JPH07131658A - Image communication equipment - Google Patents

Abstract

PURPOSE:To prevent image information from being omitted and to unnecessitate a reduction circuit for display by decoding a stored progressive compressed code up to any prescribed hierarchy corresponding to the resolution of a display means and the resolution of a stored image. CONSTITUTION:A MODEM 2 is connected to a line through an NCU 3. This equipment is provided with a control part 1, a transmission/reception buffer 4, an image file 5 such as a hard disk or a DRAM, a JBIG encoder/decoder 6 for performing encoding/decoding in the progressive compressing system of JBIG, an encode/decoder 7 for MN, an MR and MMR systems, a video RAM 8 for displaying images on a display 14, an image buffer 9 for extending hierarchical images required for encoding/decoding, a scanner 10 for reading images, and a printer 11 for recording images. Then, the JBIG encoder/decoder 6 decodes the stored code up to the prescribed hierarchy corresponding to the resolution of the display 14 and the resolution of the image stored in the image file 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image communication apparatus and, for example, to a facsimile apparatus capable of displaying a received image or a reserved transmission image on a display device and confirming the entire contents of the image. ..

[0002]

2. Description of the Related Art The resolution used in a normal facsimile device is 203.2 dpi in the main scan and 195.58 dpi in the sub scan in the fine mode of G3 facsimile, and the number of pixels is A.
In 4, the main scan is 1,728 pixels and the sub-scan is 2,287 pixels. Therefore, in order to display the entire one screen of the image on the display, the number of pixels that can be displayed on the display must be reduced. In the case of a high-resolution display of 1,024 x 768 pixels, considering the sub-scanning direction, it will be reduced to 1/3 to display the entire screen.

[0003]

However, the above-mentioned conventional example has the following problems. That is, various methods such as simple thinning out and projection method have been proposed for the image reduction method. However, in the conventional reduction method, when the raw data of the original image is reduced, image information is lost and a thin line is generated. There was a defect that the image disappeared or the pseudo halftone pattern became distorted. Therefore, when displaying a reduced image on a display with a resolution of 100 dpi, it becomes impossible to read the characters, the gray scale of pseudo halftone is disturbed, and a new reduction circuit is provided to display further,
There is a drawback that a frame memory corresponding to the original resolution is required in order to reduce the image once encoded.

On the other hand, recently, a progressive compression method based on JBIG has been proposed, and a method of transmitting an image which is hierarchically encoded and accumulated for each resolution reduced to 1/2 ⁿ has been proposed. Among them, as a PRES processing for 1/2 ⁿ resolution conversion processing, a reduction method with good preservation of fine lines and pseudo intermediate density is proposed.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and has the following structure as one means for solving the above problems. That is, it is provided with a storage unit for storing image data encoded by the progressive compression method, a decoding unit for decoding the code stored in the storage unit, and a display unit for displaying the image decoded by the decoding unit. The decoding means decodes the code stored in the storage means up to a predetermined layer according to the resolution of the display means and the resolution of the image stored in the storage means.

[0006]

According to the above construction, an image communication apparatus for decoding the accumulated progressive compression code to a predetermined layer according to the resolution of the display means and the resolution of the accumulated image and displaying the decoded image is provided. For example, it is possible to prevent loss of image information when reducing raw data of an original image, and to eliminate a reduction circuit for displaying on a display.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image communication apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of the image communication apparatus of this embodiment. In the figure, 2 is a MODEM, which is connected to the line via the NCU 3.
1 is a control unit, 4 is a transmission / reception buffer, 5 is an image file such as a hard disk or DRAM, 6 is a JBIG code decoder which performs code decoding by the JBIG progressive compression method, 7 is MH, MR,
A code decoder for performing MMR code decoding, 8 is a video RAM for displaying an image on the display 14, 9 is an image buffer for expanding a hierarchical image required for code decoding, 1
Reference numeral 0 is a scanner for reading an image, and 11 is a printer for recording an image.

An image bus 12 connects the JBIG code decoder 6, code decoder 7, video RAM 8, image buffer 9, scanner 10, printer 11 and the like. A code and control bus 13 connects the control unit 1, MODEM 2, transmission / reception buffer 4, image file 5, JBIG code decoder 6 and code decoder 7. The detailed operation of these configurations will be described below.

First, the operation of displaying on the display 14 in order to confirm the content of the transmission reserved image will be described. The JBIG encoder / decoder 6 encodes the image data read by the scanner 10 at an arbitrary resolution by a progressive encoding method having an m-layer hierarchical structure determined from the reading resolution and the display resolution. At this time, for example, when the nth layer is encoded, the image data of the nth layer and the image with rough resolution of the (n + 1) th layer are developed in the image buffer 9. When the image read by the scanner 10 is to be encoded in real time, the original image is not expanded in the image buffer 9 and the uppermost layer is encoded according to the data supply speed of the scanner 10.
Here, the original image is the highest layer and the layer with the coarsest resolution is the lowest layer.

The image data encoded by the JBIG encoder / decoder 6 by the progressive compression method is accumulated in the image file 5 and reserved for transmission. When transmitting an image reserved for transmission, the receiving side determines whether or not decoding by the progressive compression method is possible, and if it is possible, the image data encoded by the progressive compression method stored in the image file 5 is transmitted. , The transmission block unit is transferred to the transmission / reception buffer 4, the image data is transferred from the transmission / reception buffer 4 to the MODEM 2, and is sent to the line via the NCU 3.

If the receiving side cannot decode the progressive compression method, the JBIG image data stored in the image file 5 and encoded by the progressive compression method is used.
The data is decoded by the code decoder 6 and coded by the code decoder 7 to perform coding suitable for the receiving side, and then send it to the line through the transmission / reception buffer 4, MODEM2 and NCU3.
Also at this time, for decoding the nth layer, the nth layer is stored in the image buffer 9.
An area for developing the entire image with rough resolution of the hierarchy and the (n + 1) th hierarchy is required, but the highest hierarchy is the JBIG code decoder 6
By combining the raw image data development speed of the above and the encoding processing speed of the encoder / decoder 7, it is not necessary to expand one page of the original image in the image buffer 9.

On the other hand, when the transmission reserved image is displayed on the display 14, the JBIG code decoder 6 sequentially decodes the image data accumulated in the image file 5 and encoded by the progressive compression method up to the nth layer. When displaying an image icon in the multi-window, the decoding is stopped at the lowest resolution layer, and the image data of the lowest resolution layer is transferred from the image buffer 9 to the video RAM 8. At this time, when there are a plurality of images reserved for transmission, the lowest-resolution layer is decoded for each individual code data and displayed together with the management data on the multi-window of the display 14.

Next, when the image displayed as an icon is selected and its contents are to be displayed, the entire image is displayed on the display 14 by decoding up to the nth layer according to the number of display pixels of the display 14 and the resolution of the original image. Is displayed. At this time, raw image data up to the n-th layer is loaded in the image buffer 9. When there is an instruction to enlarge and display a finer portion, the higher order hierarchy is decoded and displayed on the display 14 according to the instruction.

If there is an instruction to confirm the recording,
The image buffer 9 is used to read and decode the code data of the higher hierarchy than the hierarchy decoded up to now from the image file 5, and the printer 11 prints it. Also at this time, if the decoding can be performed in real time according to the print speed, it is not necessary to secure the frame memory of the original image.

Next, the display display of the received image will be described. The code data received via NCU3 is M
After passing through the ODEM 2, the data is once expanded in the transmission / reception buffer 4 for each block. If the code data received at this time is a progressive compression code, it is stored in the image file 5 as it is from the transmission / reception buffer 4, and the communication management file indicating the resolution of the received image is stored in another memory, for example, the control unit 1.
It is stored in RAM etc.

When the received code data is MH, MR or MMR code, the code decoder 7 temporarily expands it into raw image data, and then the JBIG code decoder 6 performs progressive coding to obtain an image. Store in file 5. At this time, a progressive code having a hierarchy up to the optimum resolution for icon display is performed according to the resolution of the received image and the display resolution.

Thereafter, the image data accumulated in the image file 5 is displayed on the display 14 in the same manner as the display of the transmission reserved image described above. FIG. 2 is a flowchart showing an example of a display procedure of the transmission reservation image or the reception image, which is executed by the control unit 1 according to a program stored in the built-in ROM or the like. In the figure, in step S1, the layer number n is set to 1 (the lowest layer), and in step S2 the nth layer is set.
The hierarchy is decoded, and the icon is displayed on the display 14 in step S3.

Subsequently, when the icon is selected in step S4, the layer number n is incremented in step S5, the nth layer is decoded in step S6, and step S6 is executed.
In step 7, the number of pixels of the display 14 is compared with the number of decoded pixels. If the number of decoded pixels is small, the process returns to step S5, and decoding of the higher hierarchy is performed. If the number of pixels of the display 14 or more is decoded, the image decoded in step S8 is displayed on the display 14.

Further, if there is an enlargement instruction in step S9, the process returns to step S5, and the decoding and display of the upper layer is performed. As described above, according to the present embodiment, it is possible to display on the display without adding a new reduction circuit and without a frame memory corresponding to the original resolution, and it is possible to easily store the stored image. Can be confirmed.

The present invention may be applied to either a system composed of a plurality of devices or an apparatus composed of a single device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0021]

As described above, according to the present invention, an image for decoding the accumulated progressive compression code up to a predetermined layer according to the resolution of the display means and the resolution of the accumulated image and displaying the decoded image A communication device can be provided, for example, preventing loss of image information when reducing raw data of an original image,
There is an effect that a reduction circuit for displaying on a display is unnecessary, and further, a frame memory corresponding to an original resolution for performing a reduction process on an image once encoded is also unnecessary.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of an image communication apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an example of a display procedure of a reserved transmission image or a received image according to the present embodiment.

[Explanation of symbols]

 1 Controller 2 MODEM 3 NCU 4 Transmission / Reception Buffer 5 Image File 6 JBIG Code Decoder 7 Code Decoder 8 Video RAM 9 Image Buffer 10 Scanner 11 Printer 12 Image Bus 13 Code and Control Bus 14 Display

Claims (2)

[Claims] 1. A storage unit for storing image data encoded by a progressive compression method, a decoding unit for decoding the code stored in the storage unit, and a display unit for displaying an image decoded by the decoding unit. An image characterized in that the decoding means decodes the code accumulated in the accumulating means up to a predetermined layer according to the resolution of the display means and the resolution of the image accumulated in the accumulating means. Communication device. 2. A receiving means for receiving encoded image data, a second decoding means for decoding an MH, MR or MMR code, and an encoding means for encoding the image data by a progressive compression method. The progressive compression code received by the receiving means is stored in the storage means as it is, and the MH, MR or MMR code received by the receiving means is decoded by the second decoding means, and then the code The image communication apparatus according to claim 1, wherein the image is encoded by an encoding unit and accumulated in the accumulating unit.