JPH077621A - Picture transmitter - Google Patents

Abstract

PURPOSE:To transmit data to an opposite machine different in an encoding system without trouble. CONSTITUTION:Original picture data are encoded in a black/white encoding circuit 26 which an operator designates, a JBIG encoding circuit 28,,3 JPEG DCT base line encoding circuit 30 or a JPEG DCT extension encoding circuit 32 and it is encoded in a JPEG spatial encoding circuit 34 being a reversible encoding system at the time of reading an original. Two kinds of encoding data are accumulated in a hard disk device 40. When the selected circuits 26, 28, 30 or 32 are not compatible to the reception capacity of the opposite machine, the code output of the circuit 34, which is stored in the hard disk device 40, is decoded in a decoding circuit 48. Then, data are converted into resolution which the opposite machine requests in a picture element density conversion circuit 16. Then, encoding is executed in the circuits 26, 28, 30 or 32 which the opposite machine requests, and data are outputted from a communication control circuit 42 to a communication line 44.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmitting apparatus having a monochrome image transmitting function and a color image transmitting function.

[0002]

2. Description of the Related Art An image transmitting apparatus having various encoding means for transmitting a black and white image and a color image and capable of selecting an encoding method is well known. The MMR, MR, or MH method is known as an encoding method for transmitting a monochrome image. As a coding method for transmitting a color image, a JPEG method is known as a multilevel coding method and a JBIG method is known as a binary coding method. The JPEG method further includes a lossless encoding DCT method (baseline method and extended method) and a lossless encoding spatial method.

In the conventional example having such plural kinds of encoding means, for example, an original image is encoded by the encoding means selected on the transmitting side and temporarily stored in a hard disk device or the like. Then, call the transmission partner, confirm the agreement of resolution, color space, encoding method, etc. by negotiation with the receiving terminal, and if they agree, transmit the encoded data of the hard disk device, and the agreement must be made. If so, the transmission is interrupted.

In addition, the original image is used as raw data in the hardware.
It is stored in a disk device etc. and called before encoding.
First, negotiation with the transmission partner is performed to set the resolution,
There is also a method in which, after confirming the color space and the encoding method, the raw data is encoded with matching parameters and transmitted.

Further, the original image is temporarily encoded with a specific resolution, color space and encoding method before calling, and the capability of the receiving terminal is confirmed by calling and negotiation.
When the above-mentioned coding method is suitable, the data is transmitted as it is, but when it is not suitable, the coded data is decoded, and the data is coded by the matched coding method or the like and transmitted.

[0006]

However, in the first conventional example, it is very troublesome to read the original image again when the transmission fails. That is, it is necessary to specify an appropriate code circuit and read the original image again with the image scanner.

In the second conventional example, it is necessary to prepare a large-capacity storage device for storing a large amount of raw data, which is expensive and inefficient.

In the third conventional example, the coding method used initially is not always the reversible method. If the coding method is the irreversible method, the picture quality is deteriorated by the decoding and re-coding. If the other device has only the color reception capability in the case of encoding with the black and white encoding method, it is necessary to start reading the original document again.

An object of the present invention is to provide an image transmitting apparatus that does not have such inconvenience.

[0010]

An image transmitting apparatus according to a first aspect of the present invention is a color image inputting unit, and an image coding unit capable of coping with one or more coding systems for coding image information.
A lossless encoding unit that losslessly encodes image information, a storage unit that stores the image encoding unit and an output code of the lossless encoding unit, a lossless decoding unit that corresponds to the lossless encoding unit, and the color. At least when the document is read by the image input means, the coded data by the reversible encoding means is stored in the storage means, and the reversible decoding means and the image encoding means use the encoding method or the like that meets the request of the other machine by negotiation. And a control means for re-encoding and transmitting.

[0011]

With the above means, the original image is compressed and stored by the reversible encoding method at the time of reading the original, and if necessary, the original image is decoded and re-encoded in the color space, the resolution, the encoding method and the like requested by the other device and transmitted. Therefore, it is not necessary to read the original again. Since the original image is compressed and stored in the storage means by the reversible encoding method, the storage capacity is smaller than that of storing raw data. In addition, even if decoding and re-encoding, there is little deterioration in image quality.

[0012]

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

FIG. 1 shows a schematic block diagram of an embodiment of the present invention. In the present embodiment, when the capability of the communication partner does not match, the previously encoded image data is once decoded and further encoded at a resolution suitable for the communication partner. In preparation for this decoding and re-encoding, in the initial stage, the original image is encoded by the JPEG spatial encoding method, which is a reversible encoding method, and stored in a hard disk device or the like.

In FIG. 1, reference numeral 10 denotes a color scanner which reads an original image with a line sensor or the like and serially outputs the color pixel signals in a dot-sequential RGBX format. As is well known, R is red, G is green, and B is blue. X is undetermined data for inserting black (Bk) described later.

Reference numeral 12 is an interface of the color scanner 10, reference numeral 14 is a γ conversion circuit for γ converting the output of the interface 12 to correct the characteristics of the scanner 10, 16
Is a pixel density conversion circuit that scales the output of the γ conversion circuit 14 or the decoded output for re-encoding to convert the resolution.
Is an image buffer that temporarily stores the multi-valued color image data output from the pixel density conversion circuit 16 in block units.

Reference numeral 20 denotes a black generation circuit for multiply-multiplying the multivalued RGBX data read from the image buffer 18 to generate Bk (black) data, and inserts it at the X position. Reference numeral 22 denotes an output of the black generation circuit 20. A binarizing circuit for binarizing, 24 is a binary image buffer for temporarily storing the output of the binarizing circuit 22 in block units, and 26 is MMR, MR for the binary image data read from the binary image buffer 24. Alternatively, a black-and-white encoding circuit for encoding by the MH system, 28 is a JBIG encoding circuit for encoding the binary image data read from the binary image buffer 24 by the JBIG system.

Further, 30 is a DCT baseline encoding circuit for encoding the multi-valued color image data read from the image buffer 18 by the JPEG DCT baseline method, and 32 is read from the image buffer 18. An encoding circuit that encodes multi-valued color image data by the JPEG DCT extension method, 34 is a spatial encoding circuit that encodes the multi-valued color image data read from the image buffer 18 by the JPEG spatial method, 36 Is a code buffer for temporarily storing the output code of the spatial encoding circuit 34, and 38 is a code buffer for temporarily storing the output code of the encoding circuits 26, 28, 30, 32.

Reference numeral 40 denotes a hard disk device which stores and stores the code data temporarily stored in the code buffers 36 and 38 in preparation for transmission and also stores and stores the received code data. 42 is a communication control circuit (CC) for controlling communication via a communication line 44 such as ISDN, PSTN and a dedicated line.
U), the transmission code data stored in the hard disk device 40 or the transmission code data from the code buffer 38 is output to the communication line 44, and the code data input from the communication line 44 is output to the hard disk device 40. Write in.

Reference numeral 46 designates the hard disk drive 4 for first decoding the coded data due to incompatibility with the receiving side.
A decoding code buffer for temporarily storing the code data read from 0, and a spatial decoding circuit 48 for decoding the output of the decoding code buffer 46. The output of the spatial decoding circuit 48 is fed back to the pixel density conversion circuit 16.

Next, the operation of this embodiment will be described. 2,
FIG. 3, FIG. 4 and FIG. 5 show an operation flowchart of this embodiment as a whole. 6, 7 and 8 show the scanner 1
The timing of RGBX data output from 0 and the timing of black insertion and parallelization are shown.

First, the image processing parameters are set and the scanner 10 is activated (S1). This allows the scanner 1
0, as shown in FIG. 6, serially outputs the read data of the original image in the RGBX format. VE is the scanner 10
Control signals, CK1, CK2, CK4, which indicate the validity of the output of
Is the clock. The output of the scanner 10 is input to the γ conversion circuit 14 via the interface 12 and is γ converted. The pixel density conversion circuit 16 scales the output of the γ conversion circuit 14 by a designated scale factor and converts it into a designated resolution. The output of the pixel density conversion circuit 16 is temporarily stored in the image buffer 18.

Depending on which encoding method is designated by the operator, the encoding by the designated encoding method is started, and at the same time, the encoding by the spatial encoding is started in preparation for re-encoding. That is, binary coding (black and white coding or JB
In the case of IG encoding) (S2), DMA transfer of the data stored in the image buffer 18 to the black generation circuit 20 is started (S3).

As shown in FIG. 7, the black generation circuit 20 generates black data from the RGBX data by the pixel density conversion circuit 16, outputs the RGBBk data, and the binarization circuit 22.
Binarizes the output data of the black generation circuit 20. The output of the binarization circuit 22 is serial-parallel converted as shown in FIG. 8 and stored in the image buffer 24 for one block.

When the designated encoding method is the JBIG method (S4), the JBIG encoding circuit 28 is activated, the binary RGB data of the image buffer 24 is read out, and the JBI is read.
G coding is used (S5), and black and white coding is used (S5).
4), activate the black-and-white encoding circuit 26, and
The Bk data of is read and encoded by the MMR, MR or MH system (S6). The coded data by the coding circuit 26 or 28 is written in the code buffer 38, and when the code buffer 38 is full, it is transferred from the code buffer 38 to the hard disk device 40.

The coding method set by the operator is JPE.
In the case of G method DCT baseline method (S7), DC
The T baseline encoding circuit 30 is activated, the multi-valued RGB data in the image buffer 18 is read out, and JPEG DCT is performed.
It is encoded by the baseline method (S8). If the encoding method set by the operator is the JPEG DCT extension method (S9), the DCT extension encoding circuit 32 is activated, the multi-valued RGB data in the image buffer 18 is read, and the JPEG DCT extension method is used. (S10). The code data coded by the coding circuits 30 and 32 is stored in the hard disk device 40 via the code buffer 38.

Regardless of whether the encoding system set by the operator is the spatial encoding system or not, the spatial encoding circuit 34 is activated and the multivalued R of the image buffer 18 is activated.
The GB data is read and spatially encoded (S1
1). The code data output from the spatial encoding circuit 30 is stored in the hard disk device 40 via the code buffer 36.

Waiting for the end of the encoding process of the image data of one block stored in the image buffer 18 (S1
2) The next block is similarly processed until one page is completed (S13).

In this way, the hard disk device 4
In 0, when the encoding method specified by the operator of the transmitting terminal is the spatial encoding method, the code data by the spatial encoding circuit 34 is accumulated for each block of each page of the document, and the operator of the transmitting terminal specifies If the encoding method to be used is other than the spatial encoding method, the code data and the spatial encoding circuit 3 according to the encoding method specified for each block of each page of the document.
Both of the code data of 4 are stored.

After the encoding is completed, a call is made to the other party designated by the operator (S15) and the line is connected (S1).
6), negotiation is executed (S17). As a result of the negotiation, if the receiving terminal has a receiving capability that matches the transmission parameters (for example, the encoding method, the resolution, the color space, the presence or absence of the table, etc.) in the encoding of S1 to S14 (S18), the hard disk device The code data (code data by spatial coding or code data by another coding method) previously stored in 40 is transferred to the communication control circuit 42 (S19), and the communication control circuit 42 is transferred.
Sends code data to the transmission path connected to the communication partner (S20). S19 and S20 are repeated until the code data of all pages of the document are sent to the transmission path (S21).

When the code data of all pages of the original is sent to the transmission path (S21), the line is disconnected and the transmission is ended (S22).

As a result of the negotiation, if the receiving capability of the receiving terminal does not match the transmission parameters in the encoding in S1 to S14 (S18), it is checked whether or not the automatic re-encoding is set in the transmitting terminal (S23). For example, the user setting switch allows the operator to preset whether or not to automatically re-encode. FIG. 9 shows a setting screen of the user setting switch.

When the user setting switch is set not to automatically re-encode, that is, the automatic re-encoding is set to O.
When in FF, as shown in FIG. 10, a screen prompting re-encoding is displayed on an operation display panel (not shown) (S
24). Waiting for the operator's key input (S25), if there is a key input instructing re-encoding (S26),
The routine proceeds to the routine for automatic re-encoding (S27 and subsequent steps), and for other key inputs, the line is disconnected and the processing ends (S22).

If the automatic re-encoding is not set,
Since it is necessary to wait for the key input by the operator of the transmitting terminal while the line is connected, it is necessary to secure the line. On the other hand, if the automatic re-encoding is not set, the transmission failure is displayed, the line is disconnected, and the transmission operation is ended. At this stage, the hard disk drive 4
It may be possible to select whether to re-encode the spatially-encoded code still stored in 0 or to re-read and transmit the original. In either case, it goes without saying that when transmitting to the same partner, the information on the reception capability of the partner device, which is known in the negotiation (S17), is used.

When automatic re-encoding is performed by a user setting switch (S23) or by an operator key input (S26), the spatial decoding circuit 48 is activated and the spatial encoding stored in the hard disk device 40 is encoded. The decoding of the code, the coding with the transmission parameter suitable for the capability of the receiving terminal, and the transmission to the transmission line are executed.

That is, the spatial coded code stored in the hard disk device 40 is read out, applied to the spatial decoding circuit 48 via the code buffer 46, and decoded. When the decoding for one block is completed (S28), the transmission parameter suitable for the capability of the receiving terminal is set in the related circuit (S29). The decoded image data is accumulated in the image buffer 18 via the pixel density conversion circuit 16.

When the encoding method that can be received by the partner device is binary encoding (black and white encoding or JBIG encoding) (S3
0), a black generation circuit 20 for storing data in the image buffer 18
The DMA transfer to is started (S31). As shown in FIG. 7, the black generation circuit 20 generates black data from the RGBX data by the pixel density conversion circuit 16 and outputs RGBBk data, and the binarization circuit 22 binarizes the output data of the black generation circuit 20. Turn into. The output of the binarization circuit 22 is serial-parallel converted as shown in FIG. 8 and stored in the image buffer 24 for one block.

JBIG is the encoding method that the receiving device can receive.
In the case of the system (S32), the JBIG encoding circuit 28 is activated, the binary RGB data of the image buffer 24 is read and encoded in the JBIG system (S33), and in the case of the monochrome encoding system (S32), the monochrome encoding circuit. 26 is started, the Bk data in the image buffer 24 is read out, and encoded by the MMR, MR or MH system (S34).

The encoding method that can be received by the other device is JPEG
In case of DCT baseline method (S35), DC
The T baseline encoding circuit 30 is activated, the multi-valued RGB data in the image buffer 18 is read out, and JPEG DCT is performed.
It is encoded by the baseline method (S37). Also, JP
In the case of the DCT extension method of the EG method (S37), the DCT extension encoding circuit 32 is activated, and the multivalued R of the image buffer 18
The GB data is read and encoded by the JPEG DCT extension method (S38).

If the encoding circuit of the encoding system that can be received by the other device is not provided (S37), the line is disconnected and the process is terminated (S22).

Waiting for the end of the encoding of one block (S39), the code data encoded by the encoding circuit 26, 28, 30 or 32 is applied to the communication control circuit 42 via the code buffer 38. Then, the communication control circuit 42 sends the code data to the transmission path connected to the communication partner (S4).
1). If the code data for one block is transmitted (S
42) The processing after S27 (decoding, encoding, and transmission) is repeated in block units until one page is transmitted (S43), and further after S27, all pages of the document are transmitted. The process is repeated (S44).

After transmitting all pages of the manuscript (S44),
The line is disconnected and the process ends (S22).

In the above embodiment, various parameters are repeatedly set in the process of re-encoding in block units as shown in S29. However, when the parameter value is constant in block units, re-encoding is performed. Of course, various parameters may be set as preprocessing.

In the above embodiment, the reversible coding method and the irreversible coding compression code are stored in the hard disk device at the document reading stage. The encoding method and the like used for transmission may be determined by negotiation with the partner device. That is, the coded data of the lossless coding method is decoded and re-encoded by the coding method determined by the negotiation,
Send to the other device.

In addition to RGB, the expression format of a color image is
There are YIQ and YCrCb, but needless to say, these may be used.

[0045]

As can be easily understood from the above description, according to the present invention, an original image can be transmitted in a color space, a resolution, an encoding system and the like corresponding to the partner without resetting the original. . Since the original image is compressed and stored by the reversible encoding method, the storage capacity is smaller than that of the raw data. Further, there is an effect that the image quality is less deteriorated even if the decoding and the re-encoding are performed.

[Brief description of drawings]

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

FIG. 2 is a part of an operation flowchart of the present embodiment.

FIG. 3 is a part of an operation flowchart of the present embodiment.

FIG. 4 is a part of an operation flowchart of the present embodiment.

FIG. 5 is a part of an operation flowchart of the present embodiment.

FIG. 6 is a timing chart of the output of the scanner 10.

FIG. 7 is a timing chart of the output of the black generation circuit 20.

FIG. 8 is a timing diagram of serial-parallel conversion.

FIG. 9 is an example of a setting screen of a user setting switch.

FIG. 10 is an example of a display screen during transmission.

[Explanation of symbols]

10: Color Scanner 12: Interface 1
4: γ conversion circuit 16: Pixel density conversion circuit 18: Multi-valued color image buffer 20: Black generation circuit 22: Binary circuit 24: Binary image buffer 26: Monochrome coding circuit 28: JBIG coding circuit 30: DCT Baseline coding circuit 32: DCT extension coding circuit 34: Spatial coding circuit 36, 38: Code buffer 4
0: Hard disk device 42: Communication control circuit (CC
U) 44: Communication line 46: Code buffer 48: Spatial decoding circuit

Claims (5)

[Claims] 1. A color image input means, an image encoding means for encoding one or more encoding methods for encoding image information, a lossless encoding means for losslessly encoding image information, and the image encoding method. Means and a storage means for storing the output code of the lossless encoding means, a lossless decoding means corresponding to the lossless encoding means, and at least code data by the lossless encoding means at the time of reading the original by the color image input means. An image characterized by having a control means for storing in the storage means, re-encoding by the lossless decoding means and the image encoding means by a coding method or the like that meets the request of the partner device by negotiation Transmitter. 2. The image transmitting apparatus according to claim 1, wherein the lossless encoding means is JPEG lossless encoding means. 3. The selecting device according to claim 1 or 2, further comprising: selecting means for selecting and instructing automation or manualization of the transmission by the re-encoding.
The image transmission device according to 1. 4. When reading a document, code data by the image coding means is also stored in the storage means, and the control means re-encodes when the code data by the image coding means is compatible with the other device. The image transmitting apparatus according to claim 1, 2 or 3, wherein the code data by the image encoding means is transmitted to the other device without being transmitted. 5. The control means outputs the output code of the lossless encoding means stored in the storage means to the lossless decoding means and the image encoding means in response to the transmission to the same partner device that has failed in transmission. 5. The image transmitting apparatus according to claim 1, wherein the image is transmitted after being re-encoded by an encoding method or the like that meets the request of the other device due to negotiation when transmission fails.