ScaleImage

ScaleImage resamples the pixels in an input image or region of interest (ROI) to produce a reduced, enlarged, unrotated or unbent version of the image. The function displays the resampled image in the upper-left corner of the In-Sight spreadsheet.

ScaleImage Inputs

Syntax: ScaleImage(Image,Fixture.Row,Fixture.Column,Fixture.Theta,Region.X,Region.Y,Region.High,Region.Wide,Region.Angle,Region.Curve,Sample Type,Sample Ratio.X Ratio,Sample Ratio.Y Ratio,Display Row,Display Column,Show)

Parameter

Description

Image

This parameter must reference a spreadsheet cell that contains an Image data structure. By default, this parameter references A0, the cell containing the AcquireImage Image data structure. This parameter can also reference other Image data structures, such as those returned by the Vision Tool Image functions. For more information, see AcquireImage and Image.

Fixture

Defines the Region of Interest (ROI) relative to a Fixture input or the output of a Vision Tool function's image coordinate system. Setting the ROI relative to a Fixture ensures that if the Fixture is rotated or translated, the ROI will be rotated or translated in relation to the Fixture. For more information, see Fixture and Vision Tools.

The default setting is (0,0,0), the top leftmost corner of the image.

Row	The row offset, in image coordinates.
Column	The column offset, in image coordinates.
Theta	The angle of orientation, in the image coordinate system.

Region

Also known as the Region of Interest (ROI), specifies the region of the image that undergoes analysis and creates a rectangular image region that can be transformed and rotated. For more information, see Interactive Graphics Mode.

Tip: With this parameter selected, you can press the Maximize Region button on the property sheet's toolbar to maximize the region and cover the entire image.

X	The x-offset of the origin, in fixture coordinates.
Y	The y-offset of the origin, in fixture coordinates.
High	The dimension along the region's x-axis.
Wide	The dimension along the region's y-axis.
Angle	The orientation, in fixture coordinates.
Curve	The angular deviation between the region's x-axis and the opposing boundary line.

Sample Type

Specifies the pixel-resampling technique.

0 = Interpolate Points (default)

Specifies using a weighted average value of the pixel region to resample the image.

Sample Ratio

Specifies the sample ratio in the (X,Y) direction of the region.

Note: Values between 100 and 1000 specify upsampling. For example, if both the ratios are specified as 200, the resampled image will be twice as large as the specified Region.

X Ratio	Specifies the ratio (10–1000; default = 50) in the X direction of the region.
Y Ratio	Specifies the ratio (10–1000; default = 50) in the Y direction of the region.

Display Row

Specifies the Row coordinate (default = 0) where the rescaled image will be displayed, relative to the upper left-hand corner.

Note:

Specifying a value of -1 will ensure that the function places the scaled image at the same row coordinate as the input image:
- For acquired images, the Start Row specified in the AcquireImage function will be used. Therefore, if a ScaleImage function is configured with a Display Row and Display Column parameter settings of 0,0, and the image was a partial acquisition, the ScaleImage function would display its output above the acquired image. For more information, see AcquireImage.
- For images output by other Vision Tools, such as an Image tool like the PointFilter function, the row coordinate that defines the input image will be used. For example, if the PointFilter function is defined at the Col/Row coordinates of 100,100, the referencing ScaleImage function with the -1 parameter setting would display at the Row coordinate of 100. For more information, see PointFilter.
For jobs created between firmware release 4.7.1 through 4.8.4 that contain a ScaleImage function, the Display Row value will be automatically set to -1 when loaded on an In-Sight vision system and/or emulator running 4.9.0 firmware. For jobs created prior to 4.7.1, the Display Row value will be automatically set to 0.

Display Column

Specifies the Column coordinate (default = 0) where the rescaled image will be displayed, relative to the upper left-hand corner.

Show

Specifies which graphical overlays are displayed on top of the image.

0 = hide all (default)	The input region boundary and resampled image will be hidden, except when the cell containing the ScaleImage function is highlighted in the spreadsheet.
1 = result graphics only	The resampled image will be displayed at all times.
2 = input graphics only	The input region boundary will be displayed at all times.

ScaleImage Outputs

Returns

An Image data structure containing the processed image, or #ERR if any of the input parameters are invalid.

ScaleImage Example

In this example, the object in the input image is a bottle. The purpose of this example is to scale the size of the bottle to 50%.

After inserting the function into the In-Sight spreadsheet, the user defines the ROI by double-clicking on the word "Region" in the property sheet, which disappears to reveal the red ROI box overlaid on the image. The user moves or resizes the box using the cursor, and clicks the OK button on the Job Edit toolbar to confirm the selection and return to the property sheet. (The selection can also be confirmed by pressing the Enter key or by double-clicking within the ROI.)

Typing "50" in both the X Scale and Y Scale fields, accepting the default settings of the other parameters and clicking OK in the property sheet completes the configuration for this example and applies the function to the input image.

Below is a 50% scaled image of the bottle.

The user can also use ScaleImage to "unbend" or "unrotate" objects, which can make it easier to reference other tools to the processed output image. In this example, the object is a slightly curved segment, which is shown with the Overlay removed (achieved by clicking Overlay on the View menu). The segment will also be scaled to 50% in size, so that both the input image and output image can easily fit in the same view.

After inserting the function, defining the ROI and specifying "50" in both the X Scale and Y Scale fields in the property sheet (described earlier in the bottle example), the user incrementally changes the values in the Angle and Curve fields under the Region parameter until the object is straight. Accepting the default settings of the other parameters and clicking OK in the property sheet completes the configuration for this example and applies the function to the input image. Below is an image of the bent object in the middle and the smaller and "unbent" version in the upper-left corner.

In this example, an angle of 17.390 and a curve of -36.389 were needed to straighten the curved segment.