Method and apparatus for decoding or generating multi-layer color QR code, method for recommending setting parameters in generation of multi-layer QR code, and product comprising multi-layer color QR code

A method for generating a multi-layer color QR code from data to be encoded, comprising:

• partitioning the data to be encoded into a plurality of data blocks according to the number of layers and an error correction level of each layer specified by a user;
• breaking the data in all the data blocks into bits;
• encoding the portioned data blocks into a plurality of monochrome QR codes independently, wherein each monochrome QR code shares a same dimension;
• shuffling the data blocks in each monochrome QR code in a bit-by-bit manner randomly or based on sizes of each monochrome QR code;
• combining all the monochrome QR codes to generate a multi-layer color QR code using a predefined color codebook;
• and
• adding color constraints to spatial patterns,
• wherein the adding of color constraints to spatial patterns comprises:
• coloring all finder patterns and alignment patterns with a set of color to reduce false positives in a localization process.

An apparatus for decoding a multi-layer color QR code, comprising:

• a processor;
• and
• a memory;
• the memory storing computer-readable instructions which when executed by the processor, cause the processor to:
• capture an image of one or more two-dimensional multi-layer color QR codes having a plurality of layers of encoded data;
• detect rough locations of the color QR codes using a sliding-window based QR code detector trained offline;
• construct, within each detected rough location, a corrected color QR code which is generated by using a robust geometric transformation algorithm;
• perform color recovery over the corrected color QR code by restoring an original color of each color pixel of the corrected color QR code using a color classifier trained offline and further decomposing the restored color QR code to multiple monochrome QR codes using a predefined color codebook used in an encoding process;
• and
• extract the encoded data from the monochrome QR codes layer by layer and concatenating the monochrome QR codes to output the data encoded in the captured color QR code.

An apparatus for generating a multi-layer color QR code from data to be encoded, comprising:

• a processor;
• and
• a memory;
• the memory storing computer-readable instructions which when executed by the processor, cause the processor to perform operations, the operations comprising:
• partitioning the data to be encoded into a plurality of data blocks according to the number of layers and an error correction level of each layer specified by a user;
• breaking the data in all the data blocks into bits;
• encoding the portioned data blocks into a plurality of monochrome QR codes independently, wherein each monochrome QR code shares a same dimension;
• shuffling the data blocks in each monochrome QR code in a bit-by-bit manner randomly or based on sizes of each monochrome QR code;
• combining all the monochrome QR codes to generate a multi-layer color QR code using a predefined color codebook;
• and
• adding color constraints to spatial patterns,
• wherein the adding of color constraints to spatial patterns comprises:
• coloring all finder patterns and alignment patterns with a set of color to reduce false positives in a localization process.