A SCALE algorithm is available in the Algorithm Library. In some cases, you may want to use the SCALE algorithm instead of the Save As method, as it gives you more control when scaling an image by allowing you to specify your input minimum and maximum and your output minimum and maximum values. Additionally, you will be able to specify the left and right tail trimming, the scaling function, and the bit depth for the output layer.
SCALE maps the gray levels of an input image to the gray levels of an output image. The typical use of this program is to scale/quantize imagery in a high-resolution (32-bit or 16-bit) channel down to a fewer number of gray levels to fit into a low-resolution (16-bit or 8-bit) channel. SCALE can also be used to stretch or shift the dynamic range of an input image for visual enhancement.
If you have the appropriate CATALYST Professional license, you can use the SCALE program in the Algorithm Library.
Minimum and Maximum Input Gray Level Values:
If Minimum Input Gray Level Value and Maximum Input Gray Level Value are set as the default, the SCALE algorithm calculates the range from the image data based on the tail-trimming levels.
If the number of input channels is greater than one and both Minimum Input Gray Level Value and Maximum Input Gray Level Value are specified, this range is used for every input channel.
Tail Trimming:
Optionally specifies the amount of tail trimming of input image histogram before scaling. If Minimum Input Gray Level Value and Maximum Input Gray Level Value are specified, the specified input range is used, while Left Tail Trimming% and Right Tail Trimming% are ignored. If the two trimming parameters are not specified, the minimum and maximum of image data for every input channel is used for input range.
The two trimming parameters are useful only for scaling algorithms (LIN/SQR/LOG). The two quantization algorithms squeeze tails automatically.
Minimum and Maximum Output Gray Level Value:
Specifies the minimum and maximum output gray-level values after scaling. If the number of channels is greater than one, the values are used for every output channel.
Scaling Function:
Specifies the scaling function or quantization algorithm.
The following scaling functions are available, and for information about each, refer to Available scaling methods:
Specifies the sub-data type of one or more resulting images.
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