Posterization of Image

Posterization is an image processing method that simplifies an image by compressing its wide range of colors or tonal values into a limited number of clearly separated areas. In a normal photograph, colors transition gradually, forming smooth gradients - for example, a sunset that softly shifts from orange to yellow. After posterization, these gradual changes are removed and replaced with sharp divisions, creating visible bands or blocks of uniform color.

Studio includes a dedicated tool for the posterization of raster images, accessible via the Main Menu > Image > Tools > Posterize command.

Rather than displaying every subtle variation in hue or luminosity typical of a photograph, a posterized image simplifies these gradients into a limited number of distinct levels. This effect is comparable to transforming a photograph into a "paint-by-number" template.

Image Preprocessing

A raster image positioned in the background of the Work Area typically serves as a template for digitizing embroidery designs. Preprocessing this image can significantly accelerate the digitizing workflow, particularly for complex projects involving numerous colors.

One effective technique is to flatten image colors through posterization, providing a clear visualization of the final thread count and the layout of color segments.

Posterization merges adjacent pixels of similar color values, resulting in a simplified image structure. The intensity of this effect can be adjusted using the Amount control.

Original raster image with a full color scale. At this stage, the user must determine the number of thread colors and their placement.

Preprocessed raster image showing posterized areas of consolidated colors.

Preview

Click the Preview button to evaluate how the current posterization settings affect the image. The results will be displayed in a secondary work area on the main control panel. This preview interface allows for zooming, scrolling, and panning.

The preview area initially displays a mask until the Preview button is clicked. This mask is a monochromatic image generated from selected vector objects; black regions represent areas designated for processing, while white regions are excluded.

Mask

Converting the entire image simultaneously is not required. Studio allows the use of standard fill vector objects as a mask to isolate specific image areas for posterization. To process only a portion of the image, draw fill or column objects over the target area and select them before launching the posterization tool. The conversion will only apply to the image data beneath the selected objects. These vector objects serve as a temporary mask and can be removed once the image conversion is complete.

In this example the posterization is applied exclusively inside an area masked by a vector object. The remainder of the image remains unaffected.

Note: The Trace Tool can be used to easily generate complex mask objects.

Note: For an alternative method of simplifying image colors, consider using the Color Reduction tool.