# Choose an Image Normalization Mode

An OCRMax tool performs image normalization on the region of interest and generates an internal range of intensity values in order to improve the process of distinguishing character pixels from background pixels.

By default the OCRMax tool is configured to allow significant variation in both background pixels and character pixels, as shown in the following example image:

Use the NormalizationMode property to specify the type of image normalization the OCRMax tool will perform as it differentiates character pixels from background pixels. Choosing the right value can reduce the execution time of the tool. Choose from the following options:

Value | When To Use
--- | ---
LocalAdvanced | Use the default when the pixels in both the background and the character string can show significant variation within the region of interest. Of all the options, this one has the greatest impact on the execution speed of the OCRMax tool.
Local | Use when the background can show significant variation but the print quality of the character string remains constant.
Global | Appropriate for high-quality images where there is little background noise and no lighting variation across the region of interest
None | Performs no image normalization and relies on a specific grey value as the threshold between character pixels and background pixels. See the section Determine a Foreground Threshold for more information about how the OCRMax tool calculates this grey value. This option has the least effect on execution speed.