With the rapid development of multimedia and network technologies,
the image became an important source of obtaining information and it was a hot
research topic how to retrieve the wanted information from many pictures. In
order to effectively retrieve the image information, the image retrieval system
based on digital watermarking technology was designed and implemented. Two commonly
used image retrieval methods were introduced, including text-based image retrieval
and content-based image retrieval and their advantages and disadvantages were
analyzed. The characteristics, basic principles and typical algorithms of digital
watermark were briefly discussed. On the basis of them, the watermarking algorithms
based on discrete cosine transform were focused on. The processes of watermark
embedding, extracting were emphatically analyzed and their processes were given.
The image matching was implemented to retrieve the desired image based on normalized
cross correlation method. The experimental simulation results showed that the
watermark had good invisibility and the system quickly realized watermark embedding,
extracting and matching which had certain theoretical and practical values.