Download Adobe Photoshop8.0 or above. First, install it. Secondly, open the picture to be repaired under the file menu. First, copy a background layer on the toolbar on the right. Click the stamp tool on the left toolbar, move it to the side of the stained picture, select a position similar to the pixels in the stained area, hold down ALT and click the sample. Move the mouse to the stain and click to remove the stain. Two: the characters are thin; Select the layer to be repaired, click Liquefaction under the filter menu, move the first tool on the left to the place to be repaired, and you can repair it at will.