Image processing apparatus and method, program code and storage medium
AssigneeCanon Kabushiki Kaisha
InventorJunichi Hayashi
Life of this patent
Estimating the term…
Abstract
An image processing apparatus which efficiently perform image coding and digital watermark embedding, and decoding and digital watermark extraction. For this purpose, an image is transformed to plural frequency subbands, at least one of the plural frequency subbands is selected, and in the selected frequency subband, a portion designated based on a matrix is changed, thereby digital watermark embedding is performed.
Claims42
An image processing apparatus comprising:
- transform means for transforming an image into plural frequency subbands;
- and
- digital watermark embedding means for selecting at least one frequency subband from said plural frequency subbands, and performing digital watermark embedding by changing a portion of the selected frequency subband designated based on a mask, by using a pattern array.
An image processing apparatus comprising:
- entropy decoding means for performing entropy decoding on a code string, obtained by performing digital watermark embedding by transforming an image into plural frequency subbands and changing a portion of at least one frequency subband designated based on a mask by using a pattern array, and performing entropy coding on all the frequency subbands including said frequency subband, and obtaining plural frequency subbands;
- and
- extraction means for selecting at least one frequency subband from said plural frequency subbands, and in the selected frequency subband, extracting a digital watermark by using the pattern array from the portion designated based on the mask.
An image processing apparatus comprising:
- transform means for transforming an image, obtained by performing digital watermark embedding by transforming an image into plural frequency subbands and changing a portion of at least one frequency subband designated based on a mask by using a pattern array, and performing inverse frequency transform on all the frequency subbands including said frequency subband, into plural frequency subbands;
- and
- extraction means for selecting at least one frequency subband from said plural frequency subbands, and in the selected frequency subband, extracting a digital watermark by using the pattern array from the portion designated based on the mask.
An image processing apparatus comprising extraction means for extracting a digital watermark from an image, obtained by transforming an image into plural frequency subbands, performing digital watermark embedding by peforming changing in at least one frequency subband by using a first pattern array, and performing inverse frequency transform on all the frequency subbands including said frequency subband, by using a second pattern array.
An image processing apparatus comprising:
- entropy decoding means for performing entropy decoding on a bit stream included in a code string, obtained by performing digital watermark embedding by transforming an image into plural frequency subbands and performing changing in at least one frequency subband by using a first pattern array, and performing entropy coding on all the frequency subbands including said frequency subband, and obtaining plural frequency subbands;
- image generation means for reproducing the image based on said plural frequency subbands;
- and
- extraction means for, in the image reproduced by said image generation means, performing digital watermark extraction by using a second pattern array.
An image processing apparatus comprising:
- inverse discrete wavelet transform means for performing inverse discrete wavelet transform on a pattern array;
- and
- digital watermark embedding means for performing digital watermark embedding by changing a portion of image data designated based on a mask by using the pattern array inverse discrete-wavelet transformed by said inverse discrete wavelet transform means.
An image processing method comprising:
- a transform step of transforming an image into plural frequency subbands;
- and
- a digital watermark embedding step of selecting at least one frequency subband from said plural frequency subbands, and performing digital watermark embedding by changing a portion of the selected frequency subband designated based on a mask, by using a pattern array.
An image processing method comprising:
- an entropy decoding step of performing entropy decoding on a code string, obtained by performing digital watermark embedding by transforming an image into plural frequency subbands and changing a portion of at least one frequency subband designated based on a mask by using a pattern array, and performing entropy coding on all the frequency subbands including said frequency subband, and obtaining plural frequency subbands;
- and
- an extraction step of selecting at least one frequency subband from said plural frequency subbands, and in the selected frequency subband, extracting a digital watermark by using a pattern array from the portion designated based on the mask.
An image processing method comprising:
- a transform step of transforming an image, obtained by performing digital watermark embedding by transforming an image into plural frequency subbands and changing a portion of at least one frequency subband designated based on a mask by using a pattern array, and performing inverse frequency transform on all the frequency subbands including said frequency subband, into plural frequency subbands;
- and
- an extraction step of selecting at least one frequency subband from said plural frequency subbands, and in the selected frequency subband, extracting a digital watermark by using the pattern array from the portion designated based on the mask.
An image processing method comprising an extraction step of extracting a digital watermark from an image, obtained by transforming an image into plural frequency subbands, performing digital watermark embedding by performing changing in at least one frequency subband by using a first pattern array, and performing inverse frequency transform on all the frequency subbands including said frequency subband, by using a second pattern array.
An image processing method comprising:
- an entropy decoding step of performing entropy decoding on a bit stream included in a code string, obtained by performing digital watermark embedding by transforming an image into plural frequency subbands and performing changing in at least one frequency subband by using a first pattern array, and performing entropy coding on all the frequency subbands including said frequency subband, and obtaining plural frequency subbands;
- an image generation step of reproducing the image based on said plural frequency subbands;
- and
- an extraction step of, in the image reproduced at said image generation step, performing digital watermark extraction by using a second pattern array.
Dependencies are inferred from the claim text.