利索-全球专利检索

  1. 登录
  2. 注册

搜索结果

267 条记录 (耗时 0.028 秒)

    Method and apparatus for watermarking video images
    34.
    发明授权
    Method and apparatus for watermarking video images 有权
    用于对视频图像进行水印的方法和装置

    公开(公告)号：US06798894B2

    公开(公告)日：2004-09-28

    申请号：US09778307

    申请日：2001-02-06

    申请人： Geoffrey B. Rhoads

    发明人： Geoffrey B. Rhoads

    IPC分类号： H04K100

    CPC分类号： G06T1/0035 ,  G06K9/00442 ,  G06T1/0064 ,  G06T2201/0051 ,  G06T2201/0052 ,  G06T2201/0053 ,  G06T2201/0061 ,  G10L19/018 ,  G11B20/00884 ,  G11B2020/10537 ,  H04N1/00005 ,  H04N1/00037 ,  H04N1/00079 ,  H04N1/32122 ,  H04N1/32154 ,  H04N1/32165 ,  H04N1/32187 ,  H04N1/32277 ,  H04N1/32352 ,  H04N5/913 ,  H04N19/467 ,  H04N19/48 ,  H04N19/60 ,  H04N19/61 ,  H04N21/23892 ,  H04N21/8358 ,  H04N2005/91335 ,  H04N2201/3205 ,  H04N2201/3207 ,  H04N2201/3233 ,  H04N2201/327

    摘要： Embedding a watermark in an image by changing selected DCT coefficients in the blocks and macro blocks of coefficients which represent the image. The changes in the blocks that comprise each macro block are done in a coordinated manner so that the phase of the watermark signal is preserved across the block boundaries. By preserving the phase across block boundaries, a detectable grid is formed which can be used as an orientation and scaling grid. Furthermore, by preserving the phase across block boundaries the visual artifacts introduced by the watermark are minimized. The bit rate of the image signal is preserved by maintaining a count (referred to as the cumulative change count) that represents the amount that the bit rate has been increased by changes in coefficients less the amount that the bit rate has been decreased by changes in the coefficients. If at any time the cumulative change count exceeds a pre-established limit, coefficient changes that decrease the cumulative change count continue; however, coefficient changes that increase the cumulative change count are suspended. The suspension of coefficient changes that increase the cumulative change count continues until the cumulative change count falls below the pre-established limit.

    摘要翻译： 通过改变代表图像的系数块和宏块中的所选DCT系数，在图像中嵌入水印。 构成每个宏块的块中的改变以协调的方式完成，使得水印信号的相位跨越块边界被保留。 通过跨块边界保持相位，形成可检测的网格，可以将其用作取向和缩放网格。 此外，通过在块边界之间保持相位，水印引入的视觉伪像被最小化。 图像信号的比特率通过维持计数（称为累积改变计数）来保持，该计数表示通过系数的变化而减小比特率已经被减少的量的比特率的量 系数。 如果在任何时候累积变化计数超过预先确定的限制，则减少累积变化计数的系数变化继续; 然而，暂停增加累积变化计数的系数变化。 增加累积变化计数的系数变化的暂停继续，直到累积变化计数低于预先确定的限制。

    Forensic communication apparatus and method
    36.
    发明申请
    Forensic communication apparatus and method 失效
    取证通信装置及方法

    公开(公告)号：US20040125208A1

    公开(公告)日：2004-07-01

    申请号：US10674910

    申请日：2003-09-29

    发明人： Michael F. Malone ,  Frederick J. Murphy

    IPC分类号： H04N005/225

    CPC分类号： G06T1/005 ,  H04L9/0643 ,  H04L9/08 ,  H04L9/302 ,  H04L9/3218 ,  H04L9/3221 ,  H04L9/3239 ,  H04L9/3249 ,  H04L9/3263 ,  H04L9/3271 ,  H04L63/045 ,  H04L2209/60 ,  H04L2209/608 ,  H04L2209/80 ,  H04N1/32101 ,  H04N1/32272 ,  H04N1/32277 ,  H04N2201/0084 ,  H04N2201/3205 ,  H04N2201/3214 ,  H04N2201/3215 ,  H04N2201/3233 ,  H04N2201/3235 ,  H04N2201/3253 ,  H04N2201/3274 ,  H04N2201/3281 ,  H04N2201/3283

    摘要： Forensic communication apparatus and method. An apparatus is disclosed for recording image or other data in real time. The apparatus includes a capture device for capturing the image or other information. Once captured, a local verification device is operable to indelibly mark the captured image or other information with the date, time, location and information identifying the creator of the data. A transmitter is provided for transmitting the locally verified captured image or other information in real time to a secure storage facility. The capture device is operable, after the locally verified captured image or other information is transmitted to the secure storage facility, to receive and verify acknowledgment of the receipt of the transmitted locally verified captured image or other information to the storage facility.

    摘要翻译： 取证通信装置及方法。 公开了用于实时记录图像或其他数据的装置。 该装置包括用于捕获图像或其他信息的捕获装置。 一旦被捕获，本地验证设备可操作地用识别数据的创建者的日期，时间，位置和信息来不可错地地标记所捕获的图像或其他信息。 提供发射机用于将本地验证的捕获图像或其他信息实时地发送到安全存储设施。 在将本地验证的捕获图像或其他信息发送到安全存储设施之后，捕获设备可操作以接收并验证所接收到的已发送的本地验证的捕获图像或其他信息到存储设施的确认。

    Method for authentication of JPEG image data
    37.
    发明申请
    Method for authentication of JPEG image data 失效

    公开(公告)号：US20040013268A1

    公开(公告)日：2004-01-22

    申请号：US10200819

    申请日：2002-07-22

    申请人： Xerox Corporation

    发明人： Ricardo L. de Queiroz

    IPC分类号： H04N007/167

    CPC分类号： H04N1/32144 ,  G06T9/007 ,  H04N1/32272 ,  H04N1/32277 ,  H04N1/32283 ,  H04N2201/3235

    摘要： What has been disclosed is a method for authentication of JPEG image data prior to transmission to an intended recipient which enables the recipient to ascertain whether the received image file originated from a known identified source or whether the contents of the file have been altered in some fashion prior to receipt. In accordance to the present invention, to encode verification information a unique hashing function is derived from a first section of image data contained in the JPEG compressed image in such a way that any changes subsequently made to said first section of image data would be reflected in a different hashing function being derived therefrom. An integrity checking number is produced from the first section's derived hashing function. The integrity checking number is subsequently encrypted into a signature string. The signature string is then embedded into a next section of the image data. The process is repeated until all sections of image data have been processed. The signature string corresponding to the very last section of data is self-embedded therein. As the embedding of a previous section's integrity checking number is done without modifying the JPEG bit stream any JPEG decoder found in the arts can thereafter properly decode the image. The image file is then transmitted to an intended recipient. To decode the embedded verification information upon receipt of the JPEG image file by the recipient a hashing function is computed by the recipient from a first section of image data contained in the received image file. A second section of data is identified wherein the signature string for the first section of data had been embedded. The signature is then decoded from the data. The signature string is thereafter decrypted to yield the hashing function (integrity checking) number contained therein. The two numbers are then compared against each other. If the first checking number matches the number contained in retrieved signature string which had been previously embedded therein by the author then it can be ascertained that the image data for that first section is authentic. The process is repeated for each successive section of data until all the data sections of the image file have been processed.

    Method and apparatus for watermarking images
    38.
    发明申请
    Method and apparatus for watermarking images 失效
    水印图像的方法和装置

    公开(公告)号：US20030147547A1

    公开(公告)日：2003-08-07

    申请号：US10220776

    申请日：2003-02-11

    发明人： Ching-Yung Lin ,  Shih-Fu Chang

    IPC分类号： G06K009/00

    CPC分类号： G06T1/0057 ,  G06T1/0042 ,  G06T1/005 ,  G06T2201/0052 ,  G06T2201/0061 ,  H04N1/32165 ,  H04N1/32187 ,  H04N1/32277 ,  H04N1/3232 ,  H04N2201/3236 ,  H04N2201/327

    摘要： Digital watermarks are embedded in image data (102)in order to enable authentication of the image data and/or replacement of rejected portions of the image data. Authentication codes are derived by comparing selected discrete cosine transform (DCT) (104) coefficients within DCT data (106) derived from the original, spatial-domain image data. The authentication codes thus generated are embedded in DCT coefficients (612) other than the ones which were used to derive the authentication codes. The resulting, watermarked data can be sent or made available to one or more recipients who can compress or otherwise use the watermarked data. Image data derived from the watermarked datanulle.g, compressed versions of the watermarked datanullcan be authenticated by: extracting the embedded authentication codes, comparing DCT coefficients derived from the coefficients from which the original authentication codes were generated; and determining whether the compared DCT coefficients are consistent with the extracted authentication codes.

    摘要翻译： 数字水印被嵌入在图像数据（102）中，以便能够对图像数据进行认证和/或替换图像数据的被拒绝的部分。 通过比较从原始的空间域图像数据导出的DCT数据（106）内的选定的离散余弦变换（DCT）（104）系数，导出认证码。 这样生成的认证码被嵌入除了用于导出认证码的那些之外的DCT系数（612）中。 所得到的水印数据可以被发送或使其可用于可压缩或以其他方式使用水印数据的一个或多个接收者。 从水印数据导出的图像数据（例如，水印数据的压缩版本）可以通过以下方式来认证：提取嵌入的认证码，比较从产生原始认证码的系数导出的DCT系数; 以及确定所述比较的DCT系数是否与所提取的认证码一致。

    Processing a compressed media signal
    39.
    发明申请
    Processing a compressed media signal 审中-公开
    处理压缩媒体信号

    公开(公告)号：US20030016756A1

    公开(公告)日：2003-01-23

    申请号：US10196120

    申请日：2002-07-16

    发明人： Frits Anthony Steenhof ,  Gerrit Cornelis Langelaar

    IPC分类号： H04N007/12

    CPC分类号： H04N19/467 ,  G06T1/0035 ,  G06T2201/0052 ,  G06T2201/0053 ,  H04N1/32154 ,  H04N1/32277

    摘要： A method and arrangement are disclosed for processing a compressed media signal, for example, embedding a watermark in an MPEG2 video signal. The watermark, a spatial noise pattern (140), is embedded (123) by selectively discarding the smallest quantized DCT coefficients. The discarded coefficients are subsequently merged in the runs of other run/level pairs. To compensate for a too large reduction of the bit rate, some of the new run/level pairs are not variable-length encoded (124) but represented by longer code words according to further coding rule (125) providing such longer code words, for example, MPEG's nullEscape codingnull.

    摘要翻译： 公开了一种用于处理压缩媒体信号的方法和装置，例如，将水印嵌入在MPEG2视频信号中。 通过选择性地丢弃最小的量化DCT系数来嵌入（123）水印，空间噪声模式（140）。 丢弃的系数随后在其他运行/电平对的运行中合并。 为了补偿比特率的太大的降低，一些新的运行/电平对不是可变长度编码的（124），而是根据提供这种较长代码字的进一步的编码规则（125）由更长的代码字表示，用于 例如，MPEG的“Escape编码”。