ScanMom studio pictures have recently been doing research to play a watermark, image watermark is a very good fight against Daolian way, even if you picture was reproduced, with your website logo is a good means of publicity.
I am not a programmer universal use GD library, but the method of ImageMagic software, you can go to the official website to download to use, and detailed instructions (in English). With the program can batch image watermarking problem
This article comes from: http://jk.scanmon.com/en/wp/2010/01/about_image_watermark.html
Have this problem on video in the Jacky on the message, ScanMom studio has also done technical support in this regard http://www.scanmon.com
Jacky for everyone to look at the picture I did add watermark

ImageMagick is a stable set of tools and development kits that can be used to read, write and deal with more than 89 kinds of basic format of the image files, including the popular TIFF, JPEG, GIF, PNG, PDF, and PhotoCD and other formats. The use of ImageMagick, you can web applications according to the needs of dynamically generated images, but also can be a picture or picture sequence to change the size, rotation, sharpening, subtractive or add special effects and results of operations in the same format or other format . The operation of the picture can be carried out through the command line, you can also use C / C + +, Perl, Java, PHP, Python, or Ruby programming to complete. ImageMagick also provides a high-quality 2D tool kit, in part to support SVG. Now, ImageMagic the main focus on performance, reduce the bug and providing a stable API and ABI on.
ImageMagick powerful, but it is free of charge.
ImageMagick functions
1. The pictures from one format to another format, including direct convert ico icon.
2. To change the size, rotation, Sharpen (sharpen), subtractive, picture effects
3. Thumbnails synthesis map (a montage of image thumbnails)
4. Suitable for the background of a transparent web images
5. Will be a group of pictures made gif animation, direct convert
6. Will be a few pictures made of a combination of image, montage
7. Write or draw a picture graph, with text shadows and border rendering.
8. To the Canadian border or frame pictures
9. Get some pictures of the characteristics of information
10, almost including the regular gimp plug-in functionality can be done. Even the rendering of various curve parameters. Just the wording of the command, complicated enough.
ImageMagick almost any non-proprietary operating system, compiler, both 32-bit or 64-bit CPU, including * nix, Windows ‘95 / ‘98 / ME / NT 4.0/2000/XP, Macintosh (MacOS 9 / 10 ), VMS, and OS / 2.
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