Labeling Techniques for Image Protection

The following are examples of labeling techniques soley for the purpose of identifying the repository which owns the image in such away that it would inhibit their unauthorized use. I have provided two examples of possible techniques. One is to provide the name of the repository in a prominent location and in an easily read font. The other example used a smaller font in a color just slightly different from the dominant background color. While not as noticable, it is just apparent enough to mar the image. It is, in fact, ledgible under close examination. These two techniques could be used alone or together.

While any of these labels could be removed using an image processing software such as Photoshop, it is unlikely that most people will have such software at their disposal. Furthermore, the more the labelling intrudes into the body of the image, the more difficult a nd time consuming it will be to remove (see examples 1 and 2). Where I have used more prominent labeling (examples 3 and 4) the possibility for removal is much greater.

Another possibility is to make the labelling as intrusive as possible without obscuring valuable information. See example 5.

To view examples where I have labelled smaller black and white images with more detail see images 6-8 below.

I came to the conclusion that the method offering the most potential for preventing or dicouraging unauthorized or illegal further use of digital images is to use a combination of techniques. The bolder label offers ledgible information about the image while the less readable one acts as a watermark (example 1).



Image 1

Scanner: HP ScanJet IIc
Scan type: Color Photo
Scanned at: 72 dpi
Mode: RGB Color
Saved format: JPEG (medium quality)
File size: 38K

Labeling Method: The name of the Repository applied with Photoshop 3.0 in two locations:

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Image 2

Scanner: HP ScanJet IIc
Scan type: Sharp Color Photo
Scanned at: 72 dpi
Mode: RGB Color
Saved format: JPEG (medium quality)
File size: 23K

Labeling Method: The name of the repository applied with Photoshop 3.0 in one location:

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Image 3

Scanner: HP ScanJet IIc
Scan type: Millions of Colors
Scanned at: 72 dpi
Mode: RGB Color
Saved format: JPEG (medium quality)
File size: 11K

Labeling Method: The name of the repository applied with Photoshop 3.0 in one location:

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Image 4

Scanner: HP ScanJet IIc
Scan type:Sharp Millions of Colors
Scanned at: 72 dpi
Mode: RGB Color
Saved format: JPEG (medium quality)
File size: 12K

Labeling Method:

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Image 5

Scanner: HP ScanJet IIc
Scan type:Sharp Millions of Colors
Scanned at: 72 dpi
Mode: RGB Color
Saved format: JPEG (medium quality)
File size:10K

Labeling Method: The name of the repository applied with Photoshop 3.0 in one location:

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Below are three identical black and white images from the Labadie Collection. Here I wanted to illustrate the same methods exhibited in the previous examples, but this time using an image without a substantial border. Labeling images containing a lot of information is more problematic. The point of this type of labeling is to provide a property stamp that is difficult to remove, but does not obscure information that is of interest to the viewer using this material.

Images 6-8

Scanner: HP ScanJet 3c
Scan type: Sharp Black and White photo
Scanned at: 72 dpi
Mode: Grayscale
Saved format: JPEG (medium quality)
File size: 12K

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Cameron Trowbridge
cambridg@umich.edu