Color Sequence Pattern Decoding Under Defocus and Low Contrast
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pattern generation and decoding methods are limited by environmental constraints, such as requiring controlled lighting conditions and being susceptible to defects like defocus and low contrast ratios, making them unsuitable for non-expert users in everyday environments.
Innovation Solution
A pattern generation method that arranges elements with colors from a color candidate group with equal differences, ensuring distinct color sequences in sub-arrays and maintaining minimum distance thresholds, and a decoding method that uses pixel intensity peaks to identify the original color sequence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If phase shifting or gray code methods are used to expand information in patterns, then the amount of information in the pattern increases, but the number of shots required increases and the methods become vulnerable to ambient light and surrounding environment
Solution Approach 1:
The patent transitions from temporal domain information encoding (requiring multiple shots) to spatial domain encoding using color sequences. By arranging elements with distinct color sequences in different spatial locations, the pattern can encode more information in a single captured image, eliminating the need for multiple shots and reducing vulnerability to environmental factors.
Solution Approach 2:
The patent uses color as an additional parameter for encoding information. By selecting colors from a color candidate group with equal differences and ensuring distinct color sequences for different sub-arrays, the system increases the information capacity of each pattern element without requiring multiple temporal shots, thereby improving reliability in ambient light conditions.
2Measurement precision
If black and white colors are used in fiducial markers for easy detection, then the contrast ratio is high and detection is easy, but the amount of information that can be included is limited
Solution Approach 1:
The patent extends the color space from binary black and white to a color candidate group with multiple distinct colors. By selecting colors with equal differences from this group and ensuring distinct color sequences for different sub-arrays, the system maintains high detectability while significantly increasing the information capacity of the fiducial marker.
Solution Approach 2:
The patent adds the color dimension to the traditional black and white fiducial marker system. By using distinct color sequences in spatial arrangements, the system encodes additional information beyond what is possible with binary contrast alone, allowing more data to be contained within the same physical marker size.
3Loss of information
If the number of pixels in fiducial marker is increased to include more information, then the information capacity increases, but the size of the fiducial marker increases and resolution decreases
Solution Approach 1:
The patent uses color sequences as an additional encoding parameter, allowing information to be stored in the color dimension rather than solely in the spatial pixel dimension. This enables increased information capacity without proportionally increasing the physical size or reducing the resolution of the fiducial marker.
Solution Approach 2:
The patent creates a composite encoding scheme combining spatial arrangement of elements with color sequencing. This multi-dimensional encoding approach allows the fiducial marker to contain more information within the same physical footprint, effectively increasing information density without compromising resolution.
4Ease of operation
If border detection is used for pattern decoding, then the decoding process is simple, but the detection rate is low when boundary lines are damaged due to defocus or hand shaking
Solution Approach 1:
The patent moves the decoding focus from spatial border detection to color sequence analysis. By encoding information in color sequences that can be detected through pixel intensity peaks rather than relying on precise boundary line detection, the system maintains decoding simplicity while significantly improving robustness against defocus and hand-shaking artifacts.
Solution Approach 2:
The patent changes the detection parameter from border position to pixel intensity peak. By identifying colors based on intensity peaks within elements rather than detecting boundary lines between elements, the system achieves both simplicity and reliability in decoding even when boundaries are damaged or blurred.
Data Source
AI summary
A method includes generating a pattern, and projecting the pattern. A plurality of elements are arranged in the pattern. The method further includes selecting a color for each of the plurality of elements from a color candidate group including a plurality of colors with equal differences between the plurality of colors. The color of each of the plurality of elements is different from a neighboring color of a neighboring element adjacent to that element. A plurality of color sequences corresponding to a plurality of sub-arrays are different from each other. The plurality of sub-arrays includes at least one element from among the plurality of elements. Distances between pairs of color sequences of the plurality of color sequences within the pattern are greater than or equal to a predetermined threshold.