Really hidden watermark image, audio and video PHP [closed]

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Closed 8 years ago.

How do you insert a watermark/copyright/author inside the sourcecode of the file, without making the file corrupt? Not the layer on layer method.

I have seen this on multiple videos, audios and images before so it must be possible.

Disclaimer: I already know how to put a watermark on videos and images with layer on layer method, but that is not what I am after this time.

Answer 1

Meanwhile, please view the source of an image. You'll see a lot of random text. In there you also might see clear text. But adding it yourself will make the file corrupt since it is not done properly.

That information called "Metadata". You can add Metadata to many video/audio formats. However, this data is extremely easy to remove, much easier than a visual watermark that requires retouching work. A simple re-encoding or "Open" / "Save as..." in your editor of choice will often destroy any metadata that there was.

A proper visual watermark is usually the much, much more reliable option.

If you want to continue on this path anyway, here are some related links:

For images:

• writing exif data in php
• Write EXIF into JPG with PHP

For video:

• A simple PHP class to read and write FLV meta data and cue points in Flash Video (FLV) files.
• Supplying FFmpeg With Metadata