JPH10341344A - Facsimile equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the frequency of memory-full states in an image memory by storing image data in an image memory through high compression while using lossy type comprising system, when the empty capacitance of image memory becomes less than a prescribed value. SOLUTION: An operator inputs the destination from a control panel and stores the image data of original into the image memory but at such a time, the current empty capacitance of image memory is confirmed. When the empty capacitance is more than a prescribed value p, an encoder circuit selects a selector 22 so as to perform a losses type compression, and image data are stored through the selector 22 into the image memory after compression at a lossless type encoder circuit 23. When the empty capacitance of image memory is less than the prescribed value, the selector 22 is selected so as to perform the lossy type compression. The image data are transferred via the selector 22 into the image memory, while being compressed by the lossy encoder circuit 23 after reducing the amount of raw image data and while first referring to the bit map or the like of image data at the lossy encoder circuit 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus which can efficiently use an image memory.

[0002]

2. Description of the Related Art FIG. 1 is a block diagram showing a conventional facsimile apparatus. In FIG.
A reading unit for reading the contents of an original such as an IS,
Reference numeral 2 denotes a read image processing circuit for processing a signal such as image data from the reading unit 1, reference numeral 3 denotes an encoding circuit for encoding and compressing the image data read and processed by the read image processing circuit 2, and reference numeral 4 denotes transmission and An image memory for temporarily storing received image data. Reference numeral 5 denotes a decoding circuit for decoding and expanding encoded image data stored in the image memory 4, and reference numeral 6 denotes a decoding circuit 5.
A recording image processing circuit for performing image processing on image data decompressed by the recording unit 7 as an output device, 7
Reference numeral denotes a recording unit such as a laser printer or a thermal head for recording image data processed by the recording image processing circuit 6 on recording paper.

[0003] Reference numeral 8 denotes an NC having a telephone line interface.
A U circuit 9, a modem for modulating and demodulating, 10 a decoding circuit for decoding and expanding image data from the modem 9 or coded image data stored in the image memory 4, and 11 a decoding circuit 10 A resolution conversion circuit that performs resolution conversion of the decoded image data in accordance with a communication partner device at the time of transmission, or simply passes image data, and 12 encodes the image data whose resolution has been converted by the resolution conversion circuit 11. This is an encoding circuit that encodes and compresses the image data and outputs the same to the modem 9 or encodes and compresses the image data that has passed through the resolution conversion circuit 11 and stores it in the image memory 4. 13 is a C for controlling the above circuits.
PU, 14 is a drive system such as a motor and a cutter, 15
Denotes an operation panel such as an LCD and keys. FIG.
In this example, two circuits are provided as in the encoding circuits 3 and 12 and the decoding circuits 5 and 10, but one circuit may be provided in each case.

Next, the operation will be described. When transmitting image data, first, the reading unit 1 reads the written contents of the document, and the reading image processing circuit 2 performs signal processing such as converting analog image data from the reading unit 1 into digital image data. . The encoding circuit 3 encodes and compresses the image data read and processed by the read image processing circuit 2 and temporarily stores the image data in the image memory 4. Here, since the data amount is usually too large for the image memory 4 to be stored in the image memory 4 and the image data 4 cannot be effectively used, the image data is compressed by various encoding methods. As a compression method, MH (Modified H) does not cause loss during decoding.
uffman), MR (Modified Rea)
d), MMR (Modified MR), JBIG
(Joint Bi-level Image Expo
rts Group).

Next, according to the availability of the telephone line connected to the NCU circuit 8 and the priority of the image data stored in the image memory 4, the operation shifts to the actual transmission operation. After the telephone line is connected by the NCU circuit 8, the encoded image data stored in the image memory 4 is decoded and expanded by the decoding circuit 10, and is decoded by the decoding circuit 10 by the resolution conversion circuit 11. The resolution conversion is performed on the image data according to the communication partner device. The encoding circuit 12 encodes and compresses the image data whose resolution has been converted by the resolution conversion circuit 11 and outputs the image data to the modem 9. Modem 9
Then, the image data encoded by the encoding circuit 12 is modulated and transmitted from the NCU circuit 8 to the communication partner device via the telephone line.

At the time of receiving image data, a signal is received from an NCU circuit 8 from a communication partner via a telephone line, and the received signal is demodulated by a modem 9 to be decoded.
Output to 0. The decoding circuit 10 decodes and decompresses the image data, and outputs the image data to the encoding circuit 12 simply through the resolution conversion circuit 11. The encoding circuit 12 encodes and compresses the image data and temporarily stores it in the image memory 4. Further, the image data stored in the image memory 4 is extracted by the decoding circuit 5 according to the priority order, decoded and expanded, and the expanded image data is output by the recording image processing circuit 6 to the recording unit 7 as an output device. After the image processing, the recording unit 7 records the image on recording paper.

[0007]

Since the conventional facsimile apparatus is configured as described above, the image memory 4 is used when transmitting and receiving image data. In this case, the facsimile apparatus cannot be used, and there is a problem that the usability is poor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to obtain a facsimile apparatus which reduces the frequency of occurrence of memory full in an image memory.

[0009]

According to a first aspect of the present invention, there is provided a facsimile apparatus which stores image data to be stored by using a lossy compression method when a free space of an image memory becomes smaller than a predetermined value. It is provided with a lossy encoding circuit that highly compresses and stores it in the image memory.

In the facsimile apparatus according to the present invention, when the free space of the image memory becomes smaller than a predetermined value, the image data read by the reading unit is highly compressed by using a lossy compression method. A lossy type encoding circuit and, when the free space of the image memory is equal to or more than a predetermined value, the image data read by the reading unit, and when the free space of the image memory becomes less than the predetermined value, the lossy type coding circuit. A lossless encoding circuit for compressing the image data highly compressed by the encoding circuit using a lossless compression method and storing the compressed image data in an image memory.

According to a third aspect of the present invention, in the facsimile apparatus, when the free space of the image memory becomes less than a predetermined value, the image data received via the communication line from the network control circuit is compressed by a lossy compression method. A high-compression lossy encoding circuit, and, when the free space of the image memory is equal to or more than a predetermined value, the image data received via the communication line from the network control circuit, and the free space of the image memory. And a lossless encoding circuit for compressing the image data highly compressed by the lossy encoding circuit using a lossless compression method and storing the image data in an image memory when is less than a predetermined value. It is.

According to a fourth aspect of the present invention, when the free space of the image memory becomes smaller than a predetermined value, the facsimile apparatus converts the image data received from the local area network interface via the local area network into a lossy type. A lossy encoding circuit that performs high compression using a compression method, and, when the available space of the image memory is equal to or more than a predetermined value, image data received from the local area network interface via the local area network, A lossless encoding circuit that compresses the image data highly compressed by the lossy encoding circuit using a lossless compression method when the free space of the memory becomes less than a predetermined value, and stores the compressed data in the image memory; It is provided with.

A facsimile apparatus according to a fifth aspect of the present invention provides a facsimile apparatus, wherein a decoding circuit extracts and decodes image data stored in an image memory when a free space of the image memory becomes less than a predetermined value; A lossy type encoding circuit that highly compresses the image data extracted by the decoding circuit using a lossy type compression method, and a lossless type compression method of the image data highly compressed by the lossy type encoding circuit. And a lossless encoding circuit for compressing the data and storing it in an image memory.

According to a sixth aspect of the present invention, there is provided a facsimile apparatus, wherein an operation panel for selecting whether or not to perform lossy compression, and a lossy type encoding circuit for processing image data in accordance with the selection of the operation panel. It is provided with.

In the facsimile apparatus according to the present invention, when a failure occurs in the recording unit or when the recording paper runs out, the image data is forcibly compressed by using a lossy compression method. Provided with a lossy type encoding circuit.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a block diagram showing a facsimile apparatus according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a reading unit for reading written contents of an original such as a CCD or CIS, and 2 denotes image data from a reading unit 1 and the like. A read image processing circuit for processing signals of
Reference numeral 3 denotes an encoding circuit for encoding and compressing the image data read and processed by the read image processing circuit 2, and reference numeral 4 denotes an image memory for temporarily storing transmitted and received image data. Reference numeral 5 denotes a decoding circuit for decoding and expanding the encoded image data stored in the image memory 4, and 6 denotes an image data expanded by the decoding circuit 5 according to a recording unit 7 which is an output device. A recording image processing circuit 7 for performing the processing is a recording unit such as a laser printer or a thermal head for recording the image data subjected to the image processing by the recording image processing circuit 6 on recording paper.

Reference numeral 8 denotes an NC having a telephone line interface
U circuit (network control circuit), 9 is a modem that performs modulation and demodulation, 10
A decoding circuit decodes and expands the image data from the modem 9 or the coded image data stored in the image memory 4, and 11 communicates the image data decoded by the decoding circuit 10 at the time of transmission. Whether the resolution conversion is performed in accordance with the partner device, or the resolution conversion circuit 12 that simply passes the image data encodes and compresses the image data whose resolution has been converted by the resolution conversion circuit 11 and outputs the encoded data to the modem 9. Or an encoding circuit that encodes and compresses the image data that has passed through the resolution conversion circuit 11 and stores it in the image memory 4. 13 is a CPU for controlling the above circuits, 14 is a drive system such as a motor and a cutter, and 15 is an operation panel such as an LCD and keys.
Although two circuits are provided in FIG. 1 like the encoding circuits 3 and 12 and the decoding circuits 5 and 10, they may be provided one by one.

FIG. 2 is a block diagram showing an encoding circuit according to the first embodiment of the present invention. In FIG. 2, reference numeral 21 denotes an image data read and processed by the read image processing circuit 2 and encoded. A lossy encoding circuit that performs high compression using a lossy compression method,
2 bypasses the lossy type encoding circuit 21 when the free space of the image memory 4 is equal to or more than the predetermined value, and switches the lossy type coding circuit 21 when the free space of the image memory 4 becomes less than the predetermined value. Selector, 23 is selector 2
2 is a lossless encoding circuit that compresses image data input through the image memory 2 using a lossless compression method and stores the data in the image memory 4.

Next, the operation will be described. When transmitting image data, first, the reading unit 1 reads the written contents of the document, and the reading image processing circuit 2 performs signal processing such as converting analog image data from the reading unit 1 into digital image data. . The encoding circuit 3 encodes and compresses the image data read and processed by the read image processing circuit 2 and temporarily stores the image data in the image memory 4. Here, since the data amount is usually too large for the image memory 4 to be stored in the image memory 4 and the image data 4 cannot be effectively used, the image data is compressed by various encoding methods.

Next, according to the availability of the telephone line connected to the NCU circuit 8 and the priority order of the image data stored in the image memory 4, the operation shifts to the actual transmission operation. After the telephone line is connected by the NCU circuit 8, the encoded image data stored in the image memory 4 is decoded and expanded by the decoding circuit 5, and is decoded by the decoding circuit 10 by the resolution conversion circuit 11. The resolution conversion is performed on the image data according to the communication partner device. The encoding circuit 12 encodes and compresses the image data whose resolution has been converted by the resolution conversion circuit 11 and outputs the image data to the modem 9. The modem 9 modulates the image data encoded by the encoding circuit 12 and transmits the modulated image data from the NCU circuit 8 to a communication partner via a telephone line.

When receiving image data, a signal is received from an NCU circuit 8 from a communication partner via a telephone line, and the received signal is demodulated by a modem 9 to be decoded by a decoding circuit 1.
Output to 0. The decoding circuit 10 decodes and decompresses the image data, and outputs the image data to the encoding circuit 12 simply through the resolution conversion circuit 11. The encoding circuit 12 encodes and compresses the image data and temporarily stores it in the image memory 4. Further, the image data stored in the image memory 4 is extracted by the decoding circuit 5 according to the priority order, decoded and expanded, and the expanded image data is output by the recording image processing circuit 6 to the recording unit 7 as an output device. Recording unit 7 after image processing according to
Is recorded on recording paper.

Here, the lossy compression method will be briefly described. In the current facsimile apparatus, when compressing image data, the decompressed image data is the same reversible compression method as the image data before 100% compression unless there is a transmission error or the like, and is represented by the MH and MR methods and the like. It is called a lossless compression method. On the other hand, a compression method using visual characteristics used in ordinary broadcast images and the like is an irreversible compression method and is called a lossy compression method. The lossy type compression method has a distortion in a small range, but the compression efficiency is correspondingly higher than that of the lossless type.

FIG. 3 is a flow chart showing the operation of the encoding circuit which is a feature of the first embodiment. In FIGS. 3 and 2, the operator inputs a destination from the operation panel 15 and outputs the image data of the original. The image data is stored in the image memory 4. At this time, the current free space of the image memory 4 is checked (step ST1). If the free space is equal to or larger than a predetermined value (step ST2), the encoding circuit 3 sets the lossless type. , And the image data is compressed by the lossless encoding circuit 23 via the selector 22 (step ST3) and stored in the image memory 4.

In step ST2, when the free space of the image memory 4 is smaller than a predetermined value, the selector 22 is selected so as to perform lossy compression. Therefore, the image data is first reduced in the lossy encoding circuit 23 by referring to a bit map of the image data in the lossy encoding circuit 21 (step ST4), and then the lossless encoding circuit 23 is transmitted through the selector 22. (Step ST
3) Transfer to the image memory 4. Furthermore, the size of the compressed image data is detected (step ST5), and the free space of the image memory 4 is corrected (steps ST6 and ST).
7).

The image memory 4 finally stores lossless compressed image data in the lossless encoding circuit 23. Therefore, when transmitting the image data recorded in the image memory 4, the decoding circuit 10 decodes and expands the image data recorded in the image memory 4, and further encodes the image data by the encoding circuit 12. When the image data is expanded and compressed by the conventional lossless decoding circuit 10 and lossless encoding circuit 12, the same image data as the image data after high compression by the lossy encoding circuit 21 can be obtained. can get. When reading the image data stored in the image memory 4 by the decoding circuit 10, the size of the read image data is detected (step ST8), and the free space of the image memory 4 is corrected (step ST8). Steps ST6 and ST7).

As described above, according to the first embodiment, when the image data of the document read by the reading unit 1 is stored in the image memory 4, when the free space of the image memory 4 is less than the predetermined value. The selector 22 is switched to compress the image data in a lossy manner before the image memory 4
Since the image data read by the reading unit 1 is stored in the image memory 4, the frequency of occurrence of memory full of the image memory 4 can be reduced.

Embodiment 2 FIG. In the first embodiment, as shown in FIG. 2, the encoding circuit 3 includes a lossy encoding circuit 21, a selector 22, and a lossless encoding circuit 23.
However, in the second embodiment, the encoding circuit shown in FIG. 2 is applied to the encoding circuit 12.

Next, the operation will be described. When receiving image data, the NCU from the communication partner
The signal is received from the circuit 8, and the received signal is demodulated by the modem 9 and output to the decoding circuit 10. The decoding circuit 10 decodes and expands the image data,
The data is simply passed through the resolution conversion circuit 11 and output to the encoding circuit 12. The encoding circuit 12 encodes and compresses the decoded image data and stores it in the image memory 4. At this time, the current free space of the image memory 4 is checked, and the free space is set to a predetermined value. If above, the encoding circuit 1
2 selects the selector 22 so as to perform lossless type compression, and stores the image data in the image memory 4 after being compressed by the lossless type encoding circuit 23 via the selector 22.

When the free space of the image memory 4 is smaller than a predetermined value, the selector 22 performs lossy compression.
Select Therefore, the image data is first reduced by the lossy encoding circuit 21 while referring to the bit map of the image data, etc.
The data is compressed by the lossless encoding circuit 23 through the second memory 2 and stored in the image memory 4.

As described above, according to the second embodiment, when the image data received from the NCU circuit 8 from the communication partner via the telephone line is stored in the image memory 4, the image memory 4 is free. When the capacity is less than the predetermined value, the selector 22 is switched to compress the image data in a lossy manner before storing the image data in the image memory 4. Therefore, the image data is received from the NCU circuit 8 via the telephone line from the communication partner. It is possible to reduce the frequency of occurrence of memory full in the image memory 4 when storing the image data in the image memory 4. In the second embodiment, the lossy compression is performed only on the image data received from the NCU circuit 8 from the communication partner via the telephone line. However, when transmitting the image data to the communication partner, the lossy compression is performed. The data may be transmitted after the compression of the pattern. In this case, the frequency of occurrence of memory full in the image memory 4 of the communication partner device can be reduced.

Embodiment 3 FIG. 4 is a block diagram showing a facsimile apparatus according to Embodiment 3 of the present invention. In the figure, reference numeral 31 denotes a local area network interface (hereinafter, LAN I / O) connected to a local area network (hereinafter, referred to as LAN). F), 32 is a decoding circuit for decoding and expanding image data received from the LAN I / F 31 via the LAN or image data stored and encoded in the image memory 4 and 33 is a decoding circuit. A resolution conversion circuit that converts the image data decoded by the circuit 32 in accordance with a communication partner device via the LAN at the time of transmission, or simply passes the image data. The compressed image data is encoded and compressed and output to the LAN I / F 31 or the resolution is The image data which has passed through the circuit 33 compresses while coding is a coding circuit to be stored in the image memory 4.
Note that the encoding circuit 34 is configured as an encoding circuit including a lossy encoding circuit 21, a selector 22, and a lossless encoding circuit 23, as shown in FIG. Other configurations are the same as those in FIG.

FIGS. 5 and 6 are system configuration diagrams showing a case where the facsimile apparatus according to the third embodiment of the present invention is applied to a local area network. FIG. Numeral 6 indicates the time of reception from the communication partner. 4, reference numeral 41 denotes a facsimile apparatus having the configuration shown in FIG. 4, reference numeral 42 denotes a communication partner machine, reference numeral 43 denotes a telephone line, reference numeral 44 denotes a LAN, and reference numerals 45a to 45c denote client-side personal computers (hereinafter referred to as personal computers).

Next, the operation will be described. As shown in FIG. 5, when a document created by a word processor or a spreadsheet is transmitted by fax using a telephone directory without printing out the document by a personal computer 45c on the client side, as shown in FIG. Is transmitted to the facsimile apparatus 41 via the LAN 44 or the document is temporarily stored in the file server via the LAN 44 as shown in B, and then the document is transmitted to the facsimile apparatus 4 via the LAN 44.
Send to 1.

As shown in FIG. 4, the facsimile device 41
Then, the image data corresponding to the document is received from the LAN I / F 31, decoded and expanded by the decoding circuit 32, and simply passed through the resolution conversion circuit 33 and output to the encoding circuit 34. The encoding circuit 34 checks the current free space of the image memory 4, and if the free space is equal to or more than a predetermined value, selects the selector 22 to perform lossless compression. When the value is smaller than the predetermined value, the selector 22 is selected so as to perform lossy compression, and the amount of raw image data is reduced and then recorded in the image memory 4. Further, the NCU circuit 8 controls the telephone line 4
3 are connected, the decoding circuit 10 controls the image memory 4
Is decoded and decompressed, and the resolution conversion circuit 11 converts the resolution of the image data according to the communication partner device. Further, the encoding circuit 12 encodes and compresses the image data, and outputs the encoded data to the modem 9.
The modem 9 modulates the image data and modulates the NCU circuit 8.
As shown in FIG. 5C, the data is transmitted to the communication partner device 42 via the telephone line 43.

Further, as shown in FIG.
The document received from the client PC 45c
6, the image data corresponding to the sentence is received by the facsimile device 41 from the communication partner device 42 via the telephone line 43, as shown in FIG. 6D, and as shown in FIG. At 41, the signal received by the NCU circuit 8 is demodulated by the modem 9 and
0 for decoding and decompression, and the resolution conversion circuit 11
Is simply passed through and output to the encoding circuit 12. The encoding circuit 12 checks the current free space of the image memory 4,
If the free space is equal to or larger than a predetermined value, the selector 22 is selected so as to perform lossless compression.
When the free space is less than a predetermined value, the selector 22 is selected so as to perform lossy compression, and the amount of raw image data is reduced before being stored in the image memory 4. Further, the decoding circuit 32 decodes and expands the image data stored in the image memory 4, and the resolution conversion circuit 33 converts the image data according to the client-side personal computers 45 a to 45 c connected to the LAN 44. Do.
The encoding circuit 34 encodes and compresses the image data, outputs the image data to the LAN I / F 31, and directly outputs the document via the LAN 44 to the personal computer 45c as shown in FIG.
Or the document is temporarily stored in the file server 46 via the LAN 44 as shown in F, and then the document is transmitted to the personal computer 45c via the LAN 44.

As described above, according to the third embodiment, the LAN 45 is transmitted from the personal computer 45c via the LAN 44.
When the image data received from the / F31 is recorded in the image memory 4, when the free space of the image memory 4 is smaller than a predetermined value, the selector 22 is switched to compress the image data in a lossy manner, and then the image memory 4 To be stored in the LAN via the LAN 44 from the personal computer 45c.
When the image data received from the I / F 31 is stored in the image memory 4, the occurrence frequency of the memory full of the image memory 4 can be reduced. In the third embodiment, the LAN I / F 31 is transmitted from the personal computer 45c via the LAN 44.
Only the received image data is subjected to the lossy compression. However, when transmitting the image data to the personal computer 45c, the image data may be transmitted after the lossy compression, and in this case, the file server 46 of the LAN 44 may be used. Memory full frequency can be reduced, and the LAN 44
Can be reduced.

Embodiment 4 FIG. FIG. 7 is a block diagram showing a facsimile apparatus according to a fourth embodiment of the present invention. In FIG. 7, reference numeral 51 denotes a facsimile apparatus provided between the encoding circuit 3 and the decoding circuit 5, and the free space of the image memory 4 is predetermined. This selector selects the connection between the decoding circuit 5 and the encoding circuit 3 when the value becomes smaller than the value. Other configurations are the same as those in FIG.

Next, the operation will be described. In the fourth embodiment, when there are a large number of transmission reservations such as timer transmissions and the free space of the image memory 4 does not readily exceed a predetermined value, image data newly stored in the image memory 4 is always replaced with a lossy type. As means for avoiding compression or memory full condition, as shown in the first embodiment, instead of performing lossy compression only on image data to be stored in the image memory 4 from now on,
Lossy compression is also performed on image data already stored in the image memory 4.

In FIG. 7, when the free space of the image memory 4 becomes smaller than a predetermined value, the selector 51 selects the connection between the decoding circuit 5 and the encoding circuit 3. Then, the decoding circuit 5 extracts and decodes and expands the image data stored in the image memory 4 and further highly compresses the image data using a lossy compression method. The image data highly compressed by the lossy encoding circuit 21 is compressed using a lossless compression method,
It is stored in the image memory 4 again.

As described above, according to the fourth embodiment, when the free space of the image memory 4 becomes smaller than the predetermined value, the decoding circuit 5 and the encoding circuit 3 are connected by the selector 51, Since the image data stored in the image memory 4 is extracted, highly compressed using a lossy compression method, and then stored again in the image memory 4, it is possible to increase the current free space of the image memory 4. Yes, image memory 4
Can be reduced.

Embodiment 5 FIG. Embodiment 5 of the present invention
In the first to fourth embodiments, whether or not lossy compression is performed is selected by the operation panel 15, and the lossy encoding circuit 21 responds to the selection of the operation panel 15 by the operation panel 15. Image data.

Next, the operation will be described. In the fourth embodiment, the image data already stored in the image memory 4 is randomly changed from the lossless compression method to the lossy compression method. However, some image data is generated by the lossy compression method. In some cases, even fine distortion cannot be tolerated. Therefore, in this case, the reading unit 1
When reading an original, the operator specifies with the operation panel 15 not to perform the lossy type compression, and the lossy type encoding circuit 21 converts the image data in the lossy type in accordance with the selection of the operation panel 15. Process not to perform compression.

As described above, according to the fifth embodiment, it is possible to select whether or not to perform lossy compression in accordance with the selection of the operation panel 15, so that the lossy compression occurs. This is effective for image data in which even minute distortion cannot be tolerated.

Embodiment 6 FIG. Embodiment 6 of the present invention
In the first to fourth embodiments, lossy image data is forcibly transferred to the lossy encoding circuit 21 by the lossy encoding circuit 21 when a failure occurs in the recording unit 7 or when the recording paper runs out. High compression is performed using a compression method.

Next, the operation will be described. When a failure occurs in the recording unit 7 or when the recording paper runs out, the received image data cannot be processed, and the free space of the image memory 4 may be squeezed. The image data is stored in the image memory 4 by the lossy compression method when the failure of the recording paper or the running out of the recording paper is detected.

As described above, according to the sixth embodiment, when a failure occurs in the recording unit 7 or when the recording paper runs out, the image data is forcibly used by the lossy compression method. Since the compression is performed at high pressure, it is possible to reduce the pressure on the free space of the image memory 4 due to the failure of the recording unit 7 or the running out of the recording paper.

[0047]

As described above, according to the first aspect of the present invention, when the free space of the image memory becomes less than the predetermined value, the image data to be stored is highly compressed by using the lossy compression method. Since a lossy encoding circuit for compressing and storing the image data in the image memory is provided, a facsimile apparatus which reduces the frequency of occurrence of memory full in the image memory is obtained.

According to the second aspect of the present invention, when the free space of the image memory becomes less than a predetermined value, the lossy type compresses the image data read by the reading unit using the lossy compression method. Encoding circuit, when the free space of the image memory is equal to or more than a predetermined value, the image data read by the reading unit,
A lossless encoding circuit that compresses image data highly compressed by a lossy encoding circuit using a lossless compression method when the free space of the image memory becomes less than a predetermined value, and stores the compressed data in the image memory. The facsimile apparatus can reduce the frequency of occurrence of memory full of the image memory when the image data read by the reading unit is recorded in the image memory.

According to the third aspect of the present invention, when the free space of the image memory becomes less than the predetermined value, the image data received from the network control circuit via the communication line is used by the lossy compression method. When the free space of the lossy type encoding circuit which performs high compression and the image memory is a predetermined value or more,
The image data received from the network control circuit via the communication line, and the image data highly compressed by the lossy type encoding circuit when the free space of the image memory becomes less than a predetermined value, is converted into a lossless type. And a lossless coding circuit for compressing the image data using the compression method and storing the image data in the image memory. Therefore, the image data received from the network control circuit via the telephone line by the communication partner is transmitted to the image memory. This has the effect of providing a facsimile apparatus that reduces the frequency of occurrence of memory full of the image memory during recording.

According to the fourth aspect of the present invention, when the free space of the image memory becomes less than a predetermined value, the image data received from the local area network interface via the local area network is converted into a lossy compression system. A lossy encoding circuit that performs high compression using
When the free space of the image memory is equal to or more than a predetermined value, the image data received from the local area network interface via the local area network is used. And a lossless type encoding circuit for compressing image data highly compressed by the type encoding circuit using a lossless type compression method and storing the image data in an image memory. There is an effect that a facsimile apparatus which reduces the frequency of occurrence of memory full of the image memory when the image data received from the area network interface is recorded in the image memory is obtained.

According to the fifth aspect of the present invention, when the free space of the image memory becomes less than a predetermined value, a decoding circuit for extracting and decoding the image data stored in the image memory, and the decoding circuit Encoding circuit that highly compresses the image data extracted by the encoding circuit using a lossy compression method, and compresses the image data highly compressed by the lossy encoding circuit using a lossless compression method In addition, since the image memory is configured to include a lossless encoding circuit for storing the image memory, the free space of the current image memory can be increased, and a facsimile apparatus that reduces the frequency of occurrence of memory full of the image memory can be obtained. effective.

According to the sixth aspect of the present invention, there is provided an operation panel for selecting whether or not to perform lossy type compression, and a lossy type encoding circuit for processing image data in accordance with the selection of the operation panel. With this configuration, even in the case of image data in which even fine distortion generated by the lossy compression method cannot be tolerated, there is an effect that a facsimile apparatus that can guarantee the quality of the image data is obtained.

According to the seventh aspect of the invention, when a failure occurs in the recording unit or when the recording paper runs out, the lossy image data is forcibly compressed by using the lossy compression method. Since the configuration is such that the type encoding circuit is provided, there is an effect that a facsimile apparatus which can reduce the pressure on the free space of the image memory due to the failure of the recording unit or running out of recording paper is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a conventional facsimile apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing an encoding circuit according to Embodiment 1 of the present invention;

FIG. 3 is a flowchart showing an operation of the encoding circuit which is a feature of the first embodiment of the present invention;

FIG. 4 is a block diagram showing a facsimile apparatus according to Embodiment 3 of the present invention.

FIG. 5 is a system configuration diagram showing a case where a facsimile apparatus according to Embodiment 3 of the present invention is applied to a local area network.

FIG. 6 is a system configuration diagram showing a case where a facsimile apparatus according to Embodiment 3 of the present invention is applied to a local area network.

FIG. 7 is a block diagram showing a facsimile apparatus according to Embodiment 4 of the present invention.

[Explanation of symbols]

1 reading unit, 4 image memories, 5, 10, 3
2 decoding circuit, 8 NCU circuit (network control circuit), 15
Operation panel, 21 lossy coding circuit, 23 lossless coding circuit, 31 LAN I / F (local area network interface), 41 facsimile machine, 44 LAN (local area network).

Claims (7)

[Claims] An image memory for storing image data, and, when the free space of the image memory becomes less than a predetermined value,
A facsimile apparatus comprising: a lossy-type encoding circuit that highly compresses image data to be stored using a lossy-type compression method and stores the image data in an image memory. 2. A reading unit for reading written contents of a document and converting the read data into image data, an image memory for storing image data, and the reading unit when the free space of the image memory becomes less than a predetermined value. A lossy-type encoding circuit that highly compresses the read image data using a lossy-type compression method, and losslessly converts the image data read by the reading unit when the free space of the image memory is equal to or more than a predetermined value. When the free space of the image memory becomes smaller than a predetermined value, the image data highly compressed by the lossy encoding circuit is converted to a lossless type. A facsimile apparatus comprising: a lossless encoding circuit that compresses data using a compression method and stores the data in an image memory. 3. A network control circuit connected to a communication line, a decoding circuit for decoding image data received from the network control circuit via the communication line, an image memory for storing image data, A lossy encoding circuit that highly compresses the image data decoded by the decoding circuit using a lossy compression method when the free space of the image memory becomes less than a predetermined value; and When the free space is equal to or more than a predetermined value, the image data decoded by the decoding circuit is compressed using a lossless compression method and stored in the image memory. If the number is less than 1, the image data highly compressed by the lossy encoding circuit is compressed using a lossless compression method, and the lossless code is stored in the image memory. Facsimile machine comprising a conversion circuit. 4. A local area network interface connected to a local area network, a decoding circuit for decoding image data received from the local area network interface via the local area network, and storing the image data. An image memory, and a lossy encoding circuit that highly compresses the image data decoded by the decoding circuit using a lossy compression method when the free space of the image memory becomes less than a predetermined value; When the free space of the image memory is equal to or larger than a predetermined value, the image data decoded by the decoding circuit is compressed using a lossless compression method, stored in the image memory, and stored in the image memory. When the capacity falls below a predetermined value, the high- A facsimile apparatus comprising: a lossless encoding circuit that compresses compressed image data using a lossless compression method and stores the compressed image data in an image memory. 5. An image memory for storing image data, and when the free space of the image memory becomes less than a predetermined value,
A decoding circuit that extracts and decodes the image data stored in the image memory, a lossy encoding circuit that highly compresses the image data extracted by the decoding circuit using a lossy compression method, A facsimile apparatus comprising: a lossless encoding circuit that compresses image data highly compressed by the lossy encoding circuit using a lossless compression method and stores the data in the image memory. 6. An operation panel for selecting whether or not to perform lossy compression, and a lossy encoding circuit for processing image data in accordance with the selection of the operation panel. Any one of items 1 to 5
The facsimile apparatus according to the item. 7. A recording unit for recording image data stored in an image memory on recording paper, and forcibly transmitting the image data when a failure occurs in the recording unit or when the recording paper runs out. The facsimile apparatus according to any one of claims 1 to 5, further comprising a lossy type encoding circuit that performs high compression using a lossy type compression method.