Abstract: Even in the case where a positional misalignment occurs to an embedded digital watermark, watermark information is accurately detected. A digital watermark embedding device includes a block dividing section for dividing digital data into a plurality of blocks each having a predetermined size, and a block selecting section for selecting m blocks (m is an integer no less than 2) from the plurality of the blocks in accordance with a predetermined order. The device further includes an additional pattern setting section for setting a combination of m additional patterns which are selected from a plurality types of additional patterns, the combination corresponding to one data element to be embedded into the selected m blocks, and an additional pattern embedding section for embedding each of the set additional patterns into each of the selected blocks.

Abstract: Information embedding is performed by extracting vertices constituting a polygon from vector data, and changing a number of points that exist on sides of the polygon based on embedment information. Further, information reading is performed by extracting points existing on the sides of the polygon from the embedment information and embedded vector data, and by reading the embedment information according to a predetermined rule.

Abstract: An information-detecting apparatus (1) including a receiving unit (3) operable to receive digital data (2) that includes several pieces of element data, in which a change amount is imparted to a value of each of first and second element data among the several pieces of element data, a first selecting unit (4) operable to select, as target data (6), a data set that includes the first and second element data, a second selecting unit (5) operable to select, as neighboring data (7), element data in proximity to each of the first and second element data, a calculating unit (8) operable to calculate, based on both of the target data (6) and the neighboring data (7), the change amount imparted to each of the first and second element data, and a detecting unit (10) operable to detect the additional information in accordance with the change amount.

Abstract: A bit stream is decoded to generate first quantized DCT-coefficients. The first quantized DCT-coefficients are inversely quantized using a first quantization table, thereby generating DCT-coefficients. The resulting DCT-coefficients are quantized using a second quantization table, thereby generating second quantized DCT-coefficients. Elements in the second quantization table are smaller in value than those in the first quantization table. Predetermined additional information is embedded into the second quantized DCT-coefficients. The second quantized DCT-coefficients having the additional information embedded therein are encoded to produce a bit stream having the additional information embedded therein. The second quantization table is set to be smaller in value than the first quantization table.

Abstract: An information-detecting apparatus (1) including a receiving unit (3) operable to receive digital data (2) that includes several pieces of element data, in which a change amount is imparted to a value of each of first and second element data among the several pieces of element data, a first selecting unit (4) operable to select, as target data (6), a data set that includes the first and second element data, a second selecting unit (5) operable to select, as neighboring data (7), element data in proximity to each of the first and second element data, a calculating unit (8) operable to calculate, based on both of the target data (6) and the neighboring data (7), the change amount imparted to each of the first and second element data, and a detecting unit (10) operable to detect the additional information in accordance with the change amount.

Abstract: Even in the case where a positional misalignment occurs to an embedded digital watermark, accurate detection of watermark information is provided. A digital watermark embedding device includes: a block dividing section (101) for dividing digital data into a plurality of blocks each having a predetermined size; a block selecting section (102) for selecting m blocks (m is an integer no less than 2) from the plurality of the blocks in accordance with a predetermined order; an additional pattern setting section (103) for setting a combination of m additional patterns which are selected from a plurality types of additional patterns, the combination corresponding to one data element to be embedded into the selected m blocks; and an additional pattern embedding section (104) for embedding each of the set additional patterns into each of the selected blocks.

Abstract: A digital image signal is divided into blocks. Each of the divided blocks is subjected to orthogonal transformation. As a result, the divided blocks are transformed into several frequency components. One or more frequency components are selected in accordance with a characteristic amount that is extracted from the several frequency components. Values of the selected frequency components are operated under a predetermined rule in accordance with an embedment signal that is generated from embedment information.

Abstract: A characteristic amount is retained and calculated from an entered video signal. Embedment intensity is retained and calculated from the retained characteristic amount. Embedment information is embedded as digital watermarks into the entered video signal in accordance with the retained embedment intensity of the previous frame or field that is located at a position earlier in time than a target image subject to digital watermark embedment. As a result, an output signal of video having the digital watermarks embedded therein is produced. The digital watermarks are embedded into the target image with reference to another image located at a position earlier in time than the target image. Such digital watermark embedment suppresses a delay in output of an output image with reference to an input image.

Abstract: Information embedding is performed by extracting vertices composing a polygon from vector data, and changing the number of points that exist on the sides of the polygon based on the embedment information. Information reading is performed by extracting points existing on the sides of the polygon from the embedment information embedded vector data, and reading the embedment information according to the predetermined rule.

Abstract: An input image is divided into local regions, each of which is formed by a macro block. An embedment intensity is determined for each of the local regions by using a calculated characteristic amount and a compression bit rate. Digital watermarks are embedded at the determined embedment intensity into the input image at each of the local regions thereof. The input image is encoded, thereby providing a compressed bit stream that has the digital watermarks embedded therein.

Abstract: A reproduction equipment converts an identification code of the reproduction equipment into a plurality of signal sequences using a correspondence table and embeds the obtained plurality of signal sequences in AV signals as a digital watermark. A reproduction equipment specifying equipment compares correlation values of the AV signals, containing the digital watermark embedded therein with all signal sequences contained in a correspondence table. A comparison of the correlation values with a previously set threshold value determines the embedded signal sequences and the identification code of the reproduction equipment which may be extracted.

Abstract: A bit stream is decoded to generate first quantized DCT-coefficients. The first quantized DCT-coefficients are inversely quantized using a first quantization table, thereby generating DCT-coefficients. The resulting DCT-coefficients are quantized using a second quantization table, thereby generating second quantized DCT-coefficients. Elements in the second quantization table are smaller in value than those in the first quantization table. Predetermined additional information is embedded into the second quantized DCT-coefficients. The second quantized DCT-coefficients having the additional information embedded therein are encoded to produce a bit stream having the additional information embedded therein. The second quantization table is set to be smaller in value than the first quantization table.

Abstract: An inherent information-generating unit is operable to generate inherent information inherent to each frame image that forms part of moving image data. An information-embedding unit is operable to embed inherent information on a specific frame image as tampering-detecting information into a different frame image in which the inherent information is to be embedded. The specific frame image is temporally separated in position from the different frame image.

Abstract: A digital image signal is divided into blocks. Each of the divided blocks is subjected to orthogonal transformation. As a result, the divided blocks are transformed into several frequency components. One or more frequency components are selected in accordance with a characteristic amount that is extracted from the several frequency components. Values of the selected frequency components are operated under a predetermined rule in accordance with an embedment signal that is generated from embedment information.

Abstract: A characteristic amount is retained and calculated from an entered video signal. Embedment intensity is retained and calculated from the retained characteristic amount. Embedment information is embedded as digital watermarks into the entered video signal in accordance with the retained embedment intensity of the previous frame or field that is located at a position earlier in time than a target image subject to digital watermark embedment. As a result, an output signal of video having the digital watermarks embedded therein is produced. The digital watermarks are embedded into the target image with reference to another image located at a position earlier in time than the target image. Such digital watermark embedment suppresses a delay in output of an output image with reference to an input image.

Abstract: An input image is divided into local regions, each of which is formed by a macro block. Embedment intensity is determined for each of the local regions using a calculated characteristic amount and a compression bit rate. Digital watermarks are embedded at the determined embedment intensity into the input image at each of the local regions thereof. The input image is encoded, thereby providing a compressed bit stream that has the digital watermarks embedded therein.

Abstract: Picture quality loss is minimized and buffer underflow and overflow are prevented when extracting and recombining a plurality of consecutive scenes from an MPEG stream. The smallest number of pictures (equivalent at most to 1 second) that must be re-encoded so that the scene can be independently reproduced is detected to identify the re-encoding target picture. Then the picture type (I, P, B) after the pictures are re-encoded is determined. Buffer fullness is calculated, and the code allocation to the re-encoding range is calculated from buffer fullness and target picture count. The code allocation to each target picture is then calculated, and the target pictures are re-encoded and connected.

Abstract: A reproduction equipment converts an identification code of the reproduction equipment into a plurality of signal sequences using a correspondence table and embeds the obtained plurality of signal sequences in AV signals as a digital watermark. A reproduction equipment specifying equipment compares correlation values of the AV signals, containing the digital watermark embedded therein with all signal sequences contained in a correspondence table. A comparison of the correlation values with a previously set threshold value determines the embedded signal sequences and the identification code of the reproduction equipment which may be extracted.