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I have noticed that on certain photos with watermarks, the watermark will show in programs like Windows Photo Viewer and Paint but not in Windows Explorer.

Here is an example photo and related thread. Here is an example of the problem as found in that thread:

example

Does this mean that the non-watermarked image can be extracted in some cases?

Zombo
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2 Answers2

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Examining the given jpeg in Windows Explorer gives no watermark in the thumbnails and a watermark in the preview screen. Further examination of the .jpeg by an exiftool shows (only relevant info showed):

ExifTool Version Number         : 9.39
File Name                       : 5.jpg
File Size                       : 129 kB
File Type                       : JPEG
Photoshop Thumbnail             : (Binary data 14603 bytes, use -b option to extract)
Thumbnail Offset                : 19234
Thumbnail Length                : 10749
Thumbnail Image                 : (Binary data 10749 bytes, use -b option to extract)

So there is a thumbnail embedded in the jpeg (in the exif/meta data) which is used by Windows Explorer (and other software).

When you open this image in Paint and save it as a different file, the thumbnail itself is not in the file anymore and your Windows Explorer thumbnail shows the watermark. (See image)

To answer the question: Yes, A (not the) non-watermarked image can be extracted but will only be 14603 or 10749 bytes in size which is probably of a lot less quality than the original.

The original (5.jpg) and saved in Paint (5b.jpg):

Images

Rik
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A quick search turned up this thread. According to the thread, LightRoom creates small watermarks in the bottom left corner of thumbnails for Explorer. This is probably to keep the smaller thumbnail from losing fidelity. Read the thread they talk about solutions.

Im curious, turn on show hidden/system files and then delete the thumbs.db file. I wonder if Windows generates the thumbnail, that the watermark from the fullsize picture will be there.

Keltari
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