Image Processing Apparatus

A method for processing a dithered image comprising a grid of pixels, the method comprising:

• defining an array of pixels corresponding to a sub-region of the image;
• detecting segments of similar pixels in the lines of the array, wherein the difference in pixel value between neighbouring pixels in a segment is less than a predetermined contrast threshold;
• identifying whether the sub-region is dithered based on the lengths of the segments;
• and
• selectively processing the corresponding sub-region of the image based on whether or not the sub-region is identified to be dithered.

A non-transitory computer readable medium having a computer program stored thereon to implement a method for processing a dithered image comprising a grid of pixels, the method comprising:

• defining an array of pixels corresponding to a sub-region of the image;
• performing edge detection along the rows and the columns of the array;
• counting the number of edges detected along the rows of the array to determine the number of horizontal edges in the array;
• counting the number of edges detected along the columns of the array to determine the number of vertical edges in the array;
• identifying whether the sub-region is dithered based on the number of horizontal and vertical edges in the array;
• and
• selectively processing the corresponding sub-region of the image based on whether or not the sub-region is identified to be dithered.