Identification of watermarked content
There are provided methods and systems for identifying watermarked content. In one implementation, such a method includes receiving content including a digital watermark, and detecting the digital watermark, the detecting being performed without use of a decoder configured to read the digital watermark. In implementations in which the content includes an audio watermark, detecting the audio watermark includes filtering an audio frequency spectrum of the content, sampling the audio frequency spectrum to generate data corresponding to the content, determining a first audio level for searching the data based on the sampling, and searching the data at the first audio level. The content may be identified as watermarked content including an audio watermark when multiple, single frequency tones are detected.
1. A method comprising:
receiving a content including an audio watermark encoded in the content;
detecting that the audio watermark exists in the content;
wherein the detecting of the audio watermark encoded in the content is performed without decoding the audio watermark encoded in the content, and includes:
filtering an audio frequency spectrum of the content;
sampling the audio frequency spectrum to generate data corresponding to the content;
determining a first audio level for searching the data based on the sampling;
searching the data at the first audio level for a plurality of single frequency tones; and
identifying the content as watermarked content when the plurality of single frequency tones are detected by the searching.
2. The method of claim 1 , wherein detecting the audio watermark further comprises:
generating data corresponding to the content including the audio watermark; and
searching the data to detect the audio watermark.
3. The method of claim 1 , wherein the content comprises audio-visual content.
4. The method of claim 3 , wherein the audio-visual content is scheduled for use in a transmission stream, the method enabling identification of the content as watermarked content in real-time with respect to the transmission stream.
5. The method of claim 1 , wherein detecting the audio watermark further comprises repeating the searching at successively lower audio levels until the plurality of single frequency tones are detected at an audio level above a lower bound audio level for the searching.
6. A system comprising:
a system processor and a system memory;
a watermark detection engine stored in the system memory, the watermark detection engine, under control of the system processor, configured to:
receive a content including an audio watermark encoded in the content;
detect that the audio watermark exists in the content;
wherein detection of the audio watermark encoded in the content is performed without decoding the audio watermark encoded in the content, and includes:
filtering an audio frequency spectrum of the content;
sampling the audio frequency spectrum to generate data corresponding to the content;
determining a first audio level for searching the data based on the sampling;
searching the data at the first audio level for a plurality of single frequency tones; and
identifying the content as watermarked content when the plurality of single frequency tones are detected by the searching.
7. The system of claim 6 , wherein the watermark detection engine is further configured to:
generate data corresponding to the content including the audio watermark; and
search the data to detect the audio watermark.
8. The system of claim 6 , wherein the content comprises audio-visual content.
9. The system of claim 8 , wherein the audio-visual content is scheduled for use in a transmission stream, the watermark detection engine configured to identify the content as watermarked content in real-time with respect to the transmission stream.
10. The system of claim 6 , wherein the watermark detection engine is further configured to repeat the searching at successively lower audio levels until the plurality of single frequency tones are detected at an audio level above a lower bound audio level for the searching.
11. A computer-readable medium having stored thereon instructions which, when executed by a processor, instantiate a watermark detection engine configured to:
receive a content including an audio watermark encoded in the content;
detect that the audio watermark exists in the content;
wherein detection of the audio watermark encoded in the content is performed without decoding the audio watermark encoded in the content, and includes:
filtering an audio frequency spectrum of the content;
sampling the audio frequency spectrum to generate data corresponding to the content;
determining a first audio level for searching the data based on the sampling;
searching the data at the first audio level for a plurality of single frequency tones; and
identifying the content as watermarked content when the plurality of single frequency tones are detected by the searching.
12. The computer-readable medium of claim 11 , wherein the content comprises audio-visual content.
13. The computer-readable medium of claim 12 , wherein the audio-visual content is scheduled for use in a transmission stream, the watermark detection engine configured to identify the content as watermarked content in real-time with respect to the transmission stream.
14. The computer-readable medium of claim 11 , wherein the watermark detection engine is further configured to repeat the searching at successively lower audio levels until the plurality of single frequency tones are detected at an audio level above a lower bound audio level for the searching.