Image processing apparatus and method, and program

An image processing method for an image processing apparatus configured to extract an edge point which is a pixel constituting an edge in an image, perform an analysis as to whether or not a blur is generated in the extracted edge point, and detect a blur state of the image on the basis of the analysis result, the image processing method comprising the steps of:

• detecting an intensity of the edge of the image in units of a block of a predetermined size;
• setting initial values of an edge reference value used for a determination as to whether or not this is the edge point and an extraction reference value used for a determination as to whether or not an extraction amount of the edge point is appropriate as larger values as a dynamic range which is a difference between a maximum value and a minimum value of the edge intensity of the image is larger;
• extracting as the edge point a pixel in an edge block which is a block where the detected edge intensity is equal to or larger than the edge reference value;
• determining whether or not the extraction amount of the edge point is appropriate through a comparison with the extraction reference value;
• and
• repeating, until it is determined that the extraction amount of the edge point is appropriate,
• a processing of adjusting the edge reference value in a direction in which the extraction amount of the edge point becomes appropriate, and
• a processing of extracting the edge point used for the detection of the blur state of the image on the basis of the adjusted edge reference value.

A program instructing a computer to execute a processing of extracting an edge point which is a pixel constituting an edge in an image, performing an analysis as to whether or not a blur is generated in the extracted edge point, and detecting a blur state of the image on the basis of the analysis result, the program instructing the computer to execute a processing comprising the steps of:

• detecting an intensity of the edge of the image in units of a block of a predetermined size;
• setting initial values of an edge reference value used for a determination as to whether or not this is the edge point and an extraction reference value used for a determination as to whether or not an extraction amount of the edge point is appropriate as larger values as a dynamic range which is a difference between a maximum value and a minimum value of the edge intensity of the image is larger;
• extracting as the edge point a pixel in an edge block which is a block where the detected edge intensity is equal to or larger than the edge reference value;
• determining whether or not the extraction amount of the edge point is appropriate through a comparison with the extraction reference value;
• and
• repeating, until it is determined that the extraction amount of the edge point is appropriate,
• a processing of adjusting the edge reference value in a direction in which the extraction amount of the edge point becomes appropriate, and
• a processing of extracting the edge point used for the detection of the blur state of the image on the basis of the adjusted edge reference value.

An image processing apparatus configured to extract an edge point which is a pixel constituting an edge in an image, perform an analysis as to whether or not a blur is generated in the extracted edge point, and detect a blur state of the image on the basis of the analysis result, the image processing apparatus comprising:

• an edge intensity detection unit adapted to detect an intensity of the edge of the image in units of a block of a predetermined size;
• a parameter adjustment unit adapted to adjust an edge reference value used for a determination as to whether or not this is the edge point and an extraction reference value used for a determination as to whether or not an extraction amount of the edge point is appropriate, and also set initial values of the edge reference value and the extraction reference value as larger values as a dynamic range which is a difference between a maximum value and a minimum value of the edge intensity of the image is larger;
• an edge point extraction unit adapted to extract as the edge point a pixel in an edge block which is a block where the detected edge intensity is equal to or larger than the edge reference value;
• and
• an extraction amount determination unit adapted to determine whether or not the extraction amount of the edge point is appropriate through a comparison with the extraction reference value,
• wherein the parameter adjustment unit repeatedly performs a processing of adjusting the edge reference value in a direction in which the extraction amount of the edge point becomes appropriate until it is determined that the extraction amount of the edge point is appropriate, and
• wherein the edge point extraction unit repeatedly performs a processing of extracting the edge point used for the detection of the blur state of the image on the basis of the edge reference value adjusted by the parameter adjustment unit until it is determined that the extraction amount of the edge point is appropriate.