calculation circuit 23 via the delay circuit 19, and FIG. 6 (h) shows the sharpness calculation circuit via the main scanning direction weighted averager 22. 23 shows a blur signal applied to the U input of 23. For example, in the above T ₃ period,
The U (l) signal read from the line memory 20 in response to the “high” / R signal is delayed by the time t due to the arithmetic processing of the weighted average averaging unit 22 in the main scanning direction, and the U (l) signal of the sharpness arithmetic circuit 23. The S (l) signal which is supplied to the U input and is output from the selector 18 to the S channel side in synchronization with the odd-numbered accumulation start pulse at this time passes through the delay circuit 19 and has the same time width t. And is given to the S input of the sharpness calculation circuit 23. In this way, the sharp signal S and the blur signal U input to the sharpness calculation circuit 23 are always CC
The signal is synchronized with each pixel number of the D line sensor 11.

The sharpness calculation circuit 23 applies S + k for each pixel to the input sharpness signal S and blur signal U.
The calculation of (S−U) is performed to form an image signal including image edge enhancement. A specific configuration for performing this calculation is shown in, for example, FIG. 10 described above. here,
k is a coefficient representing the degree of sharpness, and is an amount that changes according to sharpness.

(Effects of the Invention) As described above, according to the present invention, the vibrating unit vibrates the storage-type linear light-receiving element in the sub-scanning direction, so that the image signal is blurred by weighted addition in the sub-scanning direction. In addition, the means for performing the weighted addition averaging in the main scanning direction is applied to the blurred image signal extracted in the vibration mode, and the blur-free image signal and the blur added independently in the main and sub-scanning directions are provided. Since it is configured to obtain the image signals simultaneously, a memory for storing image data for a plurality of lines is not required, and an arithmetic circuit for weighted addition in the sub-scanning direction is not required, and the device The price can be reduced and the size can be reduced.

Further, the vibrating mode and the non-vibrating mode are alternately realized by intermittently activating the vibrating means in association with the movement of the storage-type linear light receiving element in the sub-scanning direction, and an image signal blurred in the vibrating mode is realized. Since the image signal without blur is taken out in the non-vibration mode, one storage-type linear light receiving element can be used for both the blurred image signal and the non-blurred image signal, which simplifies the configuration. Has the effect of becoming.

In addition, a blurred image signal and a non-blurred image signal can be obtained due to the vibration and non-vibration of the light receiving element itself, and different control is performed on the incident light to the light receiving element for the blurred image signal and the unblurred image signal. Since there is no need to provide a means for performing, there is an effect that the configuration becomes simple.

The weighting of the weighted addition in the sub-scanning direction can be easily changed by controlling the changing speed of the vibration, and the mask size in the sub-scanning direction can be easily changed by making the amplitude of the vibration variable. You can

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an image signal generating device according to the present invention, FIG. 2 is an explanatory diagram showing an image detecting optical system, and FIG. 3 is an explanatory diagram of an image detecting method in the present invention.
FIG. 4 is an explanatory diagram of the displacement amount of the CCD line sensor with respect to time change, FIG. 5 is a diagram schematically showing weighted addition in the sub-scanning direction, and FIG. 6 is a timing chart showing the operation of the apparatus of FIG. FIG. 7 is a block diagram showing a conventional contour line emphasis circuit. 11, 31 ... CCD line sensor 14 ... Vibration generator 15 ... CCD driver circuit 16 ... Clock generation circuit 17, 37 ... A / D converter 18 ... Selector 19 ... Delay circuit 20 ... Line memory 21 ... Memory control circuit 22 ... Main scanning direction weighted averaging device 23 ... Sharpness calculation circuit

Claims (4)

[Claims] 1. A pixel array direction of a storage type linear light receiving element is defined as a main scanning direction, and the storage type linear light receiving element is moved relative to an original image in a sub scanning direction perpendicular to the main scanning direction. In an apparatus for generating an image signal, a vibrating means for vibrating the storage-type linear light-receiving element with a predetermined amplitude in the sub-scanning direction relative to an original image is provided, and the vibrating means is provided for the storage-type linear light-receiving element. By intermittently activating in association with the movement in the scanning direction, the vibration mode and the non-vibration mode are realized alternately, and the blurred image signal weighted and added in the sub-scanning direction in the vibration mode is taken out,
A means for taking out a non-blurred image signal in the non-vibration mode and further performing a weighted averaging in the main scanning direction with respect to the blurring image signal taken out in the vibration mode is provided. An image signal generating device, wherein a blurred image signal which is independently weighted and added in a scanning direction is simultaneously obtained. 2. The image signal blurred in the sub-scanning direction in the vibration mode is a blur signal used for image contour enhancement, and the image signal without blur in the non-vibration mode is a sharp signal. The image signal generation device according to item 1. 3. The image signal generating apparatus according to claim 1, wherein the vibrating means includes means for changing the amplitude of vibration to a desired value. 4. The image signal generating device according to claim 1, wherein the vibrating means includes means for changing a displacement speed of vibration to a desired value.