Repairing a Streak Artifact in a Single Image

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This Tech Note describes a method for removing a streak artifact from a single image (see the picture below). If we had 3 or more images of the same field, the images could be registered and then median combined to remove the streak. This would work because the trail would appear in only one of the images, and would therefore be rejected by the median pixel combining method. With just one image, however, we can't use this method. To make the problem worse, atmospheric turbulence, or "seeing", makes the trail fuzzy rather than a sharp line.

One way to remove the satellite trail is to use a bad pixel "zapping" function to replace each pixel with some more reasonable value However, this would be quite impractical with so many pixels in need of repair! Mira's Blemish Repair function is designed to automatically repair bad columns, rows, and rectangular regions. But what do we do if the defect runs diagonally rather than along a column or row? This Tech Note describes a procedure that successfully corrects the defect in this image.