Image processing apparatus

A method of embedding data in an image, said method comprising:

• forming said data to be embedded into a transform domain representation corresponding to a spatial domain form of said data, said transform domain representation providing a plurality of sub-bands divided by spatial frequency components, said transform domain representation being the discrete wavelet transform, each of said sub-bands comprising wavelet coefficients;
• and
• combining said data with said image by generating a transform domain form of said image, combining said data with said image in the transform domain, and generating a spatial domain representation of said combined image and data, wherein said forming said data into the transform domain representation comprises:
• forming said data into said sub-bands in a scan direction, with an effect that said data is embedded in only a first low vertical, high horizontal spatial frequencies sub-band of the discrete wavelet transform, and only a second high vertical, low horizontal spatial frequencies sub-band of the discrete wavelet transform, said data being embedded into to said first and second sub-bands in a vertical scan direction and a horizontal scan direction respectively, symbols of said data being added to the wavelet coefficients, said scan direction being in the same direction in the sub-band as the direction of the low spatial frequencies of the image.

An apparatus for embedding data in an image, said apparatus comprising:

• means for forming said data to be embedded into a transform domain representation corresponding to a spatial domain form of said data, said transform domain representation providing a plurality of sub-bands divided by spatial frequency components, said transform domain representation being the discrete wavelet transform, each of said sub-bands comprising wavelet coefficients;
• means for combining said data with said image by generating a transform domain form of said image, combining said data with said image in the transform domain, and generating a spatial domain representation of said combined image and data, wherein means for forming said data into the transform domain representation comprises:
• means for forming said data into said sub-bands in a scan direction, with an effect that said data is embedded in only a first low vertical, high horizontal spatial frequencies sub-band of the discrete wavelet transform, and only a second high vertical, low horizontal spatial frequencies sub-band of the discrete wavelet transform, said data being embedded into said first and second sub-bands in a vertical scan direction and a horizontal scan direction respectively, symbols of said data being added to the wavelet coefficients, said scan direction being in the same direction in the sub-band as the direction of the low spatial frequencies of the image.

An image processing apparatus operable to embed data into an image, said apparatus comprising:

• a combining processor operable to form said data into a transform domain representation providing a plurality of sub-bands divided by spatial frequency components, said transform domain representation being the discrete wavelet transform, each of said sub-bands comprising wavelet coefficients and, in combination with a transform processor, to combine said data with said image in a spatial domain form of said image, said transform processor generating a spatial domain representation of said transform domain representation of said data, said data being combined with said image by said combining processor in said spatial domain, wherein said data is formed into said sub-bands representing said data in a scan direction, with an effect that said data is embedded in only a first low vertical, high horizontal spatial frequencies sub-band of the discrete wavelet transform, and only a second high vertical, low horizontal spatial frequencies sub-band of the discrete wavelet transform, said data being embedded into to said first and second sub-bands in a vertical scan direction and a horizontal scan direction respectively, symbols of said data being added to the wavelet coefficients, said scan direction being in the same direction in the sub-band as the direction of the low spatial frequencies of the image.

A method of embedding data in an image, said method comprising:

• forming said data to be embedded into a transform domain representation corresponding to a spatial domain form of said data, said transform domain representation providing a plurality of sub-bands divided by spatial frequency components, said transform domain representation being the discrete wavelet transform, each of said sub-bands comprising wavelet coefficients;
• and
• combining said data with said image by generating a spatial domain representation of said transform domain representation of said data, and combining said data with said image in said spatial domain, wherein said forming said data into the transform domain representation comprises:
• forming said data into said sub-bands in a scan direction, with an effect that said data is embedded in only a first low vertical, high horizontal spatial frequencies sub-band of the discrete wavelet transform, and only a second high vertical, low horizontal spatial frequencies sub-band of the discrete wavelet transform, said data being embedded into to said first and second sub-bands in a vertical scan direction and a horizontal scan direction respectively, symbols of said data being added to the wavelet coefficients, said scan direction being in the same direction in the sub-band as the direction of the low spatial frequencies of the image.

An apparatus for embedding data in an image, said apparatus comprising:

• means for forming said data to be embedded into a transform domain representation corresponding to a spatial domain form of said data, said transform domain representation providing a plurality of sub-bands divided by spatial frequency components, said transform domain representation being the discrete wavelet transform, each of said sub-bands comprising wavelet coefficients;
• means for combining said data with said image by generating a spatial domain representation of said transform domain representation of said data, and combining said data with said image in said spatial domain, wherein means for forming said data into the transform domain representation comprises:
• means for forming said data into said sub-bands in a scan direction, with an effect that said data is embedded in only a first low vertical, high horizontal spatial frequencies sub-band of the discrete wavelet transform, and only a second high vertical, low horizontal spatial frequencies sub-band of the discrete wavelet transform, said data being embedded into said first and second sub-bands in a vertical scan direction and a horizontal scan direction respectively, symbols of said data being added to the wavelet coefficients, said scan direction being in the same direction in the sub-band as the direction of the low spatial frequencies of the image.