Abstract: In at least one embodiment of the present invention, quality of image is improved by sufficiently sharpening the image through an appropriate high-frequency compensation with a simple arrangement, not only for still images but also for moving images and even if the images have already undergone image enlarging processes. In at least one embodiment, an HPF extracts high-frequency components from an input image signal. A square operator generates a squared signal by squaring the first signal. A first differentiator generates a first differentiation signal by differentiating the squared signal. The second differentiator generates a second differentiation signal by differentiating the input image signal. A multiplier generates a second signal by multiplying the first differentiation signal by the second differentiation signal. An adder generates an output image signal by adding the second signal to the input image signal, as a compensation signal.

Abstract: In at least one embodiment of the present invention, quality of image is improved by sufficiently sharpening the image through an appropriate high-frequency compensation with a simple arrangement, not only for still images but also for moving images and even if the images have already undergone image enlarging processes. In at least one embodiment, an HPF extracts high-frequency components from an input image signal. A square operator generates a squared signal by squaring the first signal. A first differentiator generates a first differentiation signal by differentiating the squared signal. The second differentiator generates a second differentiation signal by differentiating the input image signal. A multiplier generates a second signal by multiplying the first differentiation signal by the second differentiation signal. An adder generates an output image signal by adding the second signal to the input image signal, as a compensation signal.

Abstract: 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.

Abstract: 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.

Abstract: A system for distributing broadcast contents, in which the copyright of the broadcast contents can be protected, is provided. The system is a watermarking application system for broadcast contents copyright protection, constituted by a broadcasting station of broadcast contents, a broadcasting receiver of the broadcast contents, a network monitoring agent for monitoring secondary contents of the broadcast contents, a secondary content player for playing secondary contents, communication receivers for recognizing distribution of secondary contents, etc. Pieces of digital watermarking embedding equipment are provided in the broadcasting station and the broadcasting receiver respectively. Pieces of digital watermarking extraction equipment are provided in the network monitoring agent and the secondary content player. Particularly, the broadcast contents are outputted through an analog output or an internal disk.