JP3264017B2 - Image transmission apparatus and method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmission apparatus and method , and more particularly, to an image transmission apparatus and method capable of transmitting color images and monochrome images.

[0002]

2. Description of the Related Art A facsimile system for transmitting a black-and-white image via a communication line is well known, but a color facsimile apparatus capable of transmitting and receiving a color image via a communication line has also been proposed. In order to secure connectivity with a conventional facsimile apparatus for monochrome images, it is common to provide a G3 or G4 standard monochrome image transmission function. MR or MMR coding is adopted as a compression method for a monochrome image, and a JBIG method or a JPEG method is used as a compression method for a color image.

Whether color transmission or black-and-white transmission is performed depends on whether the original is color or black-and-white, the receiving capability of the destination, and the intention of the sender.

[0004] The receiving capability of a destination can be generally known in the course of negotiation of pre-processing for facsimile transmission. Alternatively, when the reception capability can be registered in the registration table of the telephone number of the communication partner, the registration table may be referred to.

[0005] Whether an original is color or black and white is specified by an operator on an operation panel. This operation also serves as input of the sender's intention.

In the prior art, image information read by an image scanner is temporarily color-coded regardless of whether it is a color image or a monochrome image, and is temporarily stored in a hard disk device. Then, in the case of color transmission, the compression information read from the hard disk device is transmitted, and in the case of black and white transmission, the color coded data is first decoded and black and white coded, and the black and white coded information is transmitted. .

[0007]

As described above, when the input of the sender's intention and the input of the distinction between the color original and the black-and-white original are combined, for example, a color original to be transmitted in color is mistaken for a black-and-white original, and the monochrome original is transmitted. Is selected, color transmission cannot be performed, and if a monochrome document is mistakenly recognized as a color document and color transmission is selected, an abnormally long time is required for transmission.

Further, in the conventional example, even if a document has a plurality of pages, if a part of the document has a color portion, the entire document must be transmitted in color, the amount of transmission data becomes enormous, and transmission takes a long time. There is a disadvantage that.

[0009] In the conventional example, a large amount of data is stored in the hard disk device even in the case of a black-and-white document because color coding is performed and the image data is temporarily stored in a hard disk device or the like irrespective of whether the document is a color document or a monochrome document. As a result, the amount of black-and-white documents that can be transmitted at one time is limited.

[0010] An object of the present invention is to provide an image transmitting apparatus and an image transmitting method which solve these disadvantages.

[0011]

An image transmitting apparatus according to the present invention is an image transmitting apparatus for transmitting an image to a partner machine,
Input means for inputting an image, and
Determining means for determining a color area of the image;
Performs black and white compression encoding on all areas of the image
Generate coded data and color data for the color area.
To generate color encoded data by performing compression encoding for
Processing means and the black and white encoded data generated by the processing means.
Storage means for storing data and color encoded data respectively
And a partner machine that only has the ability to receive black and white encoded data
Transmits the stored black-and-white coded data to
It has the ability to receive black and white encoded data and color encoded data.
The stored black-and-white coded data is
And transmission means for transmitting color encoded data.
It is characterized by the following .

Image transmission method according to the [0012] The present invention relates to an image the opponent
This is an image transmission method for transmitting images to
Force step and, based on the input image,
A determining step of determining a color area;
Black-and-white coded data by performing compression coding for black and white
And generates a color compression code for the color area.
Processing steps for performing colorization and generating color encoded data
And the black and white coded data generated by the processing steps.
Memory and color coded data, respectively.
And a partner who only has the ability to receive black and white encoded data
The stored black-and-white coded data is transmitted to the
And the ability to receive black and white coded data and color coded data
Is stored in the black-and-white code
Transmission step for transmitting encoded data and the color encoded data.
And a tip.

[0013]

[0014]

[0015]

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of the present invention.

In FIG. 1, reference numeral 10 denotes an MP for controlling the whole.
U and 12 are ROMs for storing a control program and constant data of the MPU 10, RAM for temporarily storing control variables and the like, 16 for an image memory for storing image data to be transmitted and received, and 18 for compressing image information to be transmitted and received, for example. Large auxiliary storage device (for example, hardware
Disk device).

Reference numeral 20 denotes a black-and-white compression / decompression circuit for compressing / decompressing a black-and-white image according to the MMR coding method.
This is a color compression / decompression circuit that compresses / decompresses data using the PEG encoding method. Reference numeral 24 denotes a color image for color transmission.
This is a binarizing circuit for converting a value. In the present embodiment, the monochrome transmission / decompression circuit 20 is also used for color transmission. That is, the color image to be transmitted is first binarized by the binarization circuit 24,
The output of the value conversion circuit 24 is compressed by the monochrome compression / decompression circuit 20.

Reference numeral 26 denotes a key input unit 26a and a display unit 26
b is an operation panel provided with b. 28 is the operation panel 2
6 is a panel control circuit for controlling the control panel 6.

Reference numeral 30 denotes an image reading device (a so-called image scanner), and 32 denotes an image output device (for example, a color scanner).
Printers and 34 are image input / output control circuits for controlling the image reading device 30 and the image output device 32. The image input / output control circuit 34 includes a color determination circuit 34a that determines whether or not the input image is a color image based on the image data from the image reading device 30.

A communication circuit 36 is connected to a communication line.
Is a communication control circuit for controlling communication via the communication circuits 36, 36. In this embodiment, two communication lines are available.

A DMA control circuit 40 for controlling a DMA (Direct Memory Access) transfer of image data;
42 is a system bus of the illustrated circuit. That is, MP
U10, ROM 12, RAM 14, image memory 16, auxiliary storage device 18, monochrome compression / expansion circuit 20, color compression / expansion circuit 22, binarization circuit 24, panel control circuit 2
8, image input / output control circuit 34, communication control circuit 38 and D
The MA control circuits 40 are interconnected via a system bus 42.

The operation of this embodiment will be described. FIG. 2 is a flowchart showing an operation of inputting an image by the image reading device 30, and FIG. 3 shows an example of each piece of page information input by an image.

The MPU 10 applies an image reading start command to the image input / output control circuit 34 via the system bus 42. At the same time, the MPU 10
An area for storing information of each page on which an image has been read is secured (S1). The image input / output control circuit 34 starts reading scanning of the image reading device 30 according to the command (S2). The image reading device 30 outputs color image data obtained by scanning a document to the image input / output control circuit 34 in the order of RGB points, for example.

The color determination circuit 34a of the image input / output control circuit 34 determines whether the image data from the image reading device 30 is color or monochrome on a pixel-by-pixel basis (S3). The color determination circuit 34a stores the number of color pixels and the total number of pixels for each page.

The image input / output control circuit 34 transfers the image data supplied from the image reading device 30 to the DMA control circuit 4.
0 through the system bus 42 under control of
DMA transfer to the decompression circuit 22 is performed. The color compression / expansion circuit 22 compresses this image data by the JPEG method (S
4) The compressed data is transferred to the auxiliary storage device 18 via the system bus 42 and stored (S5).

Until the processing of one page is completed (S
6), color discrimination (S3), color compression (S4), and accumulation in the auxiliary storage device 18 (S5) are repeated).

When the processing for one page is completed (S6),
The MPU 10 reads the color / monochrome determination threshold stored in the RAM 14. It is preferable that the color / monochrome determination threshold can be freely changed by the key input section 26a or by a special means. Then, the occupation ratio of the color pixels in one page is calculated from the number of color pixels held by the color determination circuit 34a and the total number of pixels, and is compared with a color / monochrome determination threshold value.
It is determined whether the document is a color document or a monochrome document (S7). As shown in FIG. 3, in addition to the discrimination result, information such as the encoding method, paper size, resolution, and encoded data amount is stored in the RAM 14 as page information (S8).

When all pages of the document to be transmitted are read by the image reading device 30, the document is transmitted to the communication partner. FIG. 4 shows a transmission flowchart of one page to be transmitted.

The MPU 10 reads out the page information of the page to be transmitted from the RAM 14 (S11), and if it is a color page (S12), the MPU 10
The encoded data stored in the communication circuit 36 is read out and transferred to the communication control circuit 38 via the system bus 42.
To the communication line (S16).

If the page to be transmitted is a monochrome page (S12), the MPU 10 reads out the color coded data stored in the auxiliary storage device 18 and
2 to the color compression / decompression circuit 22. The color compression / expansion circuit 22 expands the color encoded data (S13). The color image data restored by the color compression / expansion circuit 22 is applied to a binarization circuit 24, where it is binarized (S14). The output of the binarization circuit 24 is applied to the black and white compression / decompression circuit 20 and subjected to MMR encoding (S15). This encoded data is transmitted to the system bus 42
Is transferred to the Tsushin control circuit 38 via the communication circuit 36, and is output from the communication circuit 36 to the communication line (S16).

As described above, in this embodiment, the color
The page transmits the color-compressed encoded data in advance,
In the case of a black and white page, after color restoration, binarization and M
MR encoding and transmission.

In FIG. 4, the JPEG system is used for the color compression system for storing the color image information in the auxiliary storage device 18 and the image transmission compression system. However, the JBIG system and other color compression encoding systems are used. It goes without saying that you can do it. Further, the color compression method used when color image information is stored in the auxiliary storage device 18 and the compression method used during image transmission do not necessarily have to match. If they do not match, the same restoring and encoding processes as in S13, 14, and 15 for black and white pages are performed on color pages.

In FIG. 4, the color coding and the black and white coding are selected according to whether the original page is color or black and white. Needless to say, the capability of the receiving side may be added to this. , And transmits the encoded data in accordance with the encoding method according to the receiving capability of the communication partner.

The means for determining whether a page is a color page or a monochrome page is not limited to the above embodiment. If there is a color pixel of a predetermined level or more in a line unit or a dot unit, it may be determined that the color pixel is present, and that the other pixels are black and white.

According to the above embodiment, whether a document is color or black and white is automatically determined, so that an operation error such as color transmission of a black and white document can be completely prevented. Further, the operator does not need to manually set color transmission or black-and-white transmission for each page, so that operability is significantly improved.

Next, a description will be given of a second embodiment in which color coding and black-and-white coding are automatically selected according to whether a document is color or black and white. The hardware configuration is the same as FIG.
The control program for the MPU 10 is different.

FIG. 5 shows a flow chart for reading an original in the second embodiment. As in the case of FIG. 3, it is assumed that the first page is black and white, the second page is color, and the third page is black and white.

The MPU 10 applies a prescan command to the image input / output control circuit 34 via the system bus 42 (S21). The image input / output control circuit 34 causes the image reading device 30 to start high-speed scanning in response to the prescan command. The image reading device 30 outputs color image data obtained by scanning a document to the image input / output control circuit 34.

The color determination circuit 34a of the image input / output control circuit 34 determines whether the image data from the image reading device 30 is color or black and white in pixel units, and counts the total number of pixels per page and the number of color pixels. MPU10 is RAM1
The color / monochrome determination threshold value stored in the color determination circuit 34a is read out, and the occupation rate of the color pixels in one page is calculated from the number of color pixels and the total number of pixels held by the color determination circuit 34a.
It is determined whether the document is a color document or a monochrome document by comparing the threshold value with a monochrome determination threshold value (S22). It is preferable that the color / monochrome discrimination threshold stored in the RAM 14 can be changed by the key input unit 26a or by a special means.

When the discrimination result is black and white (S23), the MPU
10 sets the page information of the monochrome page in the RAM 14 (S24). As shown in FIG. 3, the page information includes color / black / white distinction, an encoding method, a paper size, a resolution, an encoded data amount, and the like. The MPU 10 applies a scan command to the image input / output control circuit 34, and the image input / output control circuit 34 starts reading scan of the image reading device 30 according to the scan command (S25).

The image data read by the image reading device 30 is converted into black and white data by the image input / output control circuit 34 (S26). This black and white data is transferred to the black and white compression / decompression circuit 20 under the control of the DMA control circuit 40.
It is MR-encoded (S27) and stored in the auxiliary storage device 18 (S28).

When the determination result is color (S23), RA
The page information of the color page is set in M14 (S29). The MPU 10 applies a scan command to the image input / output control circuit 34 and
Is the image reading device 3 according to the scan command.
A reading scan of 0 is started (S30). The image data read by the image reading device 30 is transferred to the color compression / decompression circuit 22 via the image input / output control circuit 34 and the system bus 42, and compressed by the JPEG method (S
31). The compressed data is stored in the auxiliary storage device 18 (S32).

In FIG. 5, JBIG is also used as a color compression method for storing color image information in the auxiliary storage device 18.
It goes without saying that a system and other color compression coding systems can be used. Further, the color compression method used when color image information is stored in the auxiliary storage device 18 and the compression method used during image transmission do not necessarily have to match.

Next, a description will be given of a third embodiment in which one page is divided into a color image and a black-and-white image, and color transmission and black-and-white transmission are performed respectively. The hardware configuration is the same as that of FIG. 1, and the control program for the MPU 10 is different.

FIG. 6 shows a flow chart for reading an original in the third embodiment. As shown in FIG. 7, the original has three color image portions, namely, color block # 1,
The color block # 1 has start points (20, 20) and end points (90, 7) with # 2 and # 3 as the base point (0, 0) and the lower right (180, 250) at the upper left of the document reading range.
0), the rectangular area specified by the color block # 2 at the start point (10, 80) and the end point (170, 150), and the color block # 3 at the start point (80, 16).
0) and an end point (160, 230). Other areas include monochrome images such as characters.

The MPU 10 applies a pre-scan command to the image input / output control circuit 34 via the system bus 42. At the same time, the MPU 10
An area for storing information of each page on which an image has been read is secured (S41). The image input / output control circuit 34 causes the image reading device 30 to start high-speed scanning in response to the prescan command. The image reading device 30 outputs color image data obtained by scanning a document to the image input / output control circuit 34.

The color determination circuit 34a of the image input / output control circuit 34 determines whether the image data from the image reading device 30 is color or black and white in pixel units. In this embodiment, the color discrimination circuit 34a outputs a flag signal indicating whether the image is color or black and white on a pixel-by-pixel basis to the MPU 10. MPU 10
The flag signal recognizes the area occupied by the color image in one page, that is, the coordinate position of the color block, and stores the coordinate signal of each color block as page information in the RAM 1.
4 (S42). The coordinates of the reading range of the document are also stored in the RAM 14 as black and white blocks.

In the document example shown in FIG. 7, as shown in FIG. 8, the coordinate data of three color blocks and one black and white block indicating the document reading range are stored in the RAM 14.

After this prescan, the MPU 10 applies a scan command to the image input / output control circuit 34 (S43). The image input / output control circuit 34 starts the reading scan of the image reading device 30 in response to the scan command. The read image data is stored in the image memory 1
6 (or RAM 14).

The MPU 10 refers to the page information stored in the RAM 14, transfers the image data in the color blocks # 1 to # 3 from the image memory 16 to the color compression / expansion circuit 22, and compresses the image data in the JPEG format. (S4
4). The color image data compressed for each color block is stored in the auxiliary storage device 18 (S45). FIG. 8 shows an example of the compressed data amount of each color block for reference.

After the color compression of all the color blocks of one page is completed, the MPU 10 transfers all the image data of one page from the image memory 16 to the binarization circuit 24, binarizes the image data, and then performs the monochrome compression. The data is transferred to the / decompression circuit 20 and subjected to MMR encoding (S46). This encoded data is stored in the auxiliary storage device 18 (S47).

The image reading process is performed on all pages of the original document to be transmitted. Thereby, the auxiliary storage device 18
Stores MMR encoded data of all pages of the original document to be transmitted and JPEG encoded data of the color area of each page.

For the color block portion, the MMR
Although encoded data and JPEG encoded data coexist,
Since the amount of MR encoded data is very small compared to the amount of JPEG encoded data, there is no burden.

When the receiver has only the capability of receiving MMR encoded data, the MPU 10 only needs to transmit the MMR encoded data stored in the auxiliary storage device 18.

When the receiver uses JPEG encoded data and MMR
If both of them have the capability of receiving encoded data, the MPU 1
0 transmits the MMR coded data stored in the auxiliary storage device 18 for each page of the document first, and then transmits the coordinate data of each color block and its JPEG coded data. On the receiver side, the previously received MMR
Decodes the encoded data, expands the black and white image data in the image memory, and overwrites the restored image of the JPEG encoded data to be subsequently received at a storage position in the image memory according to the coordinate data of each color block. I do. As a result, the image memory of the receiver stores image data in which the color portion of one page is expressed in color, and the other portions are expressed in black and white. This image data is read out and printed out by a color printer.

In FIG. 6, the color portion is automatically determined.
The operator may manually specify. For example, an image of the prescan result is displayed on a monitor or the like, and a color transmission portion is designated by coordinate designation means such as a pen.

In FIG. 6, JBIG is also used as a color compression method for storing color image information in the auxiliary storage device 18.
It goes without saying that a system and other color compression coding systems can be used. Further, the color compression method used when color image information is stored in the auxiliary storage device 18 and the compression method used during image transmission do not necessarily have to match.

In FIG. 6, the color portion and the other black and white portions are each compressed and temporarily stored in the auxiliary storage device 18. However, the color portion may be stored in the RGB format, and the black and white portion may be stored in the binary raw data format. Needless to say, the occupied storage amount of the auxiliary storage device 18 can be reduced.

[0061]

As can be easily understood from the above description, according to the present invention , regardless of the receiving capability of the partner device, the speed can be reduced.
At the same time, you can send the image,
Store color encoded data only in the color area
Occupy less storage space.
Wear.

[Brief description of the drawings]

FIG. 1 is a basic schematic block diagram of an embodiment of the present invention.

FIG. 2 is a flowchart for reading a document according to the first embodiment.

FIG. 3 is an example of page information according to the first embodiment.

FIG. 4 is a transmission flowchart of the first embodiment.

FIG. 5 is a flowchart for reading a document according to the second embodiment.

FIG. 6 is a flowchart for reading a document according to the third embodiment.

FIG. 7 is an example of a document for the third embodiment.

FIG. 8 shows page information for the document shown in FIG.

[Explanation of symbols]

10: MPU 12: ROM 14: RAM 16: Image memory 18: Auxiliary storage device 20: Black and white compression / expansion circuit 22: Color compression / expansion circuit 24: Binarization circuit 26: Operation panel 26a: Key input unit 26b: Display Part 28: Panel control circuit 30: Image reading device
32: Image output device 34: Image input / output control circuit 34
a: Color discrimination circuit 36: Communication circuit 38: Communication control circuit 40: DMA control circuit 42: System bus

Claims (2)

(57) [Claims] (1)An image transmission device that sends images to the other party
So, Input means for inputting an image, A color area of the image based on the input image;
Determining means for determining The entire area of the image is subjected to black-and-white compression
Generate black encoded data, and color the color area.
And perform color coding to generate color-coded data
Processing means; The black and white encoded data generated by the processing means and the color
Storage means for respectively storing encoded data; Compatible with other devices that only have the ability to receive black and white encoded data
Then, the stored black and white encoded data is transmitted,
Has the ability to receive encoded data and color encoded data
The stored black-and-white coded data and
Transmission means for transmitting color-coded data thing
An image transmission device characterized by the above-mentioned. (2)With an image transmission method that sends images to the other
So, An input step of inputting an image, The color area of the image is determined based on the input image.
A differentiating step; The entire area of the image is subjected to black-and-white compression
Generate black encoded data, and color the color area.
And perform color coding to generate color-coded data
Processing steps; The black-and-white coded data generated by the processing step;
Storage step for storing color encoded data respectively
When, Compatible with other devices that only have the ability to receive black and white encoded data
Transmitting the stored black-and-white coded data,
Has the ability to receive black encoded data and color encoded data
The other black and white coded data stored
And transmitting the color encoded data.
An image transmission method comprising: