# Automatic Registration of Multi-Projector Based on Coded Structured Light

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## Abstract

**:**

## 1. Introduction

## 2. Geometric Registration Principle

#### 2.1. Coordinate System

#### 2.2. Consistency of Geometric Correction

- When ${\mu}^{E}\left(x\right)$ remains unchanged, for each point on the screen $S$ and on the image plane ${\pi}_{E}$, the geometric error is determined and only related to the structural parameters of the multi-projector system, not to the virtual scene (consistency of geometric correction).

## 3. Geometric Correction

#### 3.1. Geometric Distortion Correction

#### 3.2. Geometric Description of Screen

#### 3.2.1. Feature Points

#### 3.2.2. Edge Detection for RBGC

#### 3.2.3. Three-Dimensional Reconstruction

#### 3.3. Geometric Description of Projector

## 4. Results

#### 4.1. Feature Points Identification Result

#### 4.2. Geometric Registration Result

## 5. Discussion

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 7.**The center location of the sphere. (

**a**) Center calculated by black-white gray code (BWGC); (

**b**) center calculated by RBGC.

**Figure 8.**Normal probability plot diagram for the distance between the measured spherical center and the physical spherical center. (

**a**) Distance obtained from BWGC; (

**b**) distance obtained from RBGC.

**Figure 9.**Result of a two-dimensional multi-projection mosaic. (

**a**) Multi-projector system before geometric registration; (

**b**) multi-projector system after geometric registration.

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**MDPI and ACS Style**

Zhao, S.; Zhao, M.; Dai, S.
Automatic Registration of Multi-Projector Based on Coded Structured Light. *Symmetry* **2019**, *11*, 1397.
https://doi.org/10.3390/sym11111397

**AMA Style**

Zhao S, Zhao M, Dai S.
Automatic Registration of Multi-Projector Based on Coded Structured Light. *Symmetry*. 2019; 11(11):1397.
https://doi.org/10.3390/sym11111397

**Chicago/Turabian Style**

Zhao, Shuaihe, Mengyi Zhao, and Shuling Dai.
2019. "Automatic Registration of Multi-Projector Based on Coded Structured Light" *Symmetry* 11, no. 11: 1397.
https://doi.org/10.3390/sym11111397