JPH0951411A - Facsimile equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a memory with optimum resolution in the case of memory transmission. SOLUTION: A storage discrimination section 15 monitors the process that data read by a scanner section 4 are compressed and the compressed data are stored in a storage memory 6. If the storage memory 6 is fully occupied on the way of reading an original, the reading is stopped. Image data having already been coded are once decoded and processed with lower resolution again, then the data are coded again. An idle area is reserved in the storage memory and reading of the original is restarted. Thus, it is not required to read again the original read once.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus having a function of storing image data obtained by reading an original in a memory and then transmitting the image data, that is, a memory transmission function, in which the memory is effectively used. Regarding

[0002]

2. Description of the Related Art A facsimile apparatus reads a document image, obtains image data, encodes the image data, and then transmits the image data to a facsimile apparatus of the other party through a communication line. When using a public line, not only the net transmission time of image data but also the reading time of an original document is included in the call charge. Therefore, there is a device having a memory transmission function of temporarily storing the read image data in a memory, then reading the image data from the memory and transmitting the image data. As a result, it is possible to shorten the connection time of the line and to transmit when the line is idle, thus saving the call charge. Also, even in the case of a private network, the exclusive time is shortened and the traffic is reduced.

When using such a memory transmission function, it is necessary to read the entire original document by the apparatus in advance.
However, the memory may become full before all the originals have been read. In such a case,
The reading of the original is interrupted, the resolution of the image data is switched, and the original is read again. Image data with high resolution has a large amount of data, and image data with low resolution has a small amount of data. Therefore, by reducing the image quality, more image data can be stored in the memory.

[0004]

The above-mentioned conventional facsimile apparatus has the following problems to be solved. When the memory transmission is performed, the original is read by the facsimile device in advance. If the memory becomes full during the reading, the user has to read the document again from the beginning, which complicates the work. Moreover, even if the resolution is changed and scanning is performed, there is no guarantee that the memory capacity will be sufficient.
Therefore, the memory may become full again, and the original may be read again.

[0005]

The present invention employs the following structure to solve the above problems. A facsimile apparatus of the present invention includes a scanner unit that reads a document for memory transmission at a preset resolution, a code / decode unit that encodes image data obtained by the scanner unit, and an image after encoding. A storage memory that stores data, a storage determination unit that determines whether the storage memory is full before the encoding of all image data of a document, and the resolution of the document read by the scanner unit are preset and stored. When the storage determination unit determines that the memory is full, it selects the resolution less than the set resolution and changes the setting. The reading resolution selection unit, and when the resolution setting is changed, the storage memory already encoded After the image data stored in is read and decoded by the encoding / decoding unit, resolution conversion processing is performed and encoded again by the encoding / decoding unit. Stored in the storage memory, and a re-encoded Control unit to secure a free space in the storage memory.

Note that the scanner unit may restart reading the original for memory transmission at the changed resolution after the re-encoding control unit secures an empty space in the storage memory.

The accumulation determination unit monitors the process in which the data read by the scanner unit is compressed and accumulated in the accumulation memory.
If the storage memory becomes full during the reading of the document, the reading is stopped. The already encoded image data is once decoded, processed again to a lower resolution, and then recoded. After the empty space is secured in the storage memory in this way, the reading of the document is restarted. Therefore,
There is no need to read the original once read again.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 is a functional block diagram showing an embodiment of a facsimile apparatus of the present invention. The illustrated apparatus shows the internal structure of a facsimile machine controlled by a central processing unit (CPU) 1. This device includes a ROM 3 connected to a CPU 1 via a bus line 2, a scanner unit 4, an image memory 5, a storage memory 6, a DMAC (Direct Memory Access Controller) 7, a modem 8, an encoding / decoding unit 9, and an operation. It is composed of the panel 10 and the like. CPU for ROM (Read Only Memory)
1 stores an operation program for performing processing related to the present invention. Here, the accumulation determination unit 15, the reading resolution selection unit 16, and the re-encoding control unit 17 are described. The specific contents of these will be described in detail later.

The scanner section 4 includes an image line sensor, a binarization circuit, and an image line sensor for reading an original and obtaining image data.
It is composed of a bus interface circuit, a document feeding mechanism, a control unit for controlling these, and the like. Then, for example, the document feeding speed by the document feeding mechanism is changed to select the resolution in the sub-scanning direction. Therefore,
The original can be read at the resolution selected and designated by the reading resolution selecting unit 16 shown in the ROM 3, and an image signal can be obtained for each line. Further, during reading, stop control can be performed for each line in the main scanning direction.

The image memory 5 is a storage device for temporarily storing the binary image data read by the scanner unit 4 before the encoding process. Image data for several lines held for encoding processing is stored here. The storage memory 6 is a storage device for storing encoded image data and enabling memory transmission. DMAC7 is
This is a circuit for transferring the image data read by the scanner unit 4 to the image memory 5 and automatically performing various data transfers. The modem 8 is a device for controlling transmission / reception of image data between the communication line 11 and this facsimile device and executing a predetermined communication protocol.

The encoding / decoding unit 9 reads the image data stored in the image memory 5 and outputs the encoded image data to the storage memory 6, or the encoded data read out from the storage memory 6 for implementing the present invention. It is a circuit that performs a process of decoding the image data that has been converted into the original image data. The operation panel 10 is a part provided with a display or the like for the user to instruct the operation of the facsimile apparatus or to display the status of the apparatus. The operation panel 10 is used to inform the user later whether to execute the memory transmission, or to indicate whether to perform the memory transmission by reducing the resolution when the memory is full. Used for.

The scanner unit 4 is, for example,
Assuming that the resolution in the sub-scanning direction can be changed in three steps of 85 line / mm, 7.7 line / mm, 15.41 line / mm,
The following examples will be described. The accumulation determination unit 15 has a function of notifying the CPU 1 when the accumulated memory 6 becomes full during the reading of an original when the encoded image data is sequentially accumulated in the accumulation memory 6. It is a part. This can be realized by storing the memory capacity of the storage memory 6 and adding a function of accumulating the amount of data each time writing is performed to the storage memory 6 to calculate the remaining memory capacity.

The reading resolution selection unit 16 notifies the scanner unit 4 of the resolution designated in advance by the operation panel 10 to execute the reading of the original document, and when the storage memory is full, the reading resolution selection unit 16 sets the resolution below the preset resolution. When there is a resolution, this is the part that is processed to select and change the setting.

FIG. 2 shows an operation explanatory diagram of the re-encoding processing section. In the present invention, when a document is read, image data is once obtained, and the image data is encoded, even if the storage memory 6 becomes full, control is performed so that the image data read so far is not wasted. For this purpose, the re-encoding control unit 17 performs a certain operation as shown in this figure. That is, when the storage memory 6 becomes full, the encoded image data is read from here, and is decoded by the encoding / decoding unit 9, and then resolution conversion processing is performed. The resolution conversion process is, for example, a process of thinning out image data for each line.

FIG. 3 is a diagram for explaining the conversion processing operation of such a resolution. The resolution conversion by the scanner unit is performed by changing the reading speed. As a result, the pitch of the reading line changes in the sub-scanning direction. If the data once read and encoded is restored and a resolution conversion process equivalent to the output of the scanner unit is to be performed, image data decoded by two lines as shown in FIG. Of these, one line is thinned each time. This allows, for example, the image data read at 7.7 lines / mm to be equal to the image data read at 3.85 lines / mm and encoded again.

If the resolution can be changed by thinning out in the main scanning direction in the scanner unit, the re-encoding control unit 17 performs the resolution conversion process as shown in FIG.
As shown in, the image data may be thinned out by one dot or several dots in the main scanning direction.

Returning to FIG. 2 again, the image data whose resolution has been converted by thinning or the like is encoded again by the encoder / decoder 9 and stored in the storage memory 6. Here, for example, as shown on the right side of the figure, the image data of the already encoded data is D1 and D2, and the portion of the image data that has been sent to the encoding / decoding unit and decoded is D1. Immediately after decoding, the resolution conversion process is performed, the encoding process is performed, and the data is rewritten in the storage memory 6. The image data for this re-encoding is D3.

In this way, the already encoded image data D1
The amount obtained by subtracting the re-encoded data D3 is secured as the empty space M of the storage memory 6. Therefore, by re-encoding all the remaining image data of the already encoded portion D2, a larger empty space is secured. When the document reading is restarted after the empty space is secured by performing such processing, it becomes possible to complete the reading of the document once interrupted and to transmit the document. The above is the operation principle of the re-encoding control unit 17, and the operation including the specific operation of the apparatus of the present invention will be described below with reference to a flowchart.

FIG. 3 shows an operation flowchart of the apparatus of the present invention. First, in the case of starting the memory transmission, in step S1, the transmission original is set in the scanner unit 4 and the original reading is started. In this case, the original is read at the preset resolution. The read image data is transferred to the image memory 5 by the DMAC 7. The image data transferred to the image memory 5 is sequentially transferred to the encoding / decoding unit 9 by the DMAC 7 and encoded (step S2). The encoded image data is transferred to and accumulated in the accumulation memory 6 by the DMAC 7. Here, the accumulation determination unit 15 monitors the amount of image data stored in the accumulation memory 6 in the manner described above and checks the free space of the accumulation memory 6. Then, in step S3, it is determined whether or not the storage memory 6 is full, for example, every time one line of data is written. If the reading of the document is completed before the storage memory 6 becomes full, the process proceeds to step S5 via step S4, and the memory transmission designation completion process is performed. That is, the user is notified through the operation panel 10 that the preparation for the memory transmission is completed, and then the memory transmission is executed.

On the other hand, if it is determined in step S3 that the storage memory 6 is full, the process proceeds to step S6, and it is determined whether or not the current reading resolution is the minimum value. That is, if the reading resolution is the lowest value, the resolution cannot be reduced any more, so it is impossible to perform memory transmission. Therefore, in that case, step S1
Then, the process proceeds to step 2 where the memory transmission cannot be designated. That is, in this case, the user is notified through the operation panel 10 that the memory transmission cannot be performed.

On the other hand, when the reading resolution is not the lowest value, that is, when the reading is performed at the second or higher highest resolution among the three types of resolutions illustrated above,
In step S7, a question is displayed as to whether to reduce the resolution and continue reading the original. This is done through the operation panel 10. Depending on the nature of the manuscript,
It may not be desirable to further reduce the resolution.
In such a case, the user inputs in step S8 that it is impossible to reduce the resolution. In this case, in step S9, it is determined that the process cannot be continued, the process proceeds to step S12, and the process of memory transmission designation is performed. The contents are as described above.

On the other hand, when the user determines that the resolution may be reduced, he / she inputs a key to that effect in step S8. As a result, it is determined that continuation is possible in step S9, and the process proceeds to step S10. In step S10, resolution conversion processing of accumulated image data is performed (step S1).
0). At this time, the reading resolution selection unit 16 changes the setting to 7.7 lines / mm, for example, when reading has been performed at 15.4 lines / mm so far (step S
11). This setting change is notified to the scanner unit 4 and stored for subsequent reading. Further, the notification that the reading resolution is changed is also transmitted to the re-encoding control unit 17. The re-encoding control unit 17 has a reading resolution of ½.
Upon receipt of the notification, the control of the above-described image data decoding and resolution conversion processing is started. That is,
The CPU 1 DMs the image data stored in the storage memory 6.
The AC 7 transfers the data to the encoding / decoding unit 9 for decoding. This image data is transferred to the image memory 5 by the DMAC 7.
Is forwarded to

Here, the re-encoding control unit 17 thins out the image data stored in the image memory 5 from the DMAC 7 in the main operation direction at a rate of one line out of two lines to encode / code.
It instructs the decoding unit 9 to transfer the data. by this,
The encoding / decoding unit 9 re-encodes the image data thinned out line by line. In this way, the image data read at 15.4 line / mm can be converted into the same content as the image data read at 7.7 line / mm and encoded. The image data of the encoding unit is stored in the storage memory 6 again. As a result, an empty space is generated in the storage memory 6. This processing is performed for all encoded image data that has already been read, and after this processing is completed, the scanner unit 4 is notified of the continuation of document reading.

That is, the scanner unit 4 restarts the reading that was interrupted when the storage memory 6 became full.
At this time, the scanner unit 4 changes the reading resolution from one half of the original resolution, that is, 15.4 lines / mm to 7.7 lines / mm, and restarts reading. As a result, the subsequent image data is encoded in the manner described above and stored in the empty memory portion of the storage memory 6. When the storage is completed in this way, the process proceeds to S5 via steps S2, S3 and S4, and memory transmission becomes possible. If the storage memory becomes full even when the reading resolution is changed and reading is performed, in step S3, step S3 is performed again.
It is also possible to move to 6 and lower the resolution by another step.

The present invention is not limited to the above embodiments. In the above-described embodiment, the image memory 5 is used for encoding the image data read from the storage memory 6, performing the resolution conversion process, and then performing the encoding process. However,
For example, as shown in FIG. 2, the read address for the already-encoded portion of the storage memory 6 is displayed by the read pointer 21, while the write pointer 22 for designating the address for re-encoded image data is set. If so, the image memory for the buffer is not required.
That is, one line of already encoded image data pointed by the read pointer 21 is read, the decoding process is performed on the image data, it is determined whether the image data is to be encoded again, and if the encoding is performed, the encoding process is performed. After that, writing is performed at the address designated by the write pointer 22. This procedure may be repeated. In addition to the above-described embodiment, various well-known methods can be adopted as the resolution conversion method.

[0026]

According to the facsimile apparatus of the present invention described above, when the resolution data read by the scanner unit at the preset resolution is encoded and stored in the storage memory, it is determined whether or not the storage memory is full. , When the storage memory is full, select a resolution less than the set resolution and change the setting, read out the image data already encoded and stored in the storage memory, and decode it.
Since the resolution conversion process is performed and the data is encoded again and stored in the storage memory, the image data that has already been read can be used without wasting, and the time for rereading the original can be saved. Further, even if the resolution is changed, the storage memory may become full, but in this case, the reworking work only needs to read the remaining portion of the document, and the operation is simple and easy to use.

[Brief description of drawings]

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

FIG. 2 is an operation explanatory diagram of a re-encoding control unit.

FIG. 3 is an explanatory diagram of a resolution conversion processing operation.

FIG. 4 is an operation flowchart of the device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CPU 4 Scanner section 5 Image memory 6 Storage memory 9 Encoding / decoding section 15 Storage determination section 16 Reading resolution selection section 17 Re-encoding control section

Claims (2)

[Claims] 1. A scanner unit for reading a document for memory transmission at a preset resolution, a coding / decoding unit for coding the image data read by the scanner unit, and the coded image data. An accumulation memory for accumulating, an accumulation determination unit for determining whether or not the accumulation memory is full before encoding of all image data of the original document, a reading resolution of the original document by the scanner unit are preset, and When the storage determination unit determines that the storage memory is full, it selects the resolution below the set resolution and changes the setting, and the reading resolution selection unit, and when the resolution setting is changed, it is already encoded. After the image data stored in the storage memory is read and decoded by the encoding / decoding unit, resolution conversion processing is performed and the encoding / decoding unit encodes again. By, and stored in the storage memory, the facsimile apparatus comprising the re-encoded Control unit to secure a free space in the storage memory. 2. The scanner unit restarts reading of a document for memory transmission at a changed resolution after a free space is secured in the storage memory by the re-encoding control unit. Fax machine.