JP2543305B2 - Recording control method in facsimile machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus having a high resolution ink jet recording section, and more particularly to a recording control method for recording image data having a resolution lower than the resolution of the recording section with high image quality.

[0002]

2. Description of the Related Art Recently, a so-called plain paper facsimile apparatus has become widespread in which a general cut sheet is used as a recording sheet without using a special sheet such as a thermal recording sheet. Most of the facsimile machines of this type have a recording section composed of a laser printer, but there is a facsimile machine which employs an ink jet printer as a recording section in order to realize a smaller size and lower cost plain paper facsimile machine.

In a plain paper facsimile apparatus equipped with an ink jet type recording unit, for example, a head for simultaneously recording 50 lines moves in the main scanning direction. The nozzles of the recording head are densely arranged, and some have a resolution of 300 DPI (dots per inch) in the sub-scanning direction, so that a sufficient resolution required for a facsimile device can be realized.

Even with a facsimile apparatus having a high-resolution ink jet recording unit of 300 DPI, the image data transmitted is not always 300 DPI, and depending on the communication partner, 200 DPI image data or 10 DPI image data may be transmitted.
Image data of 0DPI may be received. Therefore, when recording low-resolution image data, a process of enlarging and recording the image data according to the ratio with the resolution of the recording unit is required. However, the size of the image data subjected to the enlargement processing must fit within the size of the recording paper. Depending on the size of the received image data, simply enlarging the size of the image due to the relationship of resolution may exceed the paper size. Therefore, due to the relationship between the size of the received image data and the size of the recording paper, a reduction process is required in addition to the enlargement process.

For example, if the image data of 100 DPI is 300 D
When printing in the PI recording unit, if attention is paid only to the difference in resolution, the image data may be expanded to 300% and recorded. That is, each line of the image data is continuously recorded on the paper for three consecutive lines. However, if the image does not fit on the paper when enlarged in this way, the image data enlarged to 300% must be appropriately reduced. It is assumed that the appropriate enlargement ratio is 240% due to the relationship between the image data and the size of the paper. In this case, the image data enlarged to 300% is appropriately thinned out and reduced to 80% (300 × 0.8).
= 240).

Specifically, one line of data that is not the thinning target of the original image data is continuously recorded on the paper for three consecutive lines, and the data of the thinning target line is continuously recorded on the paper for two consecutive lines. This state is shown in FIG.
In this way, the number of times of overlapping recording is made different between the thinning target line and the other lines, and the low-resolution image data is printed by appropriately enlarging or reducing it in the high-resolution ink jet recording unit.

[0007]

In the case of an ink jet type recording section, since ink is ejected from a fine nozzle of a head which moves in the main scanning direction onto a sheet to perform recording, the recording line in the main scanning direction is an ink. Bleeding tends to make it thicker. In particular, when the same line data is overlapped and recorded on the paper for a plurality of lines as described above, there is a problem that the overlapping line becomes considerably thick and the density becomes too high, and the image quality is significantly deteriorated. In addition, as described above, when the number of times of overlapping recording differs depending on the line, the difference in the thickness of the line in the main scanning direction on the recorded image becomes noticeable, which also deteriorates the image quality.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to prevent deterioration of image quality as much as possible when recording low resolution image data by using a high resolution ink jet recording unit. It is an object of the present invention to provide a recording control method in a facsimile apparatus that is capable of performing the above.

[0009]

Therefore, in the present invention, the enlargement ratio is determined from the relationship between the resolution of the high resolution ink jet recording unit and the resolution of the low resolution received image data, and the size of the image data and the recording paper. The reduction ratio is determined from the relationship with the size of the image data, the thinning target line of the image data is determined according to the reduction ratio, and one line of data that is not the thinning target of the image data is continuously written on the paper for (m−n) lines. And duplicate recording (m and n are m> n
(Integer of ≧ 1), the n lines following the recording line are white lines, and one line of data, which is the thinning target of the image data, is continuously and repeatedly recorded on the sheet for (mn) lines, and The (n-1) line following the recording line was set as a white line.

[0010]

According to this recording control method, the data of the line which is not the thinning target is recorded on the paper at least once, and at least one white line is inserted immediately after the recording line. The data of the thinning target line is recorded on the paper the same number of times as the data of the non-thinning target line, but the number of white lines immediately after that is one less than the non-thinning target line (including zero).
Adjusting the number of white lines to be inserted serves as thinning for size adjustment.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a schematic construction of an embodiment of a facsimile apparatus to which the present invention is applied. In FIG. 1, C
PU1 is a microprocessor that controls the entire facsimile apparatus. User interface section 2
Includes an operation panel consisting of a display and a keyboard and its control unit. The document reading unit 3 includes an image scanner that reads an image of a transmission document. The code decoding unit 4 compresses and codes the image data from the document reading unit 3, and
The encoded image data stored in the memory 5 is decoded. Further, it is connected to the communication line via the network control unit 6 and the modem 7.

The ink jet type recording unit 8 is constructed so as to record 50 lines simultaneously by a head moving in the main scanning direction, and its resolution is 300 DPI. Head movement control of the recording unit 8, paper feed control,
The recording control unit 9 controls transfer of recording data. The recording control method of the present invention is embodied by the microprocessor of the recording control unit 9 as follows.

The process from the reception of image data to the recording is performed as follows. Image data received via the network control unit 6 and the modem 7 is temporarily stored in the memory 5. 1 in memory 5
The decoding process by the encoding / decoding unit 4 is started after the image data for the pages are prepared. The CPU 1 recognizes the resolution and the data size (the number of lines) of the image data stored in the memory 5, and notifies the recording control unit 9 of a parameter of a predetermined data format including both the resolution information and the size information. According to this parameter, the recording control unit 9 appropriately executes recording control of the image data decoded by the code decoding unit 4.

The code decoder 4 sequentially decodes the image data in the memory 5 and writes it in the line buffer A. The line buffer A has a capacity of at least 2 lines. The recording controller 9 sequentially transfers the line data in the line buffer A to the line buffer B as follows. Line buffer B
Has at least two sets of buffers each having a capacity of 50 lines, and when one set of buffers holds data for 50 lines,
The 50 lines of data are recorded on the paper at once by the recording head that moves in the main scanning direction as described above.
The paper is fed every time 50 lines are recorded.

Of course, the recording control unit 9 is provided with
The resolution information of 0 DPI is recognized, and the paper size information set in the recording unit 8 is also obtained from the recording unit 8. The resolution information and data size information of the image data to be recorded are stored in the CPU 1 in the form of the parameters.
Then, the recording mode of the image data is determined from the relationship between the resolution of the recording unit 8 and the paper size.

There are three types of resolution of received image data: 300 DPI, 200 DPI, and 100 DPI. Basically, recording of 300 DPI image data is performed in the 1 × mode, recording of 200 DPI image data is performed in the 1.5 × mode, and recording of 100 DPI image data is performed in the 3 × mode. The recording control method of the present invention relates to the 1.5 × mode and the 3 × mode, and the 1 × mode may be performed by the normal recording control.

3 when recording 100 DPI image data
The recording control in the double mode will be described in detail with reference to FIGS.

The recording control unit 9 recognizes that the resolution of the image data to be recorded is 100 DPI based on the parameter notified from the CPU 1, recognizes the data size, and simply triples the image data. When it is recorded, it is determined whether or not it exceeds the paper size, and if it exceeds the paper size, a reduction ratio (comprehensive enlargement ratio) for exactly matching the paper size is obtained. As a result, the overall enlargement ratio is determined to be, for example, 270% or 240% (this corresponds to reduction for 300% enlargement data). The thinning algorithm for this reduction is determined, and the thinning line selection method is determined. The above is the processing of step 201 in FIG.

In the next step 202, the data Di of one line aligned in the line buffer A is written twice in the line buffer B. That is, the same line data Di is redundantly transferred to two lines of the buffer B. Next step 203
At step 204, a thinning operation is performed according to the algorithm, and at step 204 it is determined whether or not the line data Di is a thinning target. If the line data Di is not the thinning target, the process proceeds to step 205 and the data D in the buffer B
The line next to the two lines in which i is written is set as a white line (all bits are set to "0"). When the line data Di is the thinning target line, step 205 is skipped and the white line is not inserted.

Then, the process proceeds from step 206 to 207, and the process target line is updated in synchronization with the progress of the decoding process by the code decoding unit 4 until the process of the image data of one page in the memory 5 is completed, and the process from step 202 to Repeat 205. In parallel with this data transfer process to the buffer B, the head of the ink jet recording unit 8 is activated and 50 lines of recording are performed every time 50 lines of data are prepared in the buffer B.

The state of data transfer from the line buffer A to the line buffer B and the insertion of the white line in the embodiment described in detail above is specifically shown in FIG. 3, and also in FIG. 4 (b).
The figure shows an example of recording when this recording control method is applied.
It is shown in comparison with the conventional example of (a). Here, when a white line is inserted, a white line runs in the main scanning direction, as shown in FIG.
It seems that the image quality of FIG.
Since it is ink jet recording, the ink bleeds on the paper, the lines before and after the white line are connected to each other, and the white line does not float.

As described above, since the white line is inserted and the number of times of overlapping recording of all lines is made equal, the adverse effect of the bleeding of a line having a large number of times of overlapping recording occurring when the number of times of overlapping recording is different is reduced, and The line width in the main scanning direction can be made constant.

Next, recording control in the 1.5 × mode when recording 200 DPI image data will be described with reference to FIGS. 5 and 6.

The basic control procedure is the same as in the triple mode described above, and the recording control unit 9 recognizes that the image data to be recorded has a resolution of 200 DPI and the data size by the notification from the CPU 1. The total enlargement ratio at the time of recording is obtained according to the information, and the thinning algorithm suitable for it is determined (step 501). Then, one line of data Di in the line buffer A is written once in the line buffer B, and when the data Di is not the thinning target, the line next to the transcribed line of the data Di in the buffer B is set as a white line. When the data Di is the thinning target, the white line is not inserted.

Another embodiment of the recording control in the triple mode when recording image data of 100 DPI will be described with reference to FIGS. 7 and 8.

In this embodiment, the data Di of the line buffer A is written once in the line buffer B, and when the data Di is not the thinning target, the two lines following the transcription line of the data Di in the buffer B are white lines. (Step 605). If the data Di is to be thinned out, only one line following the transfer line of the data Di in the buffer B is set as a white line (step 606).

In the above embodiment, the enlargement / reduction processing in the main scanning direction is not mentioned, but the resolution adjustment and the size adjustment in the main scanning direction are performed as necessary.

[0028]

As described in detail above, according to the recording control method of the present invention, when the low resolution received image data is recorded by the high resolution ink jet recording section, the enlargement ratio and the data size due to the difference in resolution are set. And the reduction ratio depending on the paper size, the overall enlargement ratio is determined, the thinning algorithm is determined accordingly, and the same number of duplicate recordings of the received image data on the paper of one line is performed regardless of whether the thinning target is used or not. The size is adjusted by adjusting the number of white lines to be inserted depending on whether or not thinning is to be performed. Therefore, the number of times of duplicate recording of the same line data is reduced as compared with the conventional method, and white lines are randomly inserted by that amount, and the adverse effect of ink bleeding in inkjet recording is reduced, and the recording image quality is improved. . Further, since the number of times of duplicate recording of each line data is constant, the line thickness in the main scanning direction does not vary depending on whether or not the line is a thinning target line, which also contributes to image quality improvement.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of a facsimile apparatus to which the present invention is applied.

FIG. 2 is a flowchart showing a procedure of a recording control method in a triple mode according to an embodiment of the present invention.

FIG. 3 is a conceptual diagram showing how data is transferred by a recording control method in a triple mode.

FIG. 4 is a diagram showing an example of recording by a recording control method in a triple mode, in comparison with a conventional example.

FIG. 5 is a flowchart showing the procedure of a recording control method in the 1.5 × mode according to an embodiment of the present invention.

FIG. 6 is a conceptual diagram showing how data is transferred by the recording control method in the 1.5 × mode.

FIG. 7 is a flowchart showing a procedure of a recording control method in a triple mode according to another embodiment of the present invention.

FIG. 8 is a conceptual diagram showing a state of data transfer in another embodiment of the triple mode.

[Explanation of symbols]

 4 Code Decoding Unit 5 Image Data Memory 8 Inkjet Recording Unit 9 Recording Control Unit

Claims (1)

(57) [Claims] 1. When recording low-resolution received image data on a sheet in a facsimile apparatus having a high-resolution ink jet recording unit, the enlargement ratio is determined from the relationship between the resolution of the recording unit and the resolution of the image data. At the same time, a reduction ratio is determined from the relationship between the size of the image data and the size of the recording paper, the thinning target line of the image data is determined according to the reduction ratio, and one line of data that is not the thinning target of the image data is Overlap recording is continuously performed for (mn) lines on the paper (m and n are integers of m> n ≧ 1), and n lines following the recording line are white lines, which are the thinning targets of the image data. One line of data is continuously and redundantly recorded on the sheet for (mn) lines, and the (n-1) line following the recording line is made a white line. And a recording control method in a facsimile apparatus.