Image Format Control

Region Of Interest

An image region of interest (ROI) lets you specify a portion of the image so that after each image is acquired only the pixel information from the specified portion is processed.

Use the following features to specify the location and size of the ROI. All values are in pixels.

OffsetX - Horizontal offset from the origin to the ROI.

Width - Width of the image provided by the device. This reflects the current ROI. The maximum value of this feature takes into account horizontal binning, decimation, or any other function changing the maximum horizontal dimensions of the image and is typically equal to WidthMax minus OffsetX.

OffsetY - Vertical offset from the origin to the ROI.

Height - Height of the image provided by the device. This reflects the current ROI. The maximum value of this feature takes into account vertical binning, decimation, or any other function changing the maximum vertical dimensions of the image and is typically equal to HeightMax minus OffsetY.

Binning/Decimation

Binning refers to the act of combining the signal from groups of photo-sensitive cells into a larger logical pixel. This is achieved by either adding (additive), averaging (average), or discarding (discard). Binning may be implemented in analog by the sensor or digitally by the Image Signal Processing engine (ISP).

Note: Binning and Decimation cannot operate simultaneously. For one to be active, the other must be inactive. Changes to binning features can only be made while the camera is not streaming.

Use the BinningSelector to choose the binning engine. This affects both horizontal and vertical binning. The choices are:

All - the total amount of binning. In this mode, the camera adjusts the sensor/ISP binning to achieve the best image quality with the fastest frame rate.

Sensor - the portion of binning implemented in analog by the sensor. Binning done by the sensor usually results in a higher frame rate. Unless otherwise specified, or unsupported, binning is done by the sensor by default.

ISP - the portion of binning implemented digitally by the ISP. Unless otherwise specified, binning is done by the ISP if sensor binning is is unsupported or compromises image quality.

Use BinningHorizontalMode and BinningVerticalMode to choose the algorithm to perform the combination. The choices are:

Additive - The response from the combined cells are added, resulting in increased sensitivity (a brighter image).

Average - The response from the combined cells are averaged, resulting in increased signal to noise ratio. Some sensors do not support average binning.

Use BinningHorizontal and BinningVertical to set the number of cells to combine. Binning values reduce the resolution of the image by a corresponding factor. A value of 1 indicates no binning. This must be set to 1 for decimation to be active.

Use DecimationSelector to choose the decimation engine. The choices are All or Sensor. Decimation cannot be done by the ISP.

DecimationHorizontalMode and DecimationVerticalMode indicate the algorithm to perform the reduction. There is only one decimation mode supported: Discard.

Use DecimationHorizontal and DecimationVertical to set the number of cells to discard. This value reduces the resolution of the image by only retaining a single pixel within a window whose size is the specified decimation factor. A value of 1 indicates no decimation. This must be set to 1 for binning to be active.

Binning/Decimation Feature Dependency

There are many feature dependencies which can affect binning. You can disable the ISP engine which would force all binning to be sensor controlled. However, some pixel formats (such as YUV and RGB) do not allow the ISP to be disabled, as it is required for color interpolation. In addition, not all sensors support average binning.

A simple hierarchical organization of the features means that features higher up have the greatest flexibility. Choices made at the top of the hierarchy adjust features downstream. The camera always attempts to achieve the best possible image quality.

Pixel Format

Format of the pixel provided by the camera. Use PixelFormat feature to select from a list of supported formats. (Not all formats are supported on all cameras.) Once a format is selected, the following values are derived:

PixelSize provides the total size in bits of the image's pixel.

PixelColorFilter is the type of color filter that is applied to the image. This only applies to bayer formats. The value is None for other formats.

PixelDynamicRangeMin is the minimum value that can be returned during the digitization process. This corresponds to the darkest value of the camera. For color cameras, this returns the smallest value that each color component can take.

PixelDynamicRangeMax is the maximum value that can be returned during the digitization process. This corresponds to the brightest value of the camera. For color cameras, this returns the largest value that each color component can take.

Note: For color cameras, the bayer pixel format is updated if Reverse X and Reverse Y are changed. For example, if the original pixel format is BayerRG8 and Reverse X is switched from Disabled to Enabled, then the pixel format is updated to BayerGR8.

Single Channel 8-bit and 16-bit Formats

8-bit Formats Mono8 8-bit monochrome packed format
BayerGR8 8-bit bayer green red packed format
BayerRG8 8-bit bayer red green packed format
BayerGB8 8-bit bayer green blue packed format
BayerBG8 8-bit bayer blue green packed format
16-bit Formats Mono16 16-bit monochrome packed format
BayerGR16 16-bit bayer green red packed format
BayerRG16 16-bit bayer red green packed format
BayerGB16 16-bit bayer green blue packed format
BayerBG16 16-bit bayer blue green packed format

Single Channel 12-bit Formats

12-bit pixel formats have two different packing formats as defined by USB3 Vision and GigE Vision. Note: the packing format is not related to the interface of the camera. Both may be available on USB3 or GigE devices.

The USB3 Vision method is designated with a p. It is a 12-bit format with its bit-stream following the bit packing method illustrated in Figure 1. The first byte of the packed stream contains the eight least significant bits (lsb) of the first pixel. The third byte contains the eight most significant bits (msb) of the second pixel. The four lsb of the second byte contains four msb of the first pixel, and the rest of the second byte is packed with the four lsb of the second pixel.

This packing format is applied to: Mono12p, BayerGR12p, BayerRG12p, BayerGB12p and BayerBG12p.

Figure 1. Packing two 12-bit pixels into three bytes.

The GigE Vision method is designated with Packed. It is a 12-bit format with its bit-stream following the bit packing method illustrated in Figure 2. The first byte of the packed stream contains the eight msb of the first pixel. The third byte contains the eight msb of the second pixel. The four lsb of the second byte contains four lsb of the first pixel, and the rest of the second byte is packed with the four lsb of the second pixel.

This packing format is applied to: Mono12Packed, BayerGR12Packed, BayerRG12Packed, BayerGB12Packed and BayerBG12Packed.

Figure 2. Packing two 12-bit pixels into three bytes.

Multi-Channel Formats

For the following pixel formats, the color channels are packed in the order indicated:

RGB8Packed 8-bit red-green-blue packed format
BGR8 8-bit blue-green-red packed format
BGRa8 8-bit blue-green-red-alpha packed format

For YCbCr and YUV pixel formats, the RGB to YCbCr transformation follows Equation 1 below:

Y' = 0.299 R' + 0.587 G' + 0.114 B'
Cb = -0.16874 R' 0.33126 G' + 0.5000 B' + 128
Cr = 0.5000 R' 0.41869 G' 0.08131 B' + 128

YCbCr8 / YUV444Packed

8-bit Y-Cb-Cr 4:4:4 format (Figure 3). No sub-sampling on Y, Cb or Cr. The values of Y, Cb and Cr cover the full range from 0 to 255 if the input R, G and B values are in the range of [0, 255].

Figure 3. Y-Cb-Cr 4:4:4 format.

Figure 4. Packing format for YCbCr8.


Figure 5. Packing format for YUV444Packed.

YCbCr422_8 / YUV422Packed

8-bit Y-Cb-Cr 4:2:2 format (Figure 6). No sub-sampling on Y. Cb and Cr are sub-sampled by a factor of 2 in the horizontal direction, but no sub-sampling in the vertical direction. The values of Y, Cb and Cr cover the full range from 0 to 255 if the input R, G and B values are in the range of [0, 255].

Figure 6. Y-Cb-Cr 4:2:2 format.


Figure 7. Packing format for YCbCr422_8.

Figure 8. Packing format for YUV422Packed.

YCbCr411_8 / YUV411Packed

8-bit Y-Cb-Cr 4:1:1 format (Figure 9). No sub-sampling on Y. Cb and Cr are sub-sampled by a factor of 4 in the horizontal direction, but no sub-sampling in the vertical direction. The values of Y, Cb and Cr cover the full range from 0 to 255 if the input R, G and B values are in the range of [0, 255].

Figure 9. Y-Cb-Cr 4:1:1 format.

Figure 10. Packing format for YCbCr411_8.

Figure 12. Packing format for YUV411Packed.

ADC Bit Depth

All camera sensors incorporate an analog to digital converter (ADC) to digitize the images.

The camera's ADC is configured to a fixed bit output. This is not the same as pixel size. If the pixel format selected has fewer bits per pixel than the ADC output, the least significant bits are dropped. If the pixel format selected has greater bits per pixel than the ADC output, the least significant bits are padded and can be discarded by the user. Image data is left-aligned across a 2-byte format.

For example, for a 12-bit output, the least significant 4 bits are padded in order to fill 2 bytes (0xFFF0).

A 10-bit conversion produces 1,024 possible values between 0 and 65,472.

A 12-bit conversion produces 4,096 possible values between 0 and 65,520.

A 14-bit conversion produces 16,384 possible values between 0 and 65,532.

Some image sensors support multiple ADC bit depths. A higher ADC bit depth results in better image quality but slower maximum frame rate. Stop acquisition then use the ADC Bit Depth control to make a selection.

Test Pattern

The camera is capable of outputting continuous static images for testing and development purposes.

Use the TestPatternGeneratorSelector feature to choose which test pattern to control.

Sensor produces a test pattern that varies based on the image sensor.

Pipeline Start inserts a test pattern at the start of the camera's image processing pipeline.

Set the TestPattern feature to Off to disable the selected test pattern generator.

When Sensor is selected, create a test pattern by setting the TestPattern feature to Sensor Test Pattern.

When Pipeline Start is selected, create a test pattern by setting the TestPattern feature to Increment or Variable Frame Sequence. The Increment test pattern increases the pixel value by one 8-bit greyscale value at each pixel location, wrapping around to zero after it reaches 255.

The Variable Frame Sequence option generates a sequence of frames containing varying test pattern. The sequence resets at the start of acquisition.

Both test pattern generators can be enabled at the same time, however, the Pipeline Start test pattern overwrites the Sensor test pattern.

Most image processing features (such as Gamma, Balance Ratio, and others) are still available when the test pattern is on and can alter the test pattern image. Some features for controlling the sensor do not affect the test pattern image, such as Exposure Time, Gain, and analog Black Level. It is recommended to turn Exposure Auto and Gain Auto Off when using a test pattern, as those features do not function properly when the test pattern is on.

Note that the test pattern generators must be set to Off to get the actual image data from the sensor.

Reverse X

When Reverse X is enabled, it horizontally flips the image sent by the camera. The region of interest is applied after flipping.

For color cameras, the bayer pixel format may be changed after flipping. For example, BayerRG16 is changed to BayerGR16.

Reverse Y

When Reverse Y is enabled, it vertically flips the image sent by the camera. The region of interest is applied after flipping.

For color cameras, the bayer pixel format may be changed after flipping. For example, BayerRG16 is changed to BayerGB16.

Summary Table

Name Interface Access Visibility Description
Sensor Width IInteger RO Expert Effective width of the sensor in pixels.
Sensor Height IInteger RO Expert Effective height of the sensor in pixels.
Width Max IInteger Expert Maximum width of the image (in pixels). The dimension is calculated after horizontal binning. WidthMax does not take into account the current Region of interest (Width or OffsetX).
Height Max IInteger Expert Maximum height of the image (in pixels). This dimension is calculated after vertical binning. HeightMax does not take into account the current Region of interest (Height or OffsetY).
Width IInteger Beginner Width of the image provided by the device (in pixels).
Height IInteger Beginner Height of the image provided by the device (in pixels).
Offset X IInteger Beginner Horizontal offset from the origin to the ROI (in pixels).
Offset Y IInteger Beginner Vertical offset from the origin to the ROI (in pixels).
Pixel Format IEnumeration Beginner Format of the pixel provided by the camera.
Pixel Size IEnumeration RO Expert Total size in bits of a pixel of the image.
Pixel Color Filter IEnumeration RO Expert Type of color filter that is applied to the image. Only applies to Bayer pixel formats. All others have no color filter.
Pixel Dynamic Range Min IInteger RO Expert Minimum value that can be returned during the digitization process. This corresponds to the darkest value of the camera. For color cameras, this returns the smallest value that each color component can take.
Pixel Dynamic Range Max IInteger RO Expert Maximum value that can be returned during the digitization process. This corresponds to the brightest value of the camera. For color cameras, this returns the biggest value that each color component can take.
ISP Enable IBoolean RW Expert Controls whether the image processing core is used for optional pixel format mode (i.e. mono).
Binning Selector IEnumeration Beginner Selects which binning engine is controlled by the BinningHorizontal and BinningVertical features.
Binning Horizontal Mode [Binning Selector] IEnumeration Expert
Binning Vertical Mode [Binning Selector] IEnumeration Expert
Binning Horizontal [Binning Selector] IInteger Beginner Number of horizontal photo-sensitive cells to combine together. This reduces the horizontal resolution (width) of the image. A value of 1 indicates that no horizontal binning is performed by the camera. This value must be 1 for decimation to be active.
Binning Vertical [Binning Selector] IInteger Beginner Number of vertical photo-sensitive cells to combine together. This reduces the vertical resolution (height) of the image. A value of 1 indicates that no vertical binning is performed by the camera. This value must be 1 for decimation to be active.
Decimation Selector IEnumeration Beginner Selects which decimation layer is controlled by the DecimationHorizontal and DecimationVertical features.
Decimation Horizontal Mode [Decimation Selector] IEnumeration Expert The mode used to reduce the horizontal resolution when DecimationHorizontal is used. The current implementation only supports a single decimation mode: Discard. Average should be achieved via Binning.
Decimation Vertical Mode [Decimation Selector] IEnumeration Expert The mode used to reduce the vertical resolution when DecimationVertical is used. The current implementation only supports a single decimation mode: Discard. Average should be achieved via Binning.
Decimation Horizontal [Decimation Selector] IInteger Beginner Horizontal decimation of the image. This reduces the horizontal resolution (width) of the image by only retaining a single pixel within a window whose size is the decimation factor specified here. A value of 1 indicates that no horizontal decimation is performed by the camera. This value must be 1 for binning to be active.
Decimation Vertical [Decimation Selector] IInteger Beginner Vertical decimation of the image. This reduces the vertical resolution (height) of the image by only retaining a single pixel within a window whose size is the decimation factor specified here. A value of 1 indicates that no vertical decimation is performed by the camera. This value must be 1 for binning to be active.
Reverse X IBoolean RW Expert Horizontally flips the image sent by the device. The region of interest is applied after flipping. For color cameras the bayer pixel format is affected. For example, BayerRG16 changes to BayerGR16.
Reverse Y IBoolean RW Expert Vertically flips the image sent by the device. The region of interest is applied after flipping. For color cameras the bayer pixel format is affected. For example, BayerRG16 changes to BayerGB16.
Test Pattern Generator Selector IEnumeration Selects which test pattern generator is controlled by the TestPattern feature.
Test Pattern [Test Pattern Generator Selector] IEnumeration Selects the type of test pattern that is generated by the device as image source.
ADC Bit Depth IEnumeration Beginner Selects which ADC bit depth to use. A higher ADC bit depth results in better image quality but slower maximum frame rate.

Image Format Control Features


Sensor Width

Effective width of the sensor in pixels.

Property Value
Name SensorWidth
Interface IInteger
Access RO
Unit
Visibility Expert
Value 4096

Sensor Height

Effective height of the sensor in pixels.

Property Value
Name SensorHeight
Interface IInteger
Access RO
Unit
Visibility Expert
Value 3008

Width Max

Maximum width of the image (in pixels). The dimension is calculated after horizontal binning. WidthMax does not take into account the current Region of interest (Width or OffsetX).

Property Value
Name WidthMax
Interface IInteger
Access
Unit
Visibility Expert

Height Max

Maximum height of the image (in pixels). This dimension is calculated after vertical binning. HeightMax does not take into account the current Region of interest (Height or OffsetY).

Property Value
Name HeightMax
Interface IInteger
Access
Unit
Visibility Expert

Width

Width of the image provided by the device (in pixels).

Property Value
Name Width
Interface IInteger
Access
Unit
Visibility Beginner

Height

Height of the image provided by the device (in pixels).

Property Value
Name Height
Interface IInteger
Access
Unit
Visibility Beginner

Offset X

Horizontal offset from the origin to the ROI (in pixels).

Property Value
Name OffsetX
Interface IInteger
Access
Unit
Visibility Beginner

Offset Y

Vertical offset from the origin to the ROI (in pixels).

Property Value
Name OffsetY
Interface IInteger
Access
Unit
Visibility Beginner

Pixel Format

Format of the pixel provided by the camera.

Property Value
Name PixelFormat
Interface IEnumeration
Access
Visibility Beginner

Enumeration Values
Mono8
Mono16
RGB8Packed
BayerGR8
BayerRG8
BayerGB8
BayerBG8
BayerGR16
BayerRG16
BayerGB16
BayerBG16
Mono12Packed
BayerGR12Packed
BayerRG12Packed
BayerGB12Packed
BayerBG12Packed
YUV411Packed
YUV422Packed
YUV444Packed
Mono12p
BayerGR12p
BayerRG12p
BayerGB12p
BayerBG12p
YCbCr8
YCbCr422_8
YCbCr411_8
BGR8
BGRa8

Pixel Size

Total size in bits of a pixel of the image.

Property Value
Name PixelSize
Interface IEnumeration
Access RO
Visibility Expert

Enumeration Values
Bpp1
Bpp2
Bpp4
Bpp8
Bpp10
Bpp12
Bpp14
Bpp16
Bpp20
Bpp24
Bpp30
Bpp32
Bpp36
Bpp48
Bpp64
Bpp96

Pixel Color Filter

Type of color filter that is applied to the image. Only applies to Bayer pixel formats. All others have no color filter.

Property Value
Name PixelColorFilter
Interface IEnumeration
Access RO
Visibility Expert

Enumeration Values
None
BayerRG
BayerGB
BayerGR
BayerBG

Pixel Dynamic Range Min

Minimum value that can be returned during the digitization process. This corresponds to the darkest value of the camera. For color cameras, this returns the smallest value that each color component can take.

Property Value
Name PixelDynamicRangeMin
Interface IInteger
Access RO
Unit
Visibility Expert
Value 0

Pixel Dynamic Range Max

Maximum value that can be returned during the digitization process. This corresponds to the brightest value of the camera. For color cameras, this returns the biggest value that each color component can take.

Property Value
Name PixelDynamicRangeMax
Interface IInteger
Access RO
Unit
Visibility Expert

ISP Enable

Controls whether the image processing core is used for optional pixel format mode (i.e. mono).

Property Value
Name IspEnable
Interface IBoolean
Access RW
Visibility Expert

Binning Selector

Selects which binning engine is controlled by the BinningHorizontal and BinningVertical features.

Property Value
Name BinningSelector
Interface IEnumeration
Access
Visibility Beginner

Enumeration Values
All
Sensor
ISP

Binning Horizontal Mode

Property Value
Name BinningHorizontalMode [Binning Selector]
Interface IEnumeration
Access
Visibility Expert

Enumeration Values
Sum
Average

Binning Vertical Mode

Property Value
Name BinningVerticalMode [Binning Selector]
Interface IEnumeration
Access
Visibility Expert

Enumeration Values
Sum
Average

Binning Horizontal

Number of horizontal photo-sensitive cells to combine together. This reduces the horizontal resolution (width) of the image. A value of 1 indicates that no horizontal binning is performed by the camera. This value must be 1 for decimation to be active.

Property Value
Name BinningHorizontal [Binning Selector]
Interface IInteger
Access
Unit
Visibility Beginner

Binning Vertical

Number of vertical photo-sensitive cells to combine together. This reduces the vertical resolution (height) of the image. A value of 1 indicates that no vertical binning is performed by the camera. This value must be 1 for decimation to be active.

Property Value
Name BinningVertical [Binning Selector]
Interface IInteger
Access
Unit
Visibility Beginner

Decimation Selector

Selects which decimation layer is controlled by the DecimationHorizontal and DecimationVertical features.

Property Value
Name DecimationSelector
Interface IEnumeration
Access
Visibility Beginner

Enumeration Values
All
Sensor

Decimation Horizontal Mode

The mode used to reduce the horizontal resolution when DecimationHorizontal is used. The current implementation only supports a single decimation mode: Discard. Average should be achieved via Binning.

Property Value
Name DecimationHorizontalMode [Decimation Selector]
Interface IEnumeration
Access
Visibility Expert

Enumeration Values
Discard

Decimation Vertical Mode

The mode used to reduce the vertical resolution when DecimationVertical is used. The current implementation only supports a single decimation mode: Discard. Average should be achieved via Binning.

Property Value
Name DecimationVerticalMode [Decimation Selector]
Interface IEnumeration
Access
Visibility Expert

Enumeration Values
Discard

Decimation Horizontal

Horizontal decimation of the image. This reduces the horizontal resolution (width) of the image by only retaining a single pixel within a window whose size is the decimation factor specified here. A value of 1 indicates that no horizontal decimation is performed by the camera. This value must be 1 for binning to be active.

Property Value
Name DecimationHorizontal [Decimation Selector]
Interface IInteger
Access
Unit
Visibility Beginner

Decimation Vertical

Vertical decimation of the image. This reduces the vertical resolution (height) of the image by only retaining a single pixel within a window whose size is the decimation factor specified here. A value of 1 indicates that no vertical decimation is performed by the camera. This value must be 1 for binning to be active.

Property Value
Name DecimationVertical [Decimation Selector]
Interface IInteger
Access
Unit
Visibility Beginner

Reverse X

Horizontally flips the image sent by the device. The region of interest is applied after flipping. For color cameras the bayer pixel format is affected. For example, BayerRG16 changes to BayerGR16.

Property Value
Name ReverseX
Interface IBoolean
Access RW
Visibility Expert

Reverse Y

Vertically flips the image sent by the device. The region of interest is applied after flipping. For color cameras the bayer pixel format is affected. For example, BayerRG16 changes to BayerGB16.

Property Value
Name ReverseY
Interface IBoolean
Access RW
Visibility Expert

Test Pattern Generator Selector

Selects which test pattern generator is controlled by the TestPattern feature.

Property Value
Name TestPatternGeneratorSelector
Interface IEnumeration
Access
Visibility

Enumeration Values
Sensor
PipelineStart

Test Pattern

Selects the type of test pattern that is generated by the device as image source.

Property Value
Name TestPattern [Test Pattern Generator Selector]
Interface IEnumeration
Access
Visibility

Enumeration Values
Off
Increment
SensorTestPattern

ADC Bit Depth

Selects which ADC bit depth to use. A higher ADC bit depth results in better image quality but slower maximum frame rate.

Property Value
Name AdcBitDepth
Interface IEnumeration
Access
Visibility Beginner

Enumeration Values
Bit8
Bit10
Bit12