초록 ▼

The implementations of digital watermarks can be optimally suited to particular transmission, distribution and storage mediums given the nature of digitally-sampled audio, video and other multimedia works. Watermark application parameters can be adapted to the individual characteristics of a given d

The implementations of digital watermarks can be optimally suited to particular transmission, distribution and storage mediums given the nature of digitally-sampled audio, video and other multimedia works. Watermark application parameters can be adapted to the individual characteristics of a given digital sample stream. Watermark information can be either carried in individual samples or in relationships between multiple samples, such as in a waveform shape. More optimal models may be obtained to design watermark systems that are tamper-resistant given the number and breadth of existent digitized sample options with different frequency and time components. The highest quality of a given content signal may be maintained as it is mastered, with the watermark suitably hidden, taking into account usage of digital filters and error correction. The quality of the underlying content signals can be used to identify and highlight advantageous locations for the insertion of digital watermarks. The watermark is integrated as closely as possible to the content signal, at a maximum level to force degradation of the content signal when attempts are made to remove the watermarks.

대표청구항 ▼

[ What is claimed is:] [1.] A method for amplitude independent encoding of digital watermark information in a signal, comprising steps of:determining in said signal a sample window having a minimum and a maximum;determining a quantization interval of said sample window, where said quantitization int

[ What is claimed is:] [1.] A method for amplitude independent encoding of digital watermark information in a signal, comprising steps of:determining in said signal a sample window having a minimum and a maximum;determining a quantization interval of said sample window, where said quantitization interval can be used to quantize normalized window samples;normalizing the sample window to provide normalized samples, where normalized samples conform to a limited range of values, proportional to real sample values, and comprise a representation of the real sample values with a resolution higher than the real range of values, and where the normalized values can be divided by the quantization interval into distinct quantization levels;analyzing the normalized samples to determine quantization levels;comparing the message bits to the corresponding quantization level information from the analyzing step;when a bit conflicts with the quantization level, adjusting the quantization level of said sample window to correspond to the message bit; andde-normalizing the analyzed normalized samples.