In a previous post I discussed in-store marketing. One convenient way to do in-store marketing is to use use printed media to initiate an online interaction. In this post I will look at the patent situation for this class of applications.
There are several possible approaches:
- Put some readable marks on the page, but don't specify how.
- Use a barcode.
- Embed a hidden pattern in the printed image. This is sometime called Steganography or watermarking.
- Write the marks in an invisible ink or toner.
- Work with printer and scanner vendors to make their print and scan processes not corrupt the marks.
- Create marks that work with a large fraction of the printers and scanners that are likely to be used for this process. Mobile phone cameras may present a special challenge.
- System and method for automatic access of a remote computer over a network "A system and method for using identification codes to access particular computers on a network, including the use of bar codes to lookup information about products via a network." ran afoul of the EFF for crimes against the public domain EFF's patent description is much easier to read than the original patent.
- Automatic access of electronic information through secure machine-readable codes on printed documents (1999)
The system utilizes a machine-readable code printed on a document, referred to herein as an intelligent document since it stores information used to automatically access the information. The machine-readable symbol is encoded with source data (including a file location pointer) that is first obfuscated by generating a checksum of the source data, encrypting the source data by using the checksum as an encryption key, and assembling the checksum with the encrypted source data prior to encoding. The machine-readable symbol is then printed and distributed by the vendor by any logical means to the end user. The end user then scans the code via appropriate code scanning (e.g. bar code scanning) equipment, and de-obfuscates the scanned data by parsing the checksum, decrypting the remainder of the scanned data string (which includes the file location pointer) using the parsed checksum as a decryption key, computing a checksum of the decrypted data string, and comparing the computed checksum with the parsed checksum to determine the validity of the code. The file location pointer is then used to access the appropriate file. In a preferred embodiment, a Web browser program is launched, and the URL of the vendor's Web site is accessed through the Internet.
HyperLabel uses a pattern drawn in invisible ink and may require special printers and scanners.
A method and apparatus of profile guided printing of a paper document facilitates back channel interaction from a reader for contemporaneous upgrading of the profile in response to document content. The document is printed to include tokens representative of the reader and its content. While being read, the document is redacted by the subscriber in a predetermined manner representing desired changes in the document, or responses to publisher inquiries. The document can be scanned in a smart recycling bin to identify the reader and the desired changes. The reader profile is adjusted by the publisher into an upgraded reader profile upon identification of the reader redactions. Alternatively, a smart wand is used to detect the document and contents and is controlled by the user to indicate changes to the contents. The wand can store the user's and document's identification, and the desired changes and can be downloaded for updating the profile. The next document generated corresponds to the upgraded profile.Microsoft (High Capacity Color Barcode)
- Mark embedding and detection using projective transforms
Certain marks have near perfect correlation properties, allowing virtually all the energy of the mark to be concentrated into a single detection point. Unfortunately most correlation processes are effectively destroyed, or at least severelyimpeded, by distortions of the marked signal. In two dimensions, common distortions include rotation, scaling, anamorphic scaling and shear.
- Method for the enhancement of complex peaks
For example, watermarking often relies on the imperceptible embedding of a known pattern in a signal, with the signal being a single-dimensional signal, or multi-dimensional signal such as an image, video or 3D space. The detection of the presence of the known embedded pattern is then facilitated by a matched filtering operation, which is commonly called correlation. The result of correlation of suitable patterns is a sharp peak at the position of best overlap between the known patternand the signal with the embedded pattern. However, it is often desirable to make the intensity of the embedded pattern as small as reasonably possible, thereby allowing the embedded pattern to be imperceptible by a human. For example, it is desirablefor the embedded pattern to be imperceptible to the human eye in the case of an image watermarking, or human ear in the case of audio watermarking.
It is an object of the present invention to substantially overcome, or at least ameliorate, one or more disadvantages of existing arrangements.According to a first aspect of the invention, there is provided a method of pre-processing data including a watermark before detecting said watermark by correlating said data with said watermark, said method comprising the steps of:
(a) dividing said data into a plurality of sub-spaces, each sub-space being associated with a position within said data;
(b) for each sub-space, spectral shaping frequency amplitudes of the data of said sub-space to a predetermined function; and
(c) adding said data of said sub-spaces at positions corresponding with said sub-space positions.
A digital watermark may be applied to digital image data to produce watermarked digital image data. A transformation may be applied to the watermarked digital image data to produce transformed watermarked digital image data. The transformation may approximate the inverse of a transformation that represents distortion caused by transmission through a print-scan channel.