Help:Removing watermarks

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Akhal Teke Stallion- Gerald (2835597069)+w.jpg Akhal Teke Stallion- Gerald (2835597069).jpg
Removing watermarks can improve the reusability of an image

Watermarked images on Commons are generally discouraged. A proposal about the acceptability of watermarked images is outlined at Commons:Watermarks.

Emblem-question-red.svg The factual accuracy of this description or the file name is disputed.
Reason: See Commons:Watermarks#Legal_issues_with_the_removal_of_watermarks

A watermark is an identifying mark added to an image, usually after creation. Digital watermarks can consist of timestamps, names, digitally added signatures, text, or an image.

Sometimes, if a version of an image without a watermark cannot be obtained from the author, it can be removed to make the image more reusable. All licenses acceptable on Commons permit this kind of modification. There are a number of ways to remove watermarks using widely-available tools, and new technology is rapidly appearing in this area. Below are a few recommended procedures.

What not to remove[edit]

Artists' signatures on paintings, captions and signatures on historic plates etcetera are not considered watermarks on Commons. The information in the text should in most cases be repeated in the image description, for example using {{original caption}}. There might be use for a version without the texts, but it should be uploaded under a separate name (see Commons:Overwriting existing files).

How to remove watermarks[edit]

If the file is labelled with the {{JPEG version of PNG}} tag, do not edit the JPEG - instead edit the original PNG file and re-save as JPEG.

In some cases, where the watermark is found in the borders of the image and the borders are unimportant, it is possible to remove the watermark by cropping it; although this loses information, it is easy and avoids any fabrication. For JPEGs, a lossless cropping tool such as JPEGCrop should be used to avoid generation loss.

Removing watermarks in Photoshop[edit]

In other cases, it is necessary to edit the image and replace the watermark with new image data. When editing JPEGs without a PNG version, it is recommended to use the BetterJPEG lossless resave plug-in for Photoshop, or a similar tool. This tool uses special knowledge of the JPEG format to losslessly resave portions of the image that are unaltered (most of the image, usually), avoiding generation loss. This is especially important with low-quality or low-resolution images. To use it, install the plug-in, then follow these steps:

  1. If editing a JPEG: Use File→Import→JPEG Lossless Import, and select the file. If not editing a JPEG, just open the file.
  2. Remove the watermark:
    • In CS5, you can use the content-aware fill tool to help you do this. Select the region containing the watermark, then choose Edit→Fill, in the "Use" drop-down choose "Content-aware", and click OK.
    • Another useful tool, available in in the same group as the Healing brush tool, is the Patch tool, which can copy a shaped region from one area of the image to another.
    • Finally, when all else fails, a useful tool to fall back on is the Clone Stamp tool, which allows you to use a brush to copy from one part of an image to another. A round, hard brush is generally best. By using different sizes of brushes and copying from different regions of the image, even complex watermarks can be removed. Sometimes, when dealing with objects like wheels with radial symmetry, changing the angle setting in the Clone Source panel can be useful.
  3. If editing a JPEG: When done, use File→Export→ JPEG Lossless Export to export the modified image. If you don't have BetterJPEG, instead re-save the JPEG at high-quality (quality level 10 or higher). If not editing a JPEG, just save.

Removing watermarks in GIMP[edit]

There is a complicated way to do this by using the freeware (no free-as-in-freedom software), proof-of-concept-quality Jpegjoin tool along with the immortal GIMP. You edit and recompress the parts of the image that need to be changed and assemble them with losslessly processed parts of the original file using Jpegjoin.

Among other shortcomings in the usability of Jpegjoin, you can only assemble equally sized parts seamlessly. Otherwise it will be padding the individual parts by appending uniform grey blocks to make them fit the biggest of the bunch. Use either Jpegjoin or its more comfortable cousin, Jpegcrop, to slice the original file to parts that may be assembled seamlessly in Jpegjoin. You'll have to first slice vertically to equally sized pieces, then pick the piece containing the part to edit and slice it horizontally to equally sized pieces, for example. You may need several slicing-and-joining sessions and complex slicing strategies, of course…

For the (re)compression of the edited part you have to at least use the same colour subsampling setting as the original file and maybe it's a good idea to use the exactly same compression settings that were used to produce the original file; GIMP has an option for that.

Jpegjoin can be run on Linux in Wine.

Removing watermarks in Inpaint[edit]

There is easy solution to remove watermark using Inpaint. You just need to mark watermark area and run automatically process, which restore selected area using surrounding data.

Removing invisible digital watermarks[edit]

Invisible digital watermarks, such as those embedded by the Digimarc Photoshop plug-in can be very difficult to remove. Cropping, resizing, adding noise, and even moderate blurring will usually fail to remove the watermark. For black and white photographs or monochrome prints that are saved with an RGB color palette, however, it is often possible to remove the watermark by converting the image to grayscale. If the original image was sepia-toned, you can convert back to RGB and colorize the image as appropriate. Removing invisible digital watermarks should only be done if it is non-destructive to the image.

See also[edit]