Parallax Calculation Device Variable Shift Pitch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Stereo camera apparatuses face limitations in measuring short distances due to increased processing time and calculation load, leading to a set measurement limit beyond which parallax calculation becomes impractical.
Innovation Solution
The parallax calculation apparatus adjusts the pitch at which image blocks are shifted during matching, varying it based on the shift amount to optimize processing efficiency and allow measurement up to shorter distances without increasing processing load, while also eliminating the need for previous frame data for short-distance subject detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If blocks of the second image are shifted repeatedly at a uniform pitch (e.g., one pixel at a time) during image matching to accommodate short distance measurement, then measurement precision for short distances is improved, but the amount of calculation and processing time increase significantly
Solution Approach 1:
The patent applies dynamics by making the shift pitch variable rather than fixed. The pitch is dynamically adjusted based on the current shift amount: when the shift amount is small (indicating short distance), a larger pitch is used to reduce the number of shifts needed; when the shift amount is large (indicating long distance), a smaller pitch is used to maintain measurement precision. This dynamic adjustment resolves the contradiction between short distance measurement capability and processing speed.
Solution Approach 2:
The patent changes the parameter of shift pitch based on the measurement conditions. By making the pitch a variable parameter that depends on the shift amount, the system can adapt to different distance ranges. This parameter change allows the system to achieve both short distance measurement accuracy and acceptable processing speed by optimizing the number of shift operations performed.
2Productivity
If a short distance measurement limit is set to ensure processing capability, then processing load is reduced, but parallax measurement becomes impossible at closer positions
Solution Approach 1:
The patent eliminates the need for a fixed short distance measurement limit by dynamically adjusting the pitch based on the actual shift amount encountered during matching. This dynamic approach allows the system to measure parallaxes of any magnitude without being constrained by a predetermined distance limit, while still maintaining processing capability through adaptive pitch selection.
3Productivity
If the pitch for shifting blocks is increased to reduce processing time, then productivity is improved, but measurement precision for long distances deteriorates
Solution Approach 1:
The patent applies local quality by making the pitch value dependent on the local measurement conditions (shift amount). Different pitch values are used in different regions of the parallax range: larger pitches are used when small shift amounts are detected (short distances), and smaller pitches are used when large shift amounts are detected (long distances). This localized adaptation ensures both processing efficiency and measurement accuracy are maintained across all distance ranges.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A parallax calculation apparatus (12) includes an input interface (15) configured to acquire a stereo image including a first image and a second image and a controller (16) configured to calculate parallax by performing sequential matching of a block that is a portion of the second image with the first image while sequentially shifting the block from an initial position in a baseline length direction. The controller (16) varies the pitch at which the block is shifted next in accordance with the shift amount of the block from the initial position.