Image processing method and apparatus for rotating an image in an area of an original

An image processing apparatus comprising:

• cut=out means for cutting out a plurality of character images from an original image;
• calculation means for calculating similarities, in a plurality of directions of the character images cut out by said cut-out means;
• first determination means for determining whether or not a difference between the greatest calculated similarity and the second greatest similarity is larger than a predetermined value;
• and
• second determination means for determining a direction of the image as one of the plurality of directions on the basis of the sum of the similarities calculated by said calculation means in a case where said first determination means determines that the difference between the similarities is larger than the predetermined value.

A computer readable memory for storing a program of image processing, comprising the codes of:

• a cut-out step of cutting out a plurality of character images from an original image;
• a calculation step of calculating similarities, in a plurality of directions, of the character images cut out in the cut-out step;
• a first determination step of determining whether or not a difference between the greatest calculated similarity and the second greatest calculated similarity is larger than a predetermined value;
• and
• a second determination step of determining a direction of the original image as one of the plurality of directions on the basis of the sum of the similarities calculated in the calculation step in a case where, in said first determination step, the difference between the similarities is determined to be larger than the predetermined value.

A method of rotating, by 90.degree. degrees, an image block having a predetermined number of lines by a predetermined number of columns, comprising the steps of:

• (a) packing a plurality of adjacent lines in the block into a continuous area;
• (b) masking a content of the area so as to leave pixels of interest included in a column of interest in the block;
• (c) shifting the content of the area by a predetermined shift amount to move a half of the pixels of interest such that a linear positional relationship of the half of the pixels of interest with respect to a remaining half of the pixels is identical after completing the rotation;
• and
• (d) performing an OR operation between the content of the area before shifting and the content of the area resulting from the shifting,
• wherein said steps (c) and (d) are repeated until all pixels of interest are moved to the same relative positions after completing the rotation, and said steps (a) to (d) are repeated until all columns in the block are rotated.

An apparatus for rotating by 90.degree. degrees an image block having a predetermined number of lines by a predetermined number of columns, comprising:

• packing means for packing a plurality of adjacent lines in the block into a continuous area;
• masking means for masking a content of the area so as to leave pixels of interest included in a column of interest in the block;
• and
• shifting means for shifting the content of the area by a predetermined shift amount to move a half of the pixels of interest such that a linear positional relationship of the half of the pixels of interest with respect to a remaining half of the pixels of interest is identical after completing the rotation;
• and
• overlaying means for performing an OR operation between the content of the area before shifting and the content of the area resulting from shifting,
• wherein shifting by said shifting means and the OR operation by said overlaying means are repeated until all of the pixels of interest are moved to the same relative positions after completing the rotation, and wherein packing by said packing means masking by said masking means shifting by said shifting means, and the OR operation by said overlaying means are repeated until all columns in the block are rotated.

A computer program for rotating by 90.degree. degrees an image block having a predetermined number of lines by a predetermined number of columns, stored in a computer-readable medium, having processing steps of:

• (a) packing a plurality of adjacent lines in the block into a continuous area;
• (b) masking a content of the area so as to leave pixels of interest included in a column of interest in the block;
• (c) shifting the content of the area by a predetermined shift amount to move a half of the pixels of interest such that a linear positional relationship of the half of the pixels of interest with respect to a remaining half of the pixels is identical after completing the rotation;
• and
• (d) performing an OR operation between the content of the area before shifting and the content of the area resulting from the shifting,
• wherein said steps (c) and (d) are repeated until all pixels of interest are moved to the same relative positions after completing the rotation, and said steps (a) to (d) are repeated until all columns in the block are rotated.

An apparatus for rotating image data having a predetermined number of bits by a predetermined number of lines, comprising:

• first means for dividing the image data into first and second groups and storing data of the first and second groups, respectively;
• second means for obtaining first masked data where bits of interest in data of the first group are shifted by a predetermined amount and other bits are masked, obtaining second masked data by masking data of the second group except for bits of interest, and obtaining combined data by combining the first and second masked data such that a positional relationship of the bits of interest in the first group with respect to the bits of interest in the second group is identical to a positional relationship of the bits in a line of interest after rotation of the image data;
• and
• third means for shifting the combined data by a predetermined shift amount and combining the shifted data with the combined data such that the bits of interest have a positional relationship in the line of interest after completing the rotation,
• wherein said first, second and third means perform rotation processing until completing rotation of the image data.

A method of rotating image data having a predetermined number of bits by a predetermined number of lines, comprising:

• a first step of dividing the image data into first and second groups and storing data of the first and second groups, respectively;
• a second step of obtaining first masked data where bits of interest in data of the first group are shifted by a predetermined amount and other bits are masked, obtaining second masked data by masking data of the second group except for bits of interest, and obtaining combined data by combining the first and second masked data such that a positional relationship of the bits of interest in the first group with respect to the bits of interest in the second group is identical to a positional relationship of the bits in a line of interest after rotation of the image data;
• and
• a third step of shifting the combined data by a predetermined shift amount and combining the shifted data with the combined data such that the bits of interest have a positional relationship in the line of interest after completing the rotation,
• wherein said first, second and third steps are performed until completing rotation of the image data.

A computer-readable medium storing a computer program to rotate image data having a predetermined number of bits by a predetermined number of lines, said program comprising codes to perform the following steps:

• a first step of dividing the image data into first and second groups and storing data of the first and second groups, respectively;
• a second step of obtaining first masked data where bits of interest in data of the first group are shifted by a predetermined amount and other bits are masked, obtaining second masked data by masking data of the second group except for bits of interest, and obtaining combined data by combining the first and second masked data such that a positional relationship of the bits of interest in the first group with respect to the bits of interest in the second group is identical to a positional relationship of the bits in a line of interest after rotation of the image data;
• and
• a third step of shifting the combined data by a predetermined shift amount and combining the shifted data with the combined data such that the bits of interest have a positional relationship in the line of interest after completing the rotation,
• wherein said first, second and third steps are performed until completing rotation of the image data.