Sampling (2D)

Color

Setting Settings2D::Sampling::Color to rgb or grayscale specifies the type of information that can be captured from the scene. Depending on camera model the setting will have different options.

Available Settings2D::Sampling::Color values

	Zivid 2/2+	Zivid 2+ R
rgb	✓	✓
grayscale		✓

The behavior of different capture functions in relation to Settings2D::Sampling::Color is as follows:

Capture2D3D() and Capture2D()

• Acquire full color information when Settings2D::Sampling::Color is set to rgb.

• Acquire texture or intensity information when Settings2D::Sampling::Color is set to grayscale.

Capture3D()

• Does not acquire color or texture information, regardless of the Settings2D::Sampling::Color setting.

• Assigns uniform RGB values (\(R=200\), \(G=50\), and \(B=200\)) to all pixels, resulting in a pink image and point cloud.

Result of combination of available capture functions and Settings2D::Sampling::Color options

Capture function	Settings2D::Sampling::Color	2D image	Point cloud
Capture2D3D()	rgb	RGB	RGB
	grayscale	Grayscale	Grayscale
	__not_set__	RGB	RGB
Capture2D()	rgb	RGB	/
	grayscale	Grayscale	/
	__not_set__	RGB	/
Capture3D()	rgb	Pink	Pink
	grayscale	Pink	Pink
	__not_set__	Pink	Pink

Point cloud is in color when Capture2D3D() is used with Settings2D::Sampling::Color set to rgb	Point cloud is in grayscale when Capture2D3D() is used with Settings2D::Sampling::Color set to grayscale	Point cloud is in pink when Capture3D() is used, regardless of Settings2D::Sampling::Color

2D image is in color when Capture2D3D() or Capture2D() is used with Settings2D::Sampling::Color set to rgb	2D image is in grayscale when Capture2D3D() or Capture2D() is used with Settings2D::Sampling::Color set to grayscale	2D image is in pink when Capture3D() is used, regardless of Settings2D::Sampling::Color

Pixel

The Settings2D::Sampling::Pixel parameter is used to choose the sampled pixels to generate 2D image. Depending on camera model the setting will have different options.

Available Sampling::Pixel values

	Zivid 2/2+	Zivid 2+ R
all	✓	✓
by2x2		✓
by4x4		✓
blueSubsample2x2	✓
redSubsample2x2	✓
blueSubsample4x4	✓
redSubsample4x4	✓

The respective resolutions, given camera, are as follows:

3D capture resolutions

3D capture	Zivid 2+	Zivid 2
Full resolution [1]	2448 x 2048	1944 x 1200
2x2 [1]	1224 x 1024	972 x 600
4x4 [1]	612 x 512	Not available

[1] (1,2,3)

2D information extracted from the 3D data will have same resolution.

When set to all, all pixels sampled, and the 2D image has full resolution.

The following illustration shows the sensor grid and associated indices.

When we sub-/downsample (2x2) we get 1/4 of the original number of pixels.

This means that, after subsampling or downsampling 2x2, the number of pixels along x and y axis is divided by 2. For subsample 4x4 the number of points along x and y axis is divided by 4.

As an example see the zoomed-in sections of three images of the same scene, each captured with different Settings2D::Sampling::Pixel setting.

all	by2x2	by4x4

Subsampling decreases the acquisition and capture time, as less data will be captured and processed. Additionally, it eliminates the need to downsample the data to transform it to a more manageable size and thus reduces the storage and post-processing requirements. With a quarter of the data, user post-processing (e.g., AI based segmentation) become faster.