Signal encoding to reduce perceptibility of changes over time
The present disclosures relates generally to digital watermarking and data hiding. One claim recites a smartphone comprising: a camera to capture video of a display that is rendering video, in which the video comprises a first watermark signal embedded in a first portion of the data, a second watermark signal embedded in a second portion of the data, and a third watermark signal embedded in a third portion of the data, in which at least two of the first watermark signal, second watermark signal and third watermark signal are inversely related to one another; electronic memory for buffering data representing captured video; one or more electronic processors programmed for: applying a first perspective distortion to the data representing the captured video to yield first perspective distorted video; and analyzing the first perspective distorted video to detect digital watermarking, in which a second perspective distortion is applied to the data representing the captured video to yield second perspective distorted video when the analyzing does not detect digital watermarking, and then performing analyzing the second perspective distorted video to detect digital watermarking. Of course, other claims are provided too.
1. A method comprising:
obtaining data representing video;
using one or more electronic processors, transforming the data representing video by encoding a signal therein, in which the encoding introduces changes to the data representing video over time so as to reduce perceptible changes introduced by the encoding, and in which the encoding comprises first watermarking and second watermarking, which are encoded in corresponding spatial positions of the video,
in which said transforming yields encoded data, in which the first watermarking utilizes a first embedding bump size, and the second watermarking utilizes a second embedding bump size, in which the first embedding bump size corresponds with a first detection range distance when capturing optical scan data of encoded data, and the second embedding bump size corresponds with a second, larger detection range distance when capturing optical scan data of the encoded data
and in which portions within the data representing video which host the encoding change over time; and
providing the encoded data.
2. The method of claim 1 in which use of both the first embedding bump size and the second embedding bump size extends the detection range distance when capturing optical scan data associated with the encoded data.
3. The method of claim 2 in which the optical scan data comprises video data captured from a rendering of the encoded data.
4. The method of claim 1 further comprising preconditioning the signal prior to encoding.
5. The method of claim 1 in which the portions change in terms of pixel area or size.
6. The method of claim 5 in which the portions comprises bumps.
7. The method of claim 6 in which the bumps comprise encoding areas.
8. The method of claim 1 in which the encoding reduces perceptible changes introduced by the encoding by inversing polarity of related adjustments to the data representing video.
9. An apparatus comprising:
an input to receive data representing video;
memory storing instructions;
one or more electronic processors configured with said instructions to perform the following:
altering the data representing video by encoding a signal therein, in which the encoding introduces changes to the data representing video over time so as to reduce perceptible changes introduced by the encoding, in which the encoding reduces perceptible changes introduced by the encoding by inversing polarity of related adjustments to the data representing video, and
in which the altering yields encoded data,
and in which portions within the data representing video which host the encoding change over time; and
providing the encoded data.
10. The apparatus of claim 9 in which the encoding comprises first watermarking and second watermarking, which are encoded in corresponding spatial positions of the video, and in which the first watermarking utilizes a first embedding bump size, and the second watermarking utilizes a second embedding bump size, in which the first embedding bump size corresponds with a first detection range distance when capturing optical scan data of a rendering of the encoded data, and the second embedding bump size corresponds with a second, larger detection range distance when capturing optical scan data of a rendering of the encoded data.
11. The apparatus of claim 10 in which use of both the first embedding bump size and the second embedding bump size extends the detection range distance when capturing optical scan data associated with the encoded data.
12. The apparatus of claim 11 in which the optical scan data comprises video data captured from a rendering of the encoded data.
13. The apparatus of claim 9 in which the one or more electronic processors are configured with said instructions to perform preconditioning the signal prior to encoding.
14. The apparatus of claim 9 in which the portions change in terms of pixel area or size.
15. The apparatus of claim 14 in which the portions comprises bumps.
16. The apparatus of claim 15 in which the bumps comprise encoding areas.