Multiscale window leveling CR/DX and MG images: ConceptsTopic number: 1425412830680

Multiscale window level is used to independently change the contrast and overall brightness of an image, while retaining visibility of the complete pixel range.

When interactively changing contrast and brightness of CR/DX or MG images, either window level or multiscale window level is applied, as configured in the user profile. Multiscale window level is the default setting.

Window level adjusts contrast and brightness and is applied equally to all pixel values. Changing the contrast also modifies the gray value distribution or brightness of the image and causes clipping of part of the pixel value range.

Multiscale window level adjusts contrast and brightness independently, by differentiating between coarse and fine image details, to eliminate clipping and to retain the average gray value distribution in the image. It improves the appearance of the image by increasing the contrast of the fine image details while retaining the average gray value distribution of the coarse image details, so the complete pixel range remains visible.

Compare the effect of window level and multiscale window level on a CR chest image:

An image with increased contrast using window leveling shows clipping


Regular window leveling

An image with increased contrast using multiscale window leveling does not show clipping


Multiscale window leveling

If multiscale window level is enabled in the user profile, it is applied for interactively changing contrast and brightness of any CR/DX or MG image viewed by that user.