JP3760819B2 - Image processing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copier, a facsimile machine, and a multifunction machine image processing apparatus having multiple functions such as a copying function and a facsimile function.
[0002]
[Prior art]
In general, some image processing apparatuses have a function of recording an original image in a reduced size. Conventionally, reduction of the image processing apparatus of this type, as shown in FIG. 1, a method of recording by thinning out the main scan lines. In this case, as a premise, when the resolution of the recording unit (printer) is high and the resolution of the image to be recorded is low, the scanning lines of the recorded image are transferred to the printer a plurality of times and recorded as shown in FIG.
[0003]
[Problems to be solved by the invention]
Since the above-described conventional reduction method thins out the main scanning lines, there is a problem that some main scanning lines of the original image are lost and the image quality is deteriorated due to the reduction.
[0004]
The present invention has been made paying attention to the above problems, and an object thereof is to provide an image processing apparatus capable of reducing an image without causing deterioration of image quality.
[0005]
[Means for Solving the Problems]
The image processing apparatus according to claim 1 of the invention, conveying the recording sheet at a constant speed, an image processing apparatus for recording by the line head, a first processing means for reducing by thinning image, image to the line head And a second processing means for reducing the recording rate by narrowing the interval between the scanning lines, and the first processing means based on the resolution of the image to be recorded. Any one of the second processing means is selected and recorded in a reduced size.
[0006]
According to this image processing apparatus, either the first processing means or the second processing means is selected based on the resolution of the image to be recorded and reduced and recorded, and the second processing means is selected. In this case, the image quality does not deteriorate due to the reduction.
[0007]
In this image processing apparatus, it is preferable that the transfer clock to the line head is constant with respect to the change in the reduction ratio and is not changed.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to embodiments. FIG. 3 is a block diagram showing the configuration of a facsimile apparatus in which the present invention is implemented. This facsimile apparatus has an image reduction function, and includes a CPU (control unit) 1, NCU 2, MODEM 3, ROM 4, SRAM 5, image memory (DRAM) 6, control unit 7, CODEC (Coder and Decoder). 8, a CCD scanner 9, an image processing unit 10, an SRAM 11, a gate array 12, a high-speed SRAM 13, an LED head 14, a gate array 15, a motor driver 16, and a system bus 17.
[0009]
CPU1 controls each part which comprises this apparatus. The NCU 2 controls the connection with the telephone line network (PSTN) 18 and has a function for detecting transmission and reception of dial signals corresponding to the telephone number (including FAX number) of the other party. MODEM3 is an ITU (International Telecommunication Union) -T recommendation T.264. 30 based on the facsimile transmission control procedure according to 17, V. 27ter, V.I. The transmission data is modulated and the received data is demodulated in accordance with 29. Alternatively, in addition to these, V.P. 34, modulation of transmission data and demodulation of reception data are performed.
[0010]
The ROM 4 stores a program for controlling this device. The SRAM 5 temporarily stores data and the like. The image memory 6 temporarily stores received image data received via the NCU 2 and MODEM 3 and image data read by the CCD scanner 9. The operation unit 7 is used by the user to give instructions such as FAX transmission / reception and printing. The CODEC 8 encodes (encodes) the read image data by the MH, MR, MMR method, etc., and decodes (decodes) the received image data. The CCD scanner 9 reads the image data of the original when performing FAX transmission. The image processing unit 10 performs image processing on the document read by the CCD scanner 9 and stores it in the image memory 6. The SRAM 11 stores data to be encoded or decoded by the CODEC 8. The gate array 12 performs image processing on the image data to be printed and supplies a drive signal corresponding to the image data to be printed to the LED head 14. The LED head 14 exposes and prints a rotating photosensitive drum (not shown) according to the image data. A time, a leading edge margin, a trailing edge margin, a reduction ratio, and the like of a horizontal synchronization signal HSYNC described later are set in the gate array 12 in advance. The reduction process is performed during the printing process according to these settings.
[0011]
Next, printer reduction setting processing in the above embodiment will be described with reference to the flowchart shown in FIG. When the printer reduction setting process routine is entered, first, in step ST1, a data processing allowance time is calculated from the reduction magnification. Then, the process proceeds to step ST2.
[0012]
In step ST2, it is determined whether or not the processing for each line is in time even if the transfer cycle of each line of the line head is accelerated according to the reduction ratio from the calculated processing allowance time. If the process is in time, the process proceeds to step ST3. On the other hand, if the process is not in time, the process proceeds to step ST6.
[0013]
In step ST3, the time of the horizontal synchronization signal HSYNC is calculated from the magnification. For example, when the magnification is reduced from 100% to 90%, the period of the horizontal synchronization signal HSYNC is set to 90/100 of the period when the ratio is 100%. Next, the process proceeds to step ST4. In step ST4, set values such as the leading edge margin and the trailing edge margin are calculated based on the time of the horizontal synchronization signal HSYNC calculated in advance. Then, the process proceeds to step ST5. In step ST5, each set value is set in the gate array 12.
[0014]
When printing is performed with a printer having such a reduction setting, after opening the set leading margin, transfer is performed with a horizontal synchronization signal HSYNC with a fast cycle set according to the reduction ratio, and printing is performed. In a manner as shown in FIG. 5, a print having a narrower scanning line interval than that at the same magnification is made and reduced. In this case, since the scanning lines are not thinned out, the image quality does not deteriorate due to the reduction.
[0015]
In step ST6, a horizontal synchronization signal HSYNC with a magnification of 100% is set in the gate array 12. The period of the horizontal synchronization signal is not changed according to the reduction ratio. Next, the process proceeds to step ST7. In step ST7, set values such as a leading edge margin and a trailing edge margin at a magnification of 100% are set in the gate array 12. In this case, reduced printing is performed, but the magnification, leading edge margin, and trailing edge margin are set unchanged from 100%. Next, the process proceeds to step ST8. In step ST8, a reduction ratio is set for the gate array 12. Then, the printer reduction setting process ends.
[0016]
When the printer is set in the printer reduction setting process executed in steps ST6 to ST8, as shown in FIG. 1, the reduction printer prints out the scanning lines according to the reduction ratio.
[0017]
When reducing the image data stored in the image memory 6, the image data is transferred to the gate array 12 via the CODEC 8 and the SRAM 11. In the gate array 12, when the fast horizontal synchronization signal HSYNC is set according to the above setting, the scanning lines are pinned at that cycle, and the image data is supplied to the LED head 14 and printed as shown in FIG. . On the contrary, when the horizontal synchronization signal HSYNC is set to a period at the same magnification, thinning printing shown in FIG. 1 is performed.
[0018]
In this embodiment, the transfer clock is constant, and the main scanning direction is also reduced by dot thinning according to the reduction rate.
[0019]
【The invention's effect】
According to the first aspect of the present invention, the first processing means for thinning and reducing the image, and the transfer period of the image to the line head are made faster based on the reduction ratio than at the same magnification recording, thereby narrowing the space between the scanning lines. Second processing means for reducing and recording, and selecting either the first processing means or the second processing means based on the resolution of the image to be recorded for reduction recording. When the resolution data is reduced and printed, the second processing means is selected and the transfer cycle is shortened to reduce the print without degrading the image quality. When the high resolution data is reduced, If the processing cannot be performed in time due to the reduction ratio, the first processing means reduces the thinning, and a reduced image with the highest image quality can be obtained according to the performance of the apparatus.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining reduction by scanning line thinning.
FIG. 2 is a diagram for explaining smoothing by repeating the same scanning line.
FIG. 3 is a block diagram showing a configuration of a facsimile apparatus according to an embodiment of the present invention.
FIG. 4 is a flowchart illustrating printer reduction setting processing of the facsimile apparatus according to the embodiment.
FIG. 5 is a diagram for explaining reduction by increasing the transfer cycle in the facsimile apparatus according to the embodiment;
[Explanation of symbols]
1 CPU
2 NCU
3 MODEM
4 ROM
5 SRAM
6 Image memory 7 Operation unit 8 CODEC
9 CCD scanner 10 Image processor 11 SRAM
12 Gate array 13 High-speed SRAM
14 LED head 15 Gate array 16 Motor driver 17 System bus 18 Telephone line

Claims (1)

In an image processing apparatus that transports recording paper at a constant speed and records by a line head, a first processing means that thins out and reduces the image, and a transfer cycle of the image to the line head based on a reduction ratio from the same size recording. And a second processing means for reducing and recording the scanning line by narrowing it, and selecting either the first processing means or the second processing means based on the resolution of the image to be recorded An image processing apparatus which performs reduction recording.

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