Noise Filter（噪声过滤器）

The purpose of Noise Filter is to clean up a noisy point cloud.

Removal

The Signal-to-Noise-Ratio (SNR) filter removes points where the SNR of the projected pattern signal is below the specified limit (see 相机捕获中可检测到的光强度). Points with low SNR values will be noisier (e.g. due to ambient light), and the SNR filter can, therefore, be used to preserve only the points that are deemed acceptable.

在一些检测应用中，可能希望仅保留高置信度的点，而在料箱拣选场景中，通常认为噪声较多的点要好于根本*没有*点，因为匹配算法将最终决定查找到的匹配信息是否通过。

Parameter	Value	Condition
Enabled	no	If you want to keep all points regardless of their SNR values (rarely)
	yes	If you want to control the quality of the point cloud by filtering out the points with low SNR values (usually)
Threshold	1	If you want to maximize the surface coverage but still filter out some points with low confidence, e.g., for Parcel Picking
	2-6	If you want to keep only decent quality points, for most applications, e.g., Manufacturing (Bin Picking) and E-commerce (Piece Picking). Use lower threshold values (2-3) to get points in the following scenes: dark parts, strong ambient light, and large distance.
	7+	If you want to keep only points with high confidence, e.g., Quality Inspection

提示

SNR threshold value of 3 yields a good tradeoff between discarded points and noise.

备注

Noise Removal (SNR) filter adds close to no additional processing time.

如需了解有关SNR值的更多信息，请参阅 SNR值。

Repair

This filter repairs the regions of missing data due to noisy points.

Value	Condition
Enabled::no	If you require all points in your point cloud to be of high confidence.
Enabled::yes	If you want to maximize the surface coverage.

备注

Noise Repair adds additional processing time. Enabling Noise Repair and Noise Suppression adds the same processing time as enabling only one of them.

Suppression

This filter reduces noise and outliers in the point cloud.

Value	Condition
Enabled::no	If you need to distinguish very fine details and thus need to avoid any smoothing effects.
Enabled::yes	If you want to reduce noise and outliers in the point cloud or reduce ripple effects caused by interreflections.

备注

Noise Suppression adds additional processing time. Enabling Noise Suppression and Noise Repair adds the same processing time as enabling only one of them.

版本历史

SDK	变更
2.10.0	Suppression and Repair filters are added.
2.0.0	添加了SNR过滤器API，替换了旧的对比度过滤器。