| 摘要 |
A video data stream is modified to encode at least four sets of metadata that respectively describe at least four video fields or frames preceding a current field or frame by modification of data defining the pixel values of that current field or frame. An encoder (e.g. watermark encoder) receives a current video image together with current metadata associated with the current image. A metadata delay also makes available to the decoder (e.g. watermark decoder) delayed metadata associated respectively with four or more of the preceding fields or frames. Then the encoder modifies pixel values (e.g. LSBs) of the current image not only to encode the current metadata but also the delayed metadata. At a decoder, if metadata for the current image is corrupted or missing, it can be recovered from one of the succeeding images. |
