Electronic apparatus for embedding and extracting watermark and controlling method thereof

A controlling method of an electronic apparatus, the method comprising:

• obtaining information on sizes of frequency components for a plurality of color channels constituting an image;
• identifying a color channel, from among the plurality of color channels, having a size ratio of a high frequency component that is highest among the plurality of color channels;
• based on a size of the high frequency component of the identified color channel for each of a plurality of areas constituting the image, identifying an embedding strength of a watermark for each of the plurality of areas;
• embedding, into the watermark, (i) information corresponding to the embedding strength for each of the plurality of areas and (ii) locations of each of the plurality of areas into the watermark;
• and
• embedding, into the image, the watermark in which the information corresponding to the embedding strength for each of the plurality of areas and the locations of each of the plurality of areas are embedded.

A non-transitory computer readable medium having instructions stored therein, which when executed by a processor of an electronic apparatus, cause the processor to execute a method comprising:

• obtaining information on sizes of frequency components for a plurality of color channels constituting an image;
• identifying a color channel, from among the plurality of color channels, having a size ratio of a high frequency component that is highest among the plurality of color channels;
• based on a size of the high frequency component of the identified color channel for each of a plurality of areas constituting the image, identifying an embedding strength of a watermark for each of the plurality of areas;
• embedding, into the watermark, (i) information corresponding to the embedding strength for each of the plurality of areas and (ii) locations of each of the plurality of areas into the watermark;
• and
• embedding, into the image, the watermark in which the information corresponding to the embedding strength for each of the plurality of areas and the locations of each of the plurality of areas are embedded.