Cell-Based Compression with Edge Detection and Interleaved Encoding

An article of manufacture including a non-transitory computer-readable medium, having stored thereon program instructions that, upon execution by a processor of a computing device, cause the computing device to perform operations comprising:

• obtaining, from a memory, (i) an attribute plane containing a plurality of a×b attribute macro-cells, and (ii) a digital image containing pluralities of a×b pixel macro-cells for each of a luminance plane, a first color plane, and a second color plane, wherein the a×b pixel macro-cells each contain 4 non-overlapping m×n pixel cells, wherein elements of the a×b attribute macro-cells are associated with respective pixels in each of the a×b pixel macro-cells;
• applying compression to each particular a×b attribute cell and its associated a×b pixel macro-cells, wherein applying the compression comprises:
• determining 4 attribute-plane output values that respectively represent 4 non-overlapping m×n attribute cells in the particular a×b attribute macro-cell,
• based at least partially on whether the particular a×b attribute macro-cell indicates that at least e pixels in each of the associated a×b pixel macro-cells represent edges in the digital image, determining 1 to 4 luminance-plane output values that represent the associated a×b pixel macro-cell of the luminance plane, wherein e is at least 1, and
• determining a first color-plane output value to represent the associated a×b pixel macro-cell of the first color plane and a second color-plane output value to represent the associated a×b pixel macro-cell of the second color plane;
• and
• storing, in the memory, a compressed representation of the digital image and the attribute plane, wherein 4 attribute-plane output values, the 1 to 4 luminance-plane output values, the first color-plane output value, and the second color-plane output value are interleaved with one another in the compressed representation.

A printing device comprising:

• at least one processor;
• memory;
• and
• program instructions, stored in the memory, that upon execution by the at least one processor cause the printing device to perform operations comprising:
• obtaining, from the memory, (i) an attribute plane containing a plurality of a×b attribute macro-cells, and (ii) a digital image containing pluralities of a×b pixel macro-cells for each of a luminance plane, a first color plane, and a second color plane, wherein the a×b pixel macro-cells each contain 4 non-overlapping m×n pixel cells, wherein elements of the a×b attribute macro-cells are associated with respective pixels in each of the a×b pixel macro-cells;
• applying compression to each particular a×b attribute cell and its associated a×b pixel macro-cells, wherein applying the compression comprises:
• determining 4 attribute-plane output values that respectively represent 4 non-overlapping m×n attribute cells in the particular a×b attribute macro-cell,
• based at least partially on whether the particular a×b attribute macro-cell indicates that at least e pixels in each of the associated a×b pixel macro-cells represent edges in the digital image, determining 1 to 4 luminance-plane output values that represent the associated a×b pixel macro-cell of the luminance plane, wherein e is at least 1, and
• determining a first color-plane output value to represent the associated a×b pixel macro-cell of the first color plane and a second color-plane output value to represent the associated a×b pixel macro-cell of the second color plane;
• and
• storing, in the memory, a compressed representation of the digital image and the attribute plane, wherein 4 attribute-plane output values, the 1 to 4 luminance-plane output values, the first color-plane output value, and the second color-plane output value are interleaved with one another in the compressed representation.