Differentiating half tone areas and edge areas in image processing

A method of processing image data employed in an image processing apparatus, comprising the steps of:

• extracting a luminance component and chrominance components from image data consisting of a plurality of image pixels arrange in a matrix;
• applying a first filter to the extracted luminance component and not the chrominance components to generate first data;
• detecting an edge in the first data;
• applying a second filter to the extracted luminance component and not the chrominance components to generate second data;
• applying a third filter to the extracted luminance component and not the chrominance components to generate third data;
• selectively outputting, in response to the result of edge detection, one of the second data and the third data;
• and
• converting the extracted chrominance components and the one of the second data and the third data selectively output into RGB components.

A tangible computer readable medium having computer readable instructions stored thereon, which when executed by a processor in an image processing apparatus perform a method of processing image data comprising the steps of:

• extracting a luminance component and chrominance components from image data consisting of a plurality of image pixels arrange in a matrix;
• applying a first filter to the extracted luminance component and not the chrominance components to generate first data;
• detecting an edge in the first data;
• applying a second filter to the extracted luminance component and not the chrominance components to generate second data;
• applying a third filter to the extracted luminance component and not the chrominance components to generate third data;
• selectively outputting, in response to the result of edge detection, one of the second data and the third data;
• and
• converting the extracted chrominance components and the one of the second data and the third data selectively output into RGB components.