Data communication system and facsimile machine in the data communication system

A data transmission apparatus operatively connected to another data transmission apparatus for transmitting data in a state where an amount of data to be transmitted for each block is not less than a minimum value of a total amount of data to be transmitted for each block, and the data to be transmitted for each block includes data from which fill bits are eliminated, said data transmission apparatus comprising:

• storage means for storing said data from which fill bits have been eliminated out of the data received for each block by said transmission apparatus;
• processing means for processing the data from which fill bits are eliminated, read out from said storage means;
• determination means for determining, based on an amount of data from which fill bits are eliminated, which has not yet been processed and remains in said storage means, whether or not the minimum value of the total amount of data to be transmitted for each block can be changed;
• and
• signal output means for outputting, when said determination means determines that the minimum value of the total amount of data to be transmitted for each block can be changed, a request signal, the request signal being transmitted to another data transmission apparatus operatively connected to said data transmission apparatus.

A facsimile machine comprising:

• a transmitter unit for transmitting data in a state where an amount of data to be transmitted for each scanning line is not less than a minimum value of a total amount of data to be transmitted for each scanning line, and the data for each scanning line includes image data as data from which fill bits are eliminated;
• and
• a receiving unit for receiving data transmitted from another facsimile machine operatively connected to said facsimile machine,
• said receiving unit including:
• storage means for storing the image data out of the data received for each scanning line by said receiving unit;
• processing means for processing the image data read out from said storage means;
• printing means for performing a printing operation of the image data read out from said storage means and processed by said processing means;
• determination means for determining, based on an amount of image data which has not yet been processed in said processing means and remains in said storage means, whether or not the minimum value of the total amount of data to be transmitted for each scanning line can be changed;
• and
• signal output means for outputting, when said determination means determines that the minimum value of the total amount of data to be transmitted for each scanning line can be changed, a request signal, the request signal being transmitted to another facsimile machine operatively coupled to said facsimile machine.

A facsimile machine comprising:

• a transmission unit for transmitting data in a state where an amount of data to be transmitted for each scanning line is not less than a minimum value of a total amount of data to be transmitted for each scanning line, and the data for each scanning line includes image data as data from which fill bits are eliminated;
• and
• a receiving unit for receiving data transmitted from another facsimile machine operatively connected to said facsimile machine,
• said transmission unit including:
• detecting means for detecting a request signal from another facsimile machine, the request signal indicating that the minimum value of the amount of data to be transmitted for each scanning line is changed;
• and
• changing means for changing, when said detecting means detects the request signal, the minimum value of the total amount of data to be transmitted for each scanning line, so that the data is transmitted in a state where a changed minimum value of the total amount of data to be transmitted for each scanning line is ensured.

A data communication system comprising:

• a transmitter for transmitting data in a state where an amount of data to be transmitted for each block is not less than a minimum value of a total amount of data to be transmitted for each block, the data to be transmitted for each block including data from which fill bits are eliminated;
• and
• a receiver, operatively connected to said transmitter, for receiving the data transmitted from said transmitter,
• said receiver comprising:
• storage means for storing the data from which fill bits are eliminated out of the data received for each block by said receiver;
• processing means for processing the data from which fill bits are eliminated, read out from said storage means;
• determination means for determining, based on an amount of data from which fill bits are eliminated and which has not yet been processed and remains in said storage means, whether or not the minimum value of the total amount of data to be transmitted for each block can be changed;
• and
• signal output means for outputting, when said determination means determines that the minimum value of the total amount of data to be transmitted for each block can be changed, a request signal, the request signal being transmitted to said transmitter,
• said transmitter comprising:
• detecting means for detecting the request signal from said receiver;
• and
• changing means for changing, when said detecting means detects the request signal, the minimum value of the total amount of data to be transmitted for each block, so that the data is transmitted in a state where a changed minimum value of the total amount of data to be transmitted for each block is ensured;
• wherein said determination means of said receiver has at least first means for determining whether or not the minimum value of the total amount of data to be transmitted for each block can be decreased, said signal output means outputting a first request signal when said first means determines that the minimum value of the total amount of data to be transmitted for each block can be decreased, and wherein said changing means of said transmitter has decreasing means for decreasing the minimum value of the total amount of data to be transmitted for each block when said detecting means detects the first request signal from said receiver;
• wherein said decreasing means has means for setting the minimum value of the total amount of data to be transmitted for each block at zero so that only the data from which fill bits are eliminated is transmitted for each block by said transmitter.