Quadra Image Sensor Defect Detection Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Quadra image sensors with pixel tiles increase processing complexity and time due to higher pixel density, and existing image processing techniques are not suitable for detecting and correcting defects in images captured by these sensors.
Innovation Solution
A defect detection circuit analyzes pixel data to identify defective pixels by comparing pixel values with surrounding tiles and the same tile, and corrects them by interpolating data based on gradient values and linear filter correction, using a pixel defect correction circuit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If pixel density is increased using quadra configuration, then image quality and detail are improved, but processing complexity and time increase
Solution Approach 1:
The image sensor is divided into multiple pixel tiles, where each tile contains pixels of the same color. This segmentation allows independent processing of each tile, reducing the overall processing complexity while maintaining high pixel density and image quality.
Solution Approach 2:
Defect detection is performed before final image processing by comparing pixel values within and between tiles. This preliminary defect identification allows for early correction or flagging of problematic pixels, streamlining the subsequent processing pipeline.
2Measurement precision
If pixel density is increased using quadra configuration, then image quality is improved, but processing time increases
Solution Approach 1:
By segmenting the sensor into independent pixel tiles with uniform color properties, each tile can be processed separately and in parallel, significantly reducing the total processing time while maintaining high image quality through the increased pixel density.
Solution Approach 2:
The defect detection circuit performs comparisons with a limited set of reference pixels (within-tile and between-tile) rather than analyzing all pixels exhaustively. This partial action approach efficiently identifies defects without requiring complete processing of the entire high-density pixel array.
3Device complexity
If existing image processing techniques are used, then processing is simpler, but they are not suitable for detecting and correcting defects in quadra sensor images
Solution Approach 1:
The defect detection algorithm is specifically adapted for quadra sensor architecture by implementing local comparisons within pixel tiles and between adjacent tiles. This localized approach accounts for the specific quadra structure, ensuring reliable defect detection while keeping the processing methodology tailored to this sensor type.
Solution Approach 2:
A dedicated defect detection circuit serves as an intermediary between the pixel array and the main image processing pipeline. This intermediary component specifically handles defect identification and correction for quadra sensors, bridging the gap between the unique sensor architecture and standard processing techniques.
Data Source
AI summary
Embodiments relate to correcting pixels of images captured using a quadra image sensor. A defect detection circuit analyzes the pixels in the captured image and determines whether a pixel is defective. The defect detection circuit generates a first defect indication by determining whether pixel data of a pixel under test is brighter or darker by a first threshold value than pixel data of pixels in pixel tiles surrounding the pixel tile corresponding to the pixel under test. Moreover, the defect detection circuit generates a second defect indication by determining whether pixel data of the pixel under test is brighter or darker by a second threshold value than pixel data of other pixels in the pixel tile corresponding to the pixel under test. Using the first and second defect indications, the defect detection circuit identifies whether the pixel data of the pixel under test is defective.