JPH05328148A - Picture communication equipment - Google Patents

Abstract

PURPOSE:To attain coding processing corresponding to a designated picture attribute. CONSTITUTION:Multi-value picture data read by an original read section 1 according to a picture attribute designated by a transmission picture attribute designation section 2 are subjected to multi-value coding by a multi-value coding processing section 3 or the multi-value picture data are binarized by a binarizing processing section 4, and the binarized picture data are subjected to binary coding by a binary coding processing section 5.. Coded data from the multi-value coding processing section 3 or the binary coding processing section 5 are fed to a transmission line via a CCU 7 by a multiplexer 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image communication device having a multi-level coding function and a binary coding function.

[0002]

2. Description of the Related Art Conventionally, as a color facsimile apparatus,
There are known two-value encoding and two-value encoding of image data.

In the former method, the multi-valued data of the read image is converted into a binary value by a document reading device such as a CCD, and then binary coded using a coding method such as run length coding for each color component. It will be transformed. On the other hand, the latter
The multi-valued image data that has been read is converted into spatial frequency components by orthogonal transformation such as DCT (discrete cosine transform), and is encoded as it is.

In many multi-level coded color facsimile machines, the image obtained on the receiving side through communication has a good image quality like a photograph, that is, a whole image of a natural color original, and a high compression rate is realized. it can.

On the other hand, a binary coded color facsimile apparatus which converts multi-valued data of a read image into a binary value and then encodes the binary image data like a character original due to its encoding characteristic. Even if expressed, it is suitable for originals with little image quality deterioration, and a high compression rate can be realized.

[0006]

However, the multi-level coded color facsimile apparatus eliminates high-frequency components, which have little visual effect due to its coding characteristics, and
Since the image information is compressed, there is a problem that the image obtained on the receiving side by communication is deteriorated in the case of an image containing many high frequency components such as a text original.

On the other hand, since the binary coded color facsimile apparatus converts multi-valued image data into binary values and performs an encoding process, in the case of a natural image color original, a received image obtained by communication on the receiving side is obtained. Has a problem that the halftone expression is inferior and the image quality is inferior to the received image obtained by the multi-level encoding method.

An object of the present invention is to provide an image communication apparatus which can solve the above problems and can perform an encoding process corresponding to a designated image attribute.

[0009]

In order to achieve such an object, the present invention provides a multi-value encoding means for multi-value encoding multi-valued image data, and a binarization method 2 The multi-value encoding is performed according to any one of a plurality of predetermined image attributes, a binarizing unit, a binarizing unit that binarizes the image data binarized by the binarizing unit, and a plurality of predetermined image attributes. Means or selecting means for selecting coded data from any of the binary coding means.

[0010]

According to the present invention, the code data from either the multi-value coding means or the binary coding means is selected by the selecting means in accordance with the image attribute selected by the selecting means.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. This is an example of a color facsimile machine.

In FIG. 1, reference numeral 1 is a document reading portion, which is C
The original is read by a CD or the like. Reference numeral 2 denotes a transmission image attribute designating section for the operator to designate the image attribute of the transmission image. Reference numeral 3 denotes a multi-value encoding processing unit, which encodes the multi-value data of the image read by the document reading unit 1 as it is in multi-value. A binarization processing unit 4 converts multi-valued data of the image read by the document reading unit 1 into binary data. A binary encoding processing unit 5 encodes the binary image data converted by the binary encoding processing unit 4. A multiplexer 6 selects either the multi-level encoding processing section 3 or the binary encoding processing section 5 according to the image attribute designated by the transmission image attribute designating section 2. A CCU 7 outputs the code data from the multiplexer 6 to the transmission line.

FIG. 2 is a flow chart showing the processing procedure in this embodiment.

The operation waits until the operator designates the image attribute of the document to be transmitted by the transmission image attribute designation section 2, and when the image attribute of the document to be transmitted is designated (S201), the encoding process is started. Then, based on the set image attribute, it is determined whether or not the binary encoding process is performed (S202).

If the result of determination is binary encoding processing, reading of the original is started (S203), and the read multivalued image data is converted into binary by the binary processing unit 4 (S204). Binary encoding processing is performed by the binary encoding processing unit 5 on all the read image data (S205,
S206). Then, the transmission process is started, and the code data is output to the communication transmission line via the CCU 7 (S210).

On the other hand, as a result of the determination, when the encoding process corresponding to the set image attribute is the multi-level encoding process,
As in the case of the binary encoding process, the document is read (S2
07), the multi-valued encoding processing unit 3 encodes the read multi-valued image data as it is in multi-valued form (S208, S209). Then, the transmission process is started, and the code data is output to the communication transmission line via the CCU 7 (S210).

In the case of multi-level encoding processing, the binarization processing unit 4
And the binary encoding processing unit 5 is not operated. This is because the encoding process of the color facsimile apparatus only performs the encoding process corresponding to the image attribute set by the operator.
This is because the steps 203 to S206 and the steps S207 to S209 are not performed at the same time.

As described above, in the present embodiment, a multi-valued encoding method capable of encoding a natural image color image such as a photograph with a high compression rate and high image quality, or read multi-valued image data is used. After converting to binary, specify either binary encoding method that can encode with high compression rate and high image quality for images with little deterioration in image quality even when expressed in binary such as characters An appropriate selection can be made according to the created image attribute.

[0020]

As described above, according to the present invention,
Depending on the selected image attribute, the multi-level encoding means or 2
Since any one of the coded data of the value coding means is selected, there is an effect that the coding process corresponding to the designated image attribute can be performed.

[Brief description of drawings]

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

FIG. 2 is a flowchart showing a processing procedure in one embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Original reading unit 2 Transmission image attribute designating unit 3 Multi-level encoding processing unit 4 Binarization processing unit 5 Binary encoding processing unit 6 Multiplexer 7 CCU

Claims (1)

[Claims] 1. A multi-value encoding means for multi-value encoding multi-valued image data, a binarizing means for binarizing the multi-valued image data, and an image binarized by the binarizing means. Binary encoding means for binary encoding the data, and code data from either the multi-level encoding means or the binary encoding means depending on any of a plurality of predetermined image attributes. An image communication apparatus comprising: a selection unit for selecting.