Edit Pixel Mask


The Edit Pixel Mask command is used to view or input the coordinates of bad pixels A bad pixel list is used by the Apply Pixel Mask command to repair isolated hot and cold pixels (to learn more, see Working with Pixel Masks, below). The Pixel Mask Editor contains a data grid that lists pixel coordinates. Use this tool to create new pixel masks or to review and edit masks created using the Create Pixel Mask command. If working with defects larger than isolated pixels, consider workign with a blemish mask (see the Edit Blemish Mask and Apply Blemish Mask commands).

The dialog above shows 2 bad pixels at coordinates (1,10) and (400,2000). These data were loaded from the file test.pxm. After changing the pixel descriptions or adding new ones, the mask can be saved back to its file or to a new file. Entries in the Notes column are optional.

Editing Pixel Masks

The Pixel Mask Editor contains a data grid that lists the (column,row) coordinates of each mask location. The currently loaded pixel mask file is named in the edit field at the top of the window. Pixel mask files have a .pxm. file name extension. Several important commands related to the data grid are located in a right-click context menu.

To Create a New Mask:
To Edit an Existing Mask:

Saving Changes

When you are finished entering data for a pixel mask, save using one of these methods:

Working with Pixel Masks

In the context of cosmetic repairs, a pixel mask is a collection of point coordinates that describe bad pixel locations in an image. When a pixel mask is applied to an image, the value at each mask coordinate is replaced by a value obtained from the neighboring pixels. This technique is used to repair defective pixels or "hot" pixels caused by thermal noise in CCD images. If the bad pixel locations do not change, then the same mask can be used for many images on different occasions.

A Pixel Mask is usually stored in a file with a pxm extension, like Pixel-mask.pxm, although txt or any other extension is possible. Each line describes the coordinates of 1 pixel. The Notes column holds an optional comment.

Note

Remember that coordinates in Mira are 1-based, meaning that pixel (1,1) is the origin of the image array. See Image Coordinate System and Pixel Coordinate Definition.

Related Topics

Create Pixel Mask, Apply Pixel Mask, Edit Blemish Mask, Clean Image Set, Image Calibration, Image Coordinate System