Method and apparatus for using a limited capacity portable data carrier

• US 20080245868A1
• Filed: 03/24/2008
• Published: 10/09/2008
• Est. Priority Date: 03/23/2007
• Status: Active Grant

• Current Assignee: LTT Limited
• Original Assignee: LTT Limited
• Inventors: Berkun, Kenneth A.
• Granted Patent: US 8,226,007 B2
• Time in Patent Office: Days
• US Class Current: 235/462.1
• CPC Class Codes: G06K 1/12 otherwise than by punching
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1491 the method including a reconstruction step, e.g. stitching two pieces of bar code together to derive the full bar code

Abstract

A method for reading and using partial data from a portable data carrier includes reading data from a portable data carrier, determining if any data is missing, and if any data is missing, restructuring the data for use, such as for running an audio decoder and expander. A method for writing data to a portable data carrier having limited capacity includes receiving a data file and optimizing at least one encoding parameter to fit at least a portion of the data file into the portable data carrier.

Claims

1. A method for reading and using partial data from a bar code comprising:

interrogating a 2D bar code symbol that includes a plurality of data segments;

determining if at least one segment of data is missing from the received data; and

if at least one segment of data is missing, restructuring the data to run through a decoder and expander.

2. The method of claim 1 wherein the 2D bar code symbol is a 2D matrix bar code symbol that includes explicitly encoded data segments with segment identification fields.

3. The method of claim 1 wherein the 2D bar code symbol is a 2D matrix bar code symbol that includes data segments without explicit segment identification fields.

4. The method of claim 1 wherein determining if at least one segment of data is missing from the received data includes at least one selected from the group consisting of:

analyzing the data to determine if the returned data is continuous;

identifying segments of data returned from the symbol and determining if any gaps exist between segments, analyzing the signal to determine if a substantially constant frequency component is phase shifted between received data segments; and

determining if an improbable signal transient is encoded between the received data segments.

5. The method of claim 1 wherein the decoder and expander includes an audio codec.

6. The method of claim 1 wherein structuring the data to run through a decoder and expander includes separating segments in the received data.

7. The method of claim 1 wherein structuring the data to run through a decoder and expander includes inserting pad characters between the received data segments.

8. The method of claim 1 wherein restructuring the data to run through a decoder and expander includes generating pad characters between the received data segments to put the received data segments in proper temporal registration, wherein the pad characters are generated using at least one selected from the group consisting of:

generating blank data characters as pad characters, generating pad characters corresponding to white noise, generating pad characters corresponding to pink noise, generating pad characters that are amplitude matched to neighboring received data, generating pad characters that are frequency matched with neighboring received data, generating pad characters that include a morph between the spaced-apart returned data segments, generating pad characters that include a duplication of at least one of the neighboring returned data segments, and generating pad characters from a best match between another portion of returned data and the neighboring portions of the returned data.

9. The method of claim 1 further comprising playing restructured data through a codec.

10. The method of claim 1 wherein returned data is decoded by a codec prior to restructuring the received data.

11. A method for writing data to a bar code symbol having limited capacity comprising:

receiving a data file corresponding to a human perceivable signal;

reducing the size of the data file; and

bitmapping a 2D bar code symbol to include the reduced size data file.

12. The method of claim 11 further comprising:

determining an amount of data to be removed from the received data file to fit in a bar code symbol; and

wherein

the size of the data file is reduced by the determined amount of data to be removed.

13. The method of claim 11 wherein the size of the data file is reduced by at least one selected from the group consisting of:

cropping the data file, decreasing a sampling rate, removing least significant bits, reducing a frequency range, decreasing harmonic content, converting to a higher compression file format, omitting data segments, reducing dynamic range, and reducing error correction.

14. The method of claim 11 further comprising:

transducing an audio signal to a corresponding electrical signal; and

converting the electrical signal to the data file.

15. A method for writing data to a bar code symbol having limited capacity comprising:

receiving a data file; and

optimizing at least one encoding parameter to fit at least a portion of the data file into a bar code symbol.

16. The method of claim 15 further comprising:

generating a 2D matrix bar code bitmap using the at least one optimized encoding parameter.

17. The method of claim 15 further comprising:

printing a 2D matrix bar code using the at least one optimized encoding parameter.

18. The method of claim 15 wherein optimizing at least one encoding parameter includes selecting at least one selected from the group consisting of:

data file error correction, eliminated data file error correction, reduced data file error correction, symbol error correction, reduced symbol error correction, eliminated symbol error correction, and data reduction from the data file.

19. The method of claim 15 wherein optimizing at least one encoding parameter includes selecting the at least one encoding parameter to fit a fixed symbol size.

20. The method of claim 15 wherein optimizing the at least one encoding parameter includes selecting a plurality of encoding parameters that balance the probability of symbol reading against the quality of an audio file encoded in the data.

21. The method of claim 15 wherein optimizing at least one encoding parameter includes selecting a size of a plurality of data segments.

22. The method of claim 15 wherein the data file includes an audio file.

23. A system configured to read and use a partial set of data from a 2D bar code symbol comprising:

an image capture module configured to capture at an image corresponding to at least a portion of a 2D matrix symbol;

a processor configured to determine if at least one segment of data is missing in audio data read from the 2D matrix symbol, and if at least one segment of data is missing, restructure the data for optimum playback.

24. The system of claim 23 wherein determining if at least one segment of data is missing in the audio data includes at least one selected from the group consisting of:

analyzing the data to determine if the returned data is continuous;

identifying segments of data returned from the symbol and determining if any gaps exist between segments, analyzing the signal to determine if a substantially constant frequency component is phase shifted between received data segments; and

determining if an improbable signal transient is encoded between the received data segments.

25. The system of claim 23 wherein restructuring the data for optimum playback includes putting the received data segments in proper temporal registration,

26. The system of claim 23 wherein restructuring the data for optimum playback includes generating pad characters between the received data segments to put the received data segments in proper temporal registration, wherein the pad characters are generated using at least one selected from the group consisting of:

generating blank data characters as pad characters, generating pad characters corresponding to white noise, generating pad characters corresponding to pink noise, generating pad characters that are amplitude matched to neighboring received data, generating pad characters that are frequency matched with neighboring received data, generating pad characters that include a morph between the spaced-apart returned data segments, generating pad characters that include a duplication of at least one of the neighboring returned data segments, and generating pad characters from a best match between another portion of returned data and the neighboring portions of the returned data.

27. The system of claim 23, further comprising an output module configured to receive a signal corresponding to the restructured audio data and output the audio data.

28. A system configured to output a bar code symbol carrying audio data comprising:

a memory configured to receive an audio data file; and

a processor configured to optimize at least one encoding parameter to fit at least a portion of the audio data file into a bar code symbol.

29. The system of claim 28 further comprising:

an audio codec configured to receive an audio signal and output the audio data file to the memory.

30. The system of claim 28 wherein optimizing at least one encoding parameter includes selecting at least one selected from the group consisting of:

data file error correction, eliminated data file error correction, reduced data file error correction, symbol error correction, reduced symbol error correction, eliminated symbol error correction, data reduction from the data file, and a size of a plurality of data segments.

31. The system of claim 28 wherein optimizing at least one encoding parameter includes selecting the at least one encoding parameter to fit a fixed symbol size.

32. The system of claim 28 wherein optimizing the at least one encoding parameter includes selecting a plurality of encoding parameters that balance the probability of symbol reading against the quality of an audio file encoded in the symbol.

33. A method for writing data to a portable data carrier comprising:

receiving data containing payload error correction;

removing the payload error correction; and

writing the remaining data to a portable data carrier.

34. A method for writing data to a portable data carrier comprising:

receiving data;

determining the data contains payload error correction; and

writing the data to a portable data carrier without adding additional error correction.

35. A method for processing data from a portable data carrier comprising:

interrogating the portable data carrier;

receiving a portion less than the full amount of the data in the portable data carrier; and

processing the portion of data.

36. The method of claim 35 wherein processing the portion of data includes playing back the data through an audio codec.

35-1. (canceled)