Ink jet recording apparatus and method

An ink jet recording method for forming on a recording medium an image including a text region that contains at least one of a part of a character and a thin line thinner than a predetermined thickness, and a halftone region that contains a dot image by ejecting ink from recording heads in response to a recording data signal, said method comprising the steps of:

• identifying the text region and the halftone region of said image on the basis of said recording data signal;
• separating recording data associated with a plurality of colors in said halftone region into first recording data and second recording data, said first recording data and said second recording data being complementary to each other;
• recording in a first recording step the first recording data of said halftone region and recording data of said text region;
• and
• recording in a second recording step the second recording data of said halftone region and the recording data of said text region identical to the recording data of said text region recorded in said first recording step.

An ink jet recording apparatus for performing recording on a recording medium by depositing ink onto the recording medium in response to a recording data signal, said apparatus comprising:

• a plurality of recording heads for ejecting inks;
• moving means for causing relative movement of said recording heads and said recording medium;
• recording medium identifying means for identifying a type of said recording medium;
• image identifying means for identifying a recording data signal corresponding to a text region which includes at least one of a part of a character and a line thinner than a predetermined thickness, and for identifying a recording data signal corresponding to a halftone region including a dot image;
• recording data signal processing means for processing said recording data signal based on an identification result by said image identifying means;
• and
• recording controlling means for controlling, when said recording medium identifying means identifies that the recording medium is of low ink absorption, said recording heads so that said recording data signal corresponding to said halftone region is recorded once, while said recording data signal corresponding to said text region is recorded twice, on the same area.

An ink jet recording apparatus for performing recording on a recording medium by depositing ink onto the recording medium in response to a recording data signal, said apparatus comprising:

• a plurality of recording heads for ejecting inks, each of said recording heads electing ink of a predetermined color, at least one of said recording heads ejecting black ink;
• moving means for relatively moving said recording heads and said recording medium;
• image identifying means for identifying a recording data signal corresponding to a text region which includes at least one of a part of a character and a line thinner than a predetermined thickness, and for identifying a recording data signal corresponding to a halftone region including a dot image;
• recording controlling means for controlling recording such that the text region is recorded by said recording head ejecting black ink;
• and
• recording medium identifying means for identifying a type of said recording medium,
• wherein said recording controlling means controls, when said recording medium identifying means identifies that the recording medium is a type of low ink absorption, said recording heads so that the recording data signal corresponding to the halftone region is recorded once, while the recording data signal corresponding to the text region is recorded twice on the same area.

An ink jet recording method for forming on a recording medium an image including a text region that contains at least one of a part of a character and a thin line thinner than a predetermined thickness, and a halftone region that contains a dot image by ejecting ink from recording heads in response to a recording data signal, said method comprising the steps of:

• identifying the text region and the halftone region of said image on the basis of said recording data signal;
• separating recording data associated with a plurality of colors in said halftone region into first recording data and second recording data, said first recording data and said second recording data being complementary to each other;
• and
• controlling recording so that recording of said text region is emphasized relative to recording of said halftone region, wherein said step of identifying the text region and the halftone region comprises the steps of:
• generating a first black signal by suppressing chromatic components of said recording data signal;
• binarizing said first black signal;
• and
• identifying said text regions or said halftone regions on the basis of the binarized first black signal,
• wherein said step of generating a first black signal comprises the steps of:
• detecting a maximum value of R, G and B components of said recording data signal;
• detecting a minimum value of the R, G and B components of said recording data signal;
• subtracting said minimum value from said maximum value;
• multiplying an output of said subtracting step by a predetermined fixed value;
• adding said maximum value and an output of said multiplying step;
• and
• limiting an output of said adding step.

An ink jet recording system, including an ink jet recording section having ink jet recording heads for ejecting inks, for performing recording on a recording medium by ejecting inks from the ink jet recording heads onto the recording medium, the ink jet recording system comprising:

• image identifying means for identifying a text region, including at least one of a character and a line, and a halftone region, of an image to be recorded in accordance with a recording data signal;
• determining means for determining a number of times of performing recording operations for each region of the image to be recorded in accordance with a type of region identified by said image identifying means;
• and
• recording controlling means for controlling said ink jet recording section to perform recording on the recording medium in accordance with the recording data signal and the number of times of performing recording operations for each region determined by said determining means.

An ink jet recording method for performing recording on a recording medium in response to a recording data signal by ejecting ink onto the recording medium from an ink jet recording section having ink jet recording heads for ejecting inks, said ink jet recording method comprising the steps of:

• identifying a text region including at least one of a character and a line, and a halftone region of an image to be recorded in accordance with the recording data signal corresponding to said image;
• determining a number of times of performing recording operations for each region of said image to be recorded, in accordance with a type of region identified in said identification step, and generating a recording number signal corresponding to the determined number of times of recording operations;
• transferring the recording data signal and the recording number signal for each region of said image to the ink jet recording section;
• and
• controlling the ink jet recording section to perform a recording operation on the recording medium, in accordance with the transferred recording data signal and the recording number signal.

An ink jet recording system, including an ink jet recording section having ink jet recording heads for ejecting inks, for performing recording on a recording medium by ejecting inks from the ink jet recording heads onto the recording medium, said ink jet recording system comprising:

• image identifying means for identifying a black portion and a color portion of data of an image to be recorded;
• determining means for determining a recording control operation for the data of the image to be recorded based upon an identification result from said image identifying means;
• and
• a recording controlling section for controlling the ink jet recording section to perform recording in accordance with the data of the image to be recorded and the recording control operation determined by said determining means.

An ink jet recording method for performing recording on a recording medium by ejecting inks from an ink jet recording section having ink jet recording heads for ejecting inks, said method comprising the steps of:

• identifying a black portion and a color portion of data of an image to be recorded;
• determining a recording control operation for the data of the image to be recorded based upon an identification result from said image identifying step, and generating corresponding recording control data;
• transferring the data of the image to be recorded and the recording control data to the ink jet recording section;
• and
• controlling the ink jet recording section to perform recording in accordance with the transferred data of the image to be recorded and the recording control data.