JPH03186058A - facsimile machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a facsimile machine having a function of transmitting and receiving images and having a function of recognizing an image sent from a transmitting side on a receiving side.

[Conventional technology]

Conventionally, for example, in the facsimile machine disclosed in Japanese Patent Application Laid-open No. 56-8958, when the receiving side recognizes the characters included in the transmitted image, in order to obtain a good recognition rate, the sending side Images were transmitted with high linear density.

Furthermore, in the facsimile device disclosed in Japanese Patent Application Laid-open No. 59-710066, if the receiving side cannot recognize the characters, the facsimile apparatus retransmits the text at a higher linear density.

[Problem to be solved by the invention]

However, there are some devices that can be recognized sufficiently on the receiving side even if the linear density is low, and in this case also,
Since the facsimile device disclosed in No. 8 transmits images at a high linear density, it has the disadvantage that it takes unnecessary transmission time. Also, JP-A-51-100
The facsimile device disclosed in JP-A-56-8958 usually transmits images at a low linear density, and in this respect, the transmission time can be shorter than that of the facsimile device disclosed in JP-A-56-8958. For example, if the font size of the transmitted image was small and the receiving side could not recognize the font, the image would need to be retransmitted at a high linear density, which would sacrifice transmission time. was there.

SUMMARY OF THE INVENTION An object of the present invention is to provide a facsimile device that is capable of transmitting an image at a linear density suitable for recognition to a receiving side in a short transmission time without sacrificing the transmission time. .

[Means to solve the problem]

In order to achieve the above object, the present invention provides a facsimile machine that sends and receives images, and in which the receiving side recognizes the image sent from the sending side. A detection means for detecting the size of the recognition target, a selection means for selecting the linear density of the image according to the detected size of the recognition target, and a transmission means for transmitting the image at the selected linear density to the receiving side. It is characterized by the presence of

[Operation] In a facsimile machine configured as described above, on the sending side, the size of the recognition target 1, for example, a character, is detected from the image, a line density corresponding to this size is selected, and the image is processed using this line density. Send to recipient.

When the character size is larger than a predetermined value, for example, the image is compressed and transmitted at a low linear density, and when the character size is smaller than the predetermined value, for example, the image is not compressed and is transmitted at a high linear density. In this way, an image is sent to the receiving side at a line density suitable for recognition, and the receiving side performs recognition processing based on this image.

[Example〕 Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a block diagram of an embodiment of a facsimile apparatus according to the present invention. In the apparatus of this embodiment, a transmitting apparatus 1 and a receiving apparatus 2 are connected via a communication line 10. As shown in FIG.

The transmitting device 1 includes an image reading unit 3 that reads an image at the highest possible line density, a character size detection unit 4 that extracts characters from the read image and detects the character size, and a character size detection unit 4 that extracts characters from the read image and detects the character size. A mode determining section 5 that calculates the density and outputs it as a linear density mode, an image processing section 6 that compresses the image from the image reading section 3 according to the linear density mode from the mode determining section 5, and an image processing section. and an image transmitting section 7 that transmits images from 6.

The receiving device 2 also includes an image receiving section 8 that receives and restores the image transmitted from the image transmitting section 7 of the transmitting device 1, and a recognition unit that performs recognition processing such as character recognition on the received and restored image. 9.

Currently, as a numerical facsimile device, the line density in the main scanning direction and the line density in the sub-scanning direction are each 8 lines/llm1.
, 7.7 lines/- high linear density and 8 lines/-
The document 20 shown in FIG. 2(a) is read and transmitted to the receiving section W, 2 using an apparatus having two linear density modes, one with a low linear density of 3.85 lines/-, and the other with a low linear density of 3.85 lines/-. The case where each character above is recognized will be explained.

First, the original 20 is sent to the image reading section 3 of the transmitting device l.
The maximum line density of the facsimile machine, that is, the line density in the main scanning direction and the line density in the sub-scanning direction, is 8 lines/am each.
7. The character size detection unit 4 cuts out each character "3" to "8" to be recognized from the read image in a mode of 7.7 lines/1m. As shown in Figure 2 (b), a rectangle extraction method using continuous components is used, and the minimum value of the sum of the height and width of each extracted rectangle is detected as the character size. . In the example in Figure 2 [b], the sum of the height r14 of the rectangle for the character "2" and the width "8" is "22", which is smaller than the sum of the heights of the rectangles for other characters and @. Since it is the minimum value, “22” is detected as the character size of the document 20.

In the mode determination unit 5, when the character size of the document 20 detected by the character size detection unit 4 is smaller than, for example, “20”, the line density in the main scanning direction and the line density in the sub-scanning direction are set to 8 lines/m and 7.7 lines. A mode with a high line density of /m is selected, and a mode with a low line density of 8 lines/w or 3°85 lines/m is selected when the character size is, for example, "20" or more.

By the way, in the case of the original 20 shown in FIG. 2(a), the document 20 shown in FIG.
As shown in b), the font size of original 1420 is F22.
”, which is larger than “20”, so the mode determining unit 5
selects a mode with a low linear density of 8 lines/m and 3.85 lines/lWI. When the mode determination unit 5 outputs a mode with a low line density, the image processing unit 6 sets the line density in the main scanning direction and the line density in the sub-scanning direction to 8 lines/l1, respectively.
ll, 7, 7 lines/related image reading unit 3
Compress high line density images from . Figure 3(a),
(b) is a diagram showing an example of this compression process, and the third
The character “2” with high line density shown in figure (a) is in the sub-scanning direction Y.
In even row L2. L4. "..." 10 pixels are thinned out, and as shown in FIG. 3(b), the line density in the main scanning direction and the line density in the sub-scanning direction are 8 lines each, /+ms+
, 3, compressed to a low linear density of 85 lines/Im. Next, the image transmitter 7 transmits the compressed image to the receiver 2 via the communication line 10. Receiving device 2
Then, the image receiving section 8 receives the transmitted image, restores it, and sends it to the recognition section 9, and the recognition section 9 receives the restored image,
In other words, in the process of recognizing 0 or more characters, the image transmitting unit 7 of the transmitting device 1 transmits the compressed image at a low linear density, so compared to the case where the image is transmitted as it is at a high linear density. , the transmission time can be reduced by about 1/2. Furthermore, even if the image is compressed and transmitted at a low linear density, the character size of the document 20 is larger than the predetermined value, so compression reduces the amount of information in the character, i.e., as shown in FIG. 3(b). The feature amount is less likely to be impaired, and as a result, the recognition unit 9 can obtain a predetermined recognition rate.

On the other hand, the font size of document 20 is set to the predetermined value "20J".
When the mode determining unit 5 selects a mode with a high linear density, the image processing unit 6 transmits the image (i) to the image transmitting unit 7 without compressing the high linear density image from the reading unit 3. The image transmitter 7 sends an image with a high linear density to the receiving device 2 via the communication line 1o.In this way, when the character size is smaller than a predetermined value, a high-density image that does not impair the characteristic amount of the character is sent. Since the information is sent to the recognition unit 9, the recognition unit 9 can obtain a predetermined recognition rate.

As described above, in this embodiment, the transmitting section automatically selects the linear density suitable for recognition processing according to the character size of the document, and transmits the image to the receiving side at the selected linear density. Therefore, the transmission time can be shortened as much as possible without sacrificing the recognition rate.

In the above embodiment, only two modes were explained, but more different modes may be provided, and the recognition target may be a symbol, a figure, etc. in addition to characters. .

Furthermore, the method of detecting the character size and the method of determining the mode are not limited to the above-mentioned example, and various modifications are possible.

〔Effect of the invention〕

As described above, according to the present invention, the transmitting unit detects the size of the recognition target from the image and transmits the image to the receiving side at a linear density selected according to the detected size of the recognition target. Therefore, an image with a line density suitable for recognition can be transmitted to the receiving side in an appropriate transmission time without sacrificing the transmission time.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of a facsimile apparatus according to the present invention, FIG. 2(a) is a diagram showing an example of a document, and FIG. A diagram for explaining how to cut out characters from the image, Figure 3 (a),
(b) is a diagram for explaining an example of image compression processing. DESCRIPTION OF SYMBOLS 1... Transmitting device, 2... Receiving device, 3... Image reading section, 4... Character size detection section, 5... Mode determining section, 6... Image processing section, 7...・Image transmission section, 8...
・Image receiving section, 9...Recognition section 2nd country figure

Claims (1)

[Claims] In a facsimile machine that sends and receives images, and the receiving side recognizes the image sent from the sending side, the sending side includes a detection means for detecting the size of the recognition target from the image, and a detection means for detecting the size of the recognition target from the image. 1. A facsimile apparatus comprising: a selection means for selecting a linear density of an image according to the size of a recognition target; and a transmission means for transmitting the image at the selected linear density to a receiving side.