Scratch Remover

Table of Contents

Scratch Remover offers the quickest answer to texture repair and defect removal in Image Doctor. Scratch Remover is a simpler-to-use counterpart to the more elaborate Smart Fill filter, and should be used to clean up minor texture defects placed in fairly homogenous surrounding textures. Use it primarily for eliminating linear defects such as tears and creases or to remove small text, such as time stamps, subtitles, or logo text from images.

Scratch Remover samples textures from areas surrounding your selection and recombines them inside your selection to organically repair images. This avoids the repetitive patterns that result from directly cloning source textures.

Before

After

This chapter contains the following sections:

Using Scratch Remover

To use Scratch Remover:

1. Select the area to be repaired.

2. Adjust the “Texture Feature Size” slider to approximately match the size of the details in the image surrounding the repair area. See the “Texture Feature Size” section for detailed information on using this slider.

3. Select the Texture Regularity setting that yields the most seamless match between the repaired area and the surrounding region.

4. Click the “Regenerate Texture” button a few times, until you find the best match result.

5. Repeat steps 2 through 4, if necessary, and click “OK.”

Slider Descriptions

Contract or Expand Selection (pixels)

Use this slider to contract or expand your original selection from within the Image Doctor interface.
Range: -20 – (20)

Why? If the initial preview reveals remnants of your original selection, you can expand your selection to knock out the leftovers. If you find that you are removing some nearby desirable image detail, you can contract your selection a couple of pixels to protect that area. It’s best to make a good, close selection before you run the filter, however.

Texture Feature Size

Use this slider to specify the texture sample size that Scratch Remover uses for texture replacement. If, for example, the blades of grass that make up the sampled texture are roughly 15 pixels tall, pump up the feature size to about 15 pixels.
Range: 3 – 30

Texture Regularity

These radio buttons control how closely Scratch Remover matches the image details generated in your selection. For more predictable textures, such as bricks, use higher values. For irregular patterns, such as grass, sometimes lower values will do just fine. Using lower Texture Regularity values helps the filter render faster and randomizes the appearance of image details generated in your selection.
Options: Low, Medium, High

Feather Radius

Feather Radius creates an opacity drop off around the edge of the affected area of your image—helping blend the filtered area with the surrounding unaffected pixels.
Range: 0 - 4 pixels.

Feathering can cause an unnatural loss of detail at the edge of your selection if used in excess.

Regenerate Texture

Use this button to randomly rearrange the fill details generated by Scratch Remover. In many cases, you can simply run the Scratch Remover filter, click “Regenerate Texture” a few times, and get great results.

Tutorials

Removing Time Codes from Photos or Video Captures

Removing time codes from photos and video captures is a snap with Image Doctor. We suggest that you use the following steps to obtain the best results.


1. Use the magic wand tool to select a single character at a time.

2. Run Scratch Remover.


3. Adjust the “Contract/Expand Selection” slider until all traces of the character have been affected.

4. Use the Texture Feature Size, Regenerate Texture button, and Feather Radius slider until you are satisfied with the background replacement.

5. Click “OK”.

6. Using the magic wand, select the next character.

7. Click Control-F, to rerun Scratch Remover with the same slider parameter combination.

8. Repeat Steps 5 and 6 until you have completely removed the time code.

Note: Keep an eye on your results. Generally, the first attempt works just fine; occasionally, however, you may need to open the filter interface and tweak the sliders to completely remove a character.

Here’s your result.

Tips and Tricks

Using Selections

Great image corrections start with good selections. Try to get a selection that includes your defect and only your defect. Specifically, we recommend that you do not use a geometric selection tool, such as Photoshop's Marquee tool to make your selections. Instead, Photoshop users can use the Lasso tool.

Using Multiple Selections on Defects Spanning Different Background Textures

To get the best results, divide your work into sections when a defect spans several visually different areas. In the example at the beginning of the chapter, a total of six selections were used to get the best result.

Removing Large Quantities of Similar Defects

When removing a large number of similar defects from an image, use the following technique to speed up your work:

  • Run the filter on an individual defect.
  • Select the remaining defects.
  • Use the filter 'redo' key (CTRL-F in Photoshop) to quickly remove the remaining defects.