What is the difference between watermark and no watermark?

The difference between watermarked and non-watermarked: 1. Different viewing qualities. Pictures with watermarks will cause some interference to the picture information, while pictures without watermarks have better viewing effect; 2. Different quality; 3. Purpose different.

#The operating environment of this article: Windows 7 system, Dell G3 computer.

The difference between watermark and non-watermark:

1. The viewing quality is different.

Pictures (videos) with watermarks generally cause some interference to the picture information, making it difficult for people to appreciate it.

Pictures (videos) without watermarks can fully express the content without being blocked by external text, and the viewing effect is better.

2. The quality is different.

Pictures with watermarks generally have their own original (or copyright) marks printed on them, making them difficult to steal. Such pictures can have more official authority and can better protect the integrity of the picture.

Pictures without watermarks are easy for people to use at will. Over time, if the pictures are widely circulated, the quality of the pictures will also decrease in the process of circulation.

3. Different purposes.

Pictures with watermarks are generally for official use, and the watermark should provide complete and reliable evidence of the ownership of copyright-protected information products.

The "destination" of pictures without watermarks is generally distributed online, allowing anyone to use and modify them.

Extended information:

1. The concept of watermark:

The so-called (digital) watermark is to add certain data to multimedia data (such as images, sounds, video signals, etc.) Digital information is used to achieve functions such as document authenticity identification and copyright protection. The embedded watermark information is hidden in the host file and does not affect the viewability and integrity of the original file.

2: The basic characteristics of watermarked pictures, videos, etc. are:

1. Provability

The watermark should be able to provide the ownership of information products protected by copyright. Complete and reliable evidence. The watermark algorithm identifies the owner's relevant information embedded in the protected object (such as registered user number, product logo or meaningful text, etc.) and can extract it when needed. A good watermarking algorithm should be able to provide completely uncontroversial proof of copyright, and a lot of work still needs to be done in this regard.

2. Invisibility

Imperceptibility includes two meanings. One refers to visual invisibility, that is, the changes in the image caused by embedded watermarks have a negative impact on the observer’s visual system. It should be imperceptible. The ideal situation is that the watermarked image is visually identical to the original image. This is the requirement that most watermarking algorithms should achieve.

3. Robustness

The issue of robustness is extremely important for watermarking. Robustness is a technical term. Simply put, it means that a digital watermark should be able to withstand a large number of different physical and geometric distortions, including intentional (such as malicious attacks) or unintentional (such as image compression, scanning and copying, noise pollution, dimensional changes, etc.). After these operations, a robust watermarking algorithm should still be able to extract the embedded watermark from the watermarked image or prove the existence of the watermark.

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