Image encoding apparatus and control method thereof

An image encoding apparatus for dividing an image into rectangle regions and encoding image data in each rectangle region, comprising:

• a region detector that detects a specific region in image data;
• a tile divider that determines positions of a vertical line and a horizontal line as boundaries to divide said image into a plurality of tiles having the same height in the same row and the same width in the same column, in accordance with coordinates of each rectangle region including each specific region detected by said region detector;
• and
• an encoder that divides said image data in accordance with the horizontal and vertical lines set by said tile dividing unit and encodes a partial image in each divided region as said tile,
• wherein, when a minimum encoding processing unit of said encoder is defined as a pixel block,
• said tile divider, comprising:
• a determination unit that determines whether or not each pixel block in said image is included in any specific region detected by said region detector, and determines the result of determination as binary flag information of each pixel block;
• a first operation unit that obtains a logical OR of said flag information of pixel blocks arrayed in a vertical direction;
• a second operation unit that obtains a logical OR of said flag information of pixel blocks arrayed in a horizontal direction;
• and
• a determination unit that determines positions of horizontal line and vertical line to tile-divide said image in accordance with the result of operation by said first operation unit and the result of operation by second operation unit.

An image encoding apparatus for dividing an image into rectangle regions and encoding image data in each rectangle region, comprising:

• a region detector that detects a specific region in image data;
• a tile divider that determines positions of a vertical line and a horizontal line as boundaries to divide said image into a plurality of tiles having the same height in the same row and the same width in the same column, in accordance with coordinates of each rectangle region including each specific region detected by said region detector;
• an encoder that divides said image data in accordance with the horizontal and vertical lines set by said tile divider and encodes a partial image in each divided region as said tile,
• a setting unit that sets a number N of specific regions with priorities;
• and
• a re-setting unit that, when a rectangle region of interest represented with lines not to be deleted includes the specific regions more than the number N set by said setting unit, re-sets horizontal and vertical lines determined as lines to be deleted with respect to higher N specific regions arrayed in accordance with a predetermined condition in said rectangle region of interest, as lines not to be deleted,
• wherein said encoder divides said image data in accordance with the result of processing by said re-setting unit and encodes each divided region as said tile.

A control method for an image encoding apparatus for dividing an image into two or more rectangle regions and encoding image data in each rectangle region, comprising:

• a region detection step of detecting one or more specific region in image data;
• a tile dividing step of determining positions of a vertical line and a horizontal line as boundaries to divide said image into a plurality of tiles whose size are variable and which have the same height in the same row and the same width in the same column, in accordance with coordinates of each rectangle region including each specific region detected at said region detection step;
• and
• an encoding step of dividing said image data in accordance with the horizontal and vertical lines set at said tile dividing step and encoding a partial image in each divided region as said tile,
• wherein, if the detecting step detects specific regions more than a predetermined number, said tile dividing step divides said image into the plurality of tiles in accordance with coordinates of rectangle regions of only N specific regions among the detected specific regions, where N is determined in accordance with a predetermined condition.

A control method for an image encoding apparatus for dividing an image into rectangle regions and encoding image data in each rectangle region, comprising:

• a region detection step of detecting a specific region in image data;
• a tile dividing step of determining positions of a vertical line and a horizontal line as boundaries to divide said image into a plurality of tiles having the same height in the same row and the same width in the same column, in accordance with coordinates of each rectangle region including each specific region detected at said region detection step;
• and
• an encoding step of dividing said image data in accordance with the horizontal and vertical lines set at said tile dividing step and encoding a partial image in each divided region as said tile,
• wherein, when a minimum encoding processing step of said encoding step is defined as a pixel block,
• said tile dividing step, comprising:
• a determination step of determining whether or not each pixel block in said image is included in any specific region detected by said region detection step, and determines the result of determination as binary flag information of each pixel block;
• a first operation step of obtaining a logical OR of said flag information of pixel blocks arrayed in a vertical direction;
• a second operation step of obtaining a logical OR of said flag information of pixel blocks arrayed in a horizontal direction;
• and
• a determination step of determining positions of horizontal line and vertical line to tile-divide said image in accordance with the result of operation by said first operation step and the result of operation by second operation step.

A control method for an image encoding apparatus for dividing an image into rectangle regions and encoding image data in each rectangle region, comprising:

• a region detection step of detecting a specific region in image data;
• a tile dividing step of determining positions of a vertical line and a horizontal line as boundaries to divide said image into a plurality of tiles having the same height in the same row and the same width in the same column, in accordance with coordinates of each rectangle region including each specific region detected at said region detection step;
• and
• an encoding step of dividing said image data in accordance with the horizontal and vertical lines set at said tile dividing step and encoding a partial image in each divided region as said tile,
• a setting step of setting a number N of specific regions with priorities;
• and
• a re-setting step of, when a rectangle region of interest represented with lines not to be deleted includes the specific regions more than the number N set by said setting step, re-setting horizontal and vertical lines determined as lines to be deleted with respect to higher N specific regions arrayed in accordance with a predetermined condition in said rectangle region of interest, as lines not to be deleted,
• wherein said encoding step divides said image data in accordance with the result of processing by said re-setting step and encodes each divided region as said tile.