The parameters of an optical code are optimized to achieve improved signal robustness, reliability, capacity and/or visual quality. An optimization program can determine spatial density, dot distance, dot size and signal component priority to optimize robustness. An optical code generator employs these parameters to produce an optical code at the desired spatial density and robustness. The optical code is merged into a host image, such as imagery, text and graphics of a package or label, or it may be printed by itself, e.g., on an otherwise blank label or carton. A great number of other features and arrangements are also detailed.

Briefly, a method for verifying the visual perceptibility of a display is provided. An intended message is written to a bistable display. Pixels that comprise portions of the message are measured and evaluated to determine if the message actually displayed on the bistable display was perceptible by a human or a machine. In some cases, information regarding the message actually perceivable from the display may be stored for later use. Responsive to determining that a message is perceivable or not perceivable, alarms may be set, one or more third parties notified, or additional display features may be set.

A method, an apparatus, and a terminal for recognizing a two-dimensional code are provided. The two-dimensional code includes an image region and an encoding region. The image region and the encoding region have no overlap. The method includes selecting, from pixels of the two-dimensional code, a pixel included in a code element in an encoding region. The method further includes determining a value of the code element in the encoding region according to the pixel included in the code element in the encoding region. The method further includes recognizing the two-dimensional code according to the value of the code element in the encoding region.

Briefly, a method for verifying the visual perceptibility of a display is provided. An intended message is written to a bistable display. Pixels that comprise portions of the message are measured and evaluated to determine if the message actually displayed on the bistable display was perceptible by a human or a machine. In some cases, information regarding the message actually perceivable from the display may be stored for later use. Responsive to determining that a message is perceivable or not perceivable, alarms may be set, one or more third parties notified, or additional display features may be set.

In some examples, an article includes a substrate and a plurality of optical element sets embodied on the substrate, wherein each optical element set includes a plurality of optical elements, wherein each respective optical element represents an encoded value in a set of encoded values, wherein the set of encoded values are differentiable based on visual differentiability of the respective optical elements, wherein each respective optical element set represents at least a portion of a message or error correction data to decode the message if one or more of the plurality of optical element sets are visually occluded, and wherein the optical element sets for the message and error correction data are spatially configured at the physical surface in a matrix such that the message is decodable from the substrate without optical elements positioned within at least one complete edge of the matrix that is visually occluded.

Systems and methods illustrated herein disclose error correction of a two-dimensional (2D) symbol. The systems and methods include reading, by a hardware processor, a plurality of codewords in the 2D symbol. Further, the systems and methods include identifying, by the hardware processor of, an optically ambiguous codeword of the plurality of codewords in the 2D symbol. The optically ambiguous codeword corresponds to a codeword with a minimum interior contrast level below a predefined minimum interior contrast level. Further, the systems and methods include correcting, by the hardware processor, errors in the optically ambiguous codeword based on, a location of the optically ambiguous codeword and an erroneous decoded value associated with the optically ambiguous codeword.

A two-dimensional code generation method and apparatus, a two-dimensional code identification method and apparatus, an electronic device, and a storage medium are provided. The method includes generating a data codeword sequence according to input information, encrypting the data codeword sequence to generate an encrypted codeword sequence, determining a number of error correction blocks, and generating the two-dimensional code from the data codeword sequence and the encrypted codeword sequence according to a construction mode corresponding to the number of error correction blocks.

Aspects of this disclosure include technologies for detecting mislabeled products. In one embodiment, the disclosed system will capture an image of a product when the MRL of the product is scanned or being scanned. After recognizing the product in the image, the size of the area containing the product may be calculated. Subsequently, the disclosed system can determine whether the MRL mismatches the product in the image if this size of the area containing the product does not match the standard size associated with the MRL.

Systems and methods are provided for detecting anomalies, for instance, user-caused scanning anomalies, which occur during scanning transactions. Scanning-related events may be detected by a scanning device and notifications of such events may be transmitted from the scanning device to a point-of-sale (POS) host device coupled therewith. In aspects, the notifications transmitted to the POS host device include a unique code (e.g., a barcode or label) that is indicative of the corresponding event. Responsive to receipt of the event notifications and the nature thereof, the POS host device may initiate one or more anomaly detection actions.

Embodiments of this application disclose an object on which a two-dimensional code is disposed, a two-dimensional code generation method, identification method, generation apparatus, and identification apparatus, and a storage medium. The two-dimensional code includes a square module array of m*m modules. The square module array includes a location detection pattern and a data information pattern. The location detection pattern is used for determining a location of the two-dimensional code. The data information pattern is used for carrying data. m=17 or 18 or 19 or 20. Even if printed in a miniature area whose side length is 0.5 cm to 0.7 cm, a miniature two-dimensional code provided in the embodiments of this application can still be normally identified, and is suitable for being used in a small area application scenario such as an inner side of a bottle cap or a corner of an object.