摘要:
A digital watermark embedding device according to the present invention includes: a watermark pattern generation part (4) which generates a watermark pattern varying in a time direction based on embedding information to be embedded in an input image to be processed; a synchronization pattern generation part (3) which outputs a fixed pattern for detecting synchronization as a watermark pattern; a pattern switching part (5) which selects between the watermark pattern output by the synchronization pattern generation part (3) and the watermark pattern output by the watermark pattern generation part (4) based on the input image (7a); and an embedding processing part (6) which adds the selected watermark pattern to each pixel value of the input image (7a) to generate an embedded image (7c) having a digital watermark embedded therein. Consequently, phase shifting may be detected based on the fixed pattern for detecting synchronization, there by being capable of precisely detecting the digital watermark out of a recaptured image as well.
摘要:
An electronic image into which an electronic watermark is to be embedded is divided into a plurality of image regions spatially, and pixels each having a property of being difficult to visually recognize a variation in a pixel value are extracted as adaptive pixels from each of the plurality of image regions. A variation between the pixel values of the adaptive pixels in one of the plurality of image regions and those of the adaptive pixels in an adjacent one of the plurality of image regions is produced, and the pixel values of the adaptive pixels of the plurality of image regions are varied in a time direction according to the value of an embedded bit set of the electronic watermark. An electronic-watermark-embedded image is then generated by making the variation in the pixel values of the adaptive pixels vary step by step at a boundary between the two of the plurality of image regions and/or in the time direction so that the variation makes a slow transition.
摘要:
A digital watermark embedding device according to the present invention includes: a watermark pattern generation part (4) which generates a watermark pattern varying in a time direction based on embedding information to be embedded in an input image to be processed; a synchronization pattern generation part (3) which outputs a fixed pattern for detecting synchronization as a watermark pattern; a pattern switching part (5) which selects between the watermark pattern output by the synchronization pattern generation part (3) and the watermark pattern output by the watermark pattern generation part (4) based on the input image (7a); and an embedding processing part (6) which adds the selected watermark pattern to each pixel value of the input image (7a) to generate an embedded image (7c) having a digital watermark embedded therein. Consequently, phase shifting may be detected based on the fixed pattern for detecting synchronization, there by being capable of precisely detecting the digital watermark out of a recaptured image as well.
摘要:
An electronic image into which an electronic watermark is to be embedded is divided into a plurality of image regions spatially, and pixels each having a property of being difficult to visually recognize a variation in a pixel value are extracted as adaptive pixels from each of the plurality of image regions. A variation between the pixel values of the adaptive pixels in one of the plurality of image regions and those of the adaptive pixels in an adjacent one of the plurality of image regions is produced, and the pixel values of the adaptive pixels of the plurality of image regions are varied in a time direction according to the value of an embedded bit set of the electronic watermark. An electronic-watermark-embedded image is then generated by making the variation in the pixel values of the adaptive pixels vary step by step at a boundary between the two of the plurality of image regions and/or in the time direction so that the variation makes a slow transition.