Adaptive autocolor detection based on media color

A system for detecting background color of a scanned document, the system comprising:

• a non-transitory storage device having stored thereon instructions for:
• detecting the background color of a scanned document, the detecting comprising:
• (a) for a given pixel (i,j), identifying a block of pixels around the given pixel, each pixel in the block having a respective luminance L* value and chroma a* and b* values;
• (b) applying the L*a*b* values of the given pixel to a series of thresholds, the thresholds being based on weighted intensity values in the block;
• (c) in response to the L*a*b* values of the given pixel meeting the series of thresholds, searching the memory for a stored luminance value L* matching the luminance value L of the given pixel, reassigning the stored luminance value L* a new weight value of zero, treating the reassigned luminance value as being monochromatic, classifying the pixel as being monochromatic and dynamically updating the predetermined weight values in the memory to include the new weight value;
• repeating steps (a)-(c) for remaining pixels in the document;
• and
• generating an output document using the classified pixels, the output document having a monochrome background;
• at least one hardware processor being part of the computing device and configured to execute the instructions;
• and
• a display device in communication with the computing device, the display device for displaying the output document.

A computer-implemented method for detecting background color of a scanned document, the method comprising:

• at a server computer:
• in response to acquiring a scanned document including colored content on a colored background canvas, obtaining predetermined weight values stored in a memory;
• detecting the content pixels from the background pixels, comprising:
• (a) for a given content pixel (i,j), identifying a block of pixels around the given pixel, each pixel in the block having a respective luminance L* and chroma a* and b* value;
• (b) applying the L*a*b* values of the given pixel to a series of thresholds;
• (c) in response to the L*a*b* values of the given content pixel meeting the series of thresholds, classifying the content pixel as being monochromatic and reassigning the stored luminance value L* matching the luminance of the given content pixel a new weight value of zero “0”;
• repeating steps (a)-(c) for remaining pixels in the document;
• generating an output document using the classified pixels, the output document including a monochromatic content on the colored background;
• and
• transmitting the output document to a display device in communication with the server computer.