JPH05268477A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent the generation of a tilted stepwise rugged line when a ruled line is not accurately coincident in the main scanning direction and the subscanning direction due to a tilt original. CONSTITUTION:Picture data of an original picture to be read are stored in a RAM 2, and a control section 1 detects a straight line included in an original. When the gradient of the straight line is within a preset prescribed range, a black picture element in the vicinity of the straight line is revised into a white picture element to cancel the straight line. Furthermore, after a picture element passing through e.g. a midpoint of the straight line in the main scanning direction or the subscanning direction is changed into a black picture element, corrected picture data are sent to a line 5 via a MODEM 7 and an NCU 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus accompanied with image data processing, such as a facsimile apparatus for transmitting and receiving image data obtained by reading an original image.

[0002]

2. Description of the Related Art In a facsimile machine, etc.,
While moving the document in the sub-scanning direction, the document image is read for each main scanning line by a line image sensor or the like. The image data obtained by this reading is transmitted via, for example, a public line, and the facsimile machine on the receiving side prints by a thermal head or the like based on the transmitted image data.

[0003]

However, in a high-ranking conventional facsimile apparatus or the like, when a document image includes ruled lines in the main scanning direction and the sub-scanning direction, it is caused by the inclination of the document during reading. If the ruled lines and the like do not match the main scanning direction and the sub-scanning direction, then on the printed image,
There is a problem in that the line becomes an unsightly line in the shape of an inclined staircase instead of a smooth horizontal or vertical line.

In view of the above points, the present invention forms an inclined stepped jagged line even when the ruled line or the like does not exactly match the main scanning direction or the sub scanning direction due to the inclination of the document. It is an object of the present invention to provide an image forming apparatus capable of preventing the above.

[0005]

In order to achieve the above object, the present invention provides a detecting means for detecting the inclination of a straight line included in an original image based on image data of the read original image, and a detecting means for detecting the inclination of the straight line. It is characterized in that when it is substantially parallel to the main scanning direction or the sub-scanning direction, it is provided with a correcting means for correcting the image data so as to change the straight line to the straight line in the main scanning direction or the sub-scanning direction.

[0006]

With the above arrangement, the detecting means detects the inclination of the straight line included in the original image based on the read image data of the original image, and the correcting means detects the inclination of the straight line in the main scanning direction or the sub-scanning direction. If they are substantially parallel, the image data is corrected so that the straight line is changed to a straight line in the main scanning direction or the sub scanning direction.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a facsimile apparatus as an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram showing a schematic circuit configuration of a facsimile machine. The facsimile machine has one or more CPs.
Control unit 1 including U for controlling the entire facsimile apparatus
RAM 2 for holding transmission data, reception data, telephone number, etc., auto dialer 3 for dialing, NCU 4 for controlling the line, and contents of the document set on the document table (not shown). A reading unit 6 that optically reads, a modem 7 that performs modulation / demodulation processing, a recording unit 8 that records on recording paper, a ROM 9 that stores a program necessary for the operation of the control unit 1, a ten-key pad, a one-touch key, etc. An operation panel 10 including a display unit 11 and a display unit 11 including an LCD are provided.

The basic transmission operation of the facsimile apparatus will be described with reference to the flowchart of FIG. In the following description, for simplification, an example is shown in which image data for one document is temporarily stored in the RAM 2 and then transmitted for each line. First, when the operator turns on a communication key or a one-touch dial key on the operation panel 10, the control unit 1 reads out the telephone number of the destination stored in the RAM 2, and the read telephone number is stored in the auto dialer 3 and The line 5 is dialed through the NCU 4 (S1).

After dialing, the reading unit 6 reads the original image, and the image data is stored in the RAM 2.
(S2). Specifically, as shown in FIG. 3, when a document 21 including ruled lines is read while being inclined in the main scanning direction and the sub scanning direction, the RAM 2 holds image data as schematically shown in FIG. 4, for example. To be done. Here, in general, ruled lines and the like often have a width extending over a plurality of lines or pixel digits, but for simplicity of description, a ruled line having a width of one line or one pixel digit will be described as an example. .

Next, a straight line included in the original image is detected based on the image data (S3). This straight line can be detected by, for example, Junichi Hasegawa et al., “Basic Techniques of Image Processing” (Technical Review Co.) p. This can be done by applying the processing as described in 83-85. Therefore, it is determined whether or not a straight line is detected (S4), and if not detected, the process proceeds to (S7) and the image data is transmitted as it is. It is determined whether it is within the range of the thresholds k1 and k2 that have been set or whether the reciprocal of the gradient m is within the range of the thresholds k3 and k4 (S5), and if it is within the range, the process proceeds to (S6). Correct the data.

That is, when the gradient m or its reciprocal is in a certain range, it is not a straight line which is intentionally inclined, and the straight line has a large degree of stepwise appearance, which is unsatisfactory in appearance and is therefore corrected. I do. Note that the determination in (S5) is not limited to the above, and for example, the upper limit (thresholds k2, k4)
Only the threshold value may be determined, or these threshold values may be arbitrarily changed.

To correct the image data in (S6), specifically, as shown in FIG. 5, black pixels in the vicinity of the detected straight line are changed to white pixels to erase the straight line, and at the same time, as shown in FIG. As shown in the figure, this is done by making the pixels in the main scanning direction or the sub scanning direction passing through the central portion of the straight line black pixels. The corrected image data is sent to the line 5 via the modem 7 and the NCU 4 after being subjected to predetermined data compression and the like (S7).

When the transmission of the image data for one original is completed, it is judged whether or not there is a next original (S8), and if there is, the same operation is repeated by returning to (S2). The connection is disconnected (S9), and the transmission operation ends.
The printing of an image based on the image data transmitted in this way is performed as follows by a facsimile apparatus having the same configuration. That is, when receiving the received information from the other party through the line 5, the NCU 4, and the modem 7,
Based on this incoming information, the control unit 1 drives the recording unit 8 to record the received information.

In the above pixel example, the width of the ruled line is 1
Although an example of a line or a one-pixel digit is shown, it is possible to reliably prevent the contour of the line from becoming stepwise even when the width is across a plurality of lines. Also, in the example above,
An example is shown in which the image data for one original is temporarily stored in the RAM 2 and then transmitted one line at a time. However, if the lines are read every several lines and are sequentially corrected and transmitted, The storage capacity of the RAM 2 can be kept small.

In the case of a facsimile machine, the inclination correction process may not be performed on the transmitting side as described above, but may be performed on the receiving side.

[0016]

As described above, according to the present invention,
Even if the document from which the image is read is tilted, the straight line that is included in the document image and is substantially parallel to the main scanning direction or the sub-scanning direction is changed to the straight line in the main scanning direction or the sub-scanning direction. The effect that it is possible to prevent the formation of ruled lines or the like on the inclined stepped jagged lines is obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic circuit configuration of a facsimile apparatus.

FIG. 2 is a flowchart showing a basic transmission operation.

FIG. 3 is an explanatory diagram showing a state in which a document including ruled lines is read while being inclined.

FIG. 4 is an explanatory diagram showing an example of image data stored in a RAM.

FIG. 5 is an explanatory diagram showing a state in which a straight line in image data is deleted.

FIG. 6 is an explanatory diagram showing a state in which a straight line in image data is corrected.

[Explanation of symbols]

 1 Controller 2 RAM 3 Auto Dialer 4 NCU 5 Line 6 Reader 7 Modem 8 Recording 9 ROM 10 Operation Panel 11 Display 21 Original

Claims (1)

[Claims] 1. A detection means for detecting the inclination of a straight line included in an original image based on the read image data of the original image; and the inclination of the straight line being substantially parallel to the main scanning direction or the sub-scanning direction, An image forming apparatus comprising: a correction unit that corrects image data so that the straight line is changed to a straight line in a main scanning direction or a sub scanning direction.